Do not overwrite fresh backups

If the backup file is less than an hour old, do not overwrite it.

Makefile

@@ -31,7 +31,7 @@ test:
 upload:
 	go build
 	rsync --itemize-changes --archive oddmu sibirocobombus.root:/home/oddmu/
-	ssh sibirocobombus.root "systemctl restart oddmu; systemctl restart alex"
+	ssh sibirocobombus.root "systemctl restart oddmu; systemctl restart alex; systemctl restart claudia"
 	@echo Changes to the template files need careful consideration
 
 docs:

README.md

@@ -10,21 +10,75 @@ as a *secondary* medium: collaboration and conversation happens
 elsewhere, in chat, on social media. The wiki serves as the text
 repository that results from these discussions.
 
-The wiki lists no recent changes. The expectation is that the people
-that care were involved in the discussions beforehand.
+If you're the only user and it just runs on your laptop, then you can
+think of it as a [memex](https://en.wikipedia.org/wiki/Memex), a
+memory extender.
 
 This wiki uses a [Markdown
 library](https://github.com/gomarkdown/markdown) to generate the web
 pages from Markdown. There are two extensions Oddmu adds to the
-library: local links `[[like this]]` and hashtags `#Like_This`.
+library: local links `[[like this]]`, hashtags `#Like_This` and
+fediverse account links like @alex@alexschroeder.ch.
 
-This wiki uses the [lingua](github.com/pemistahl/lingua-go) library to
-detect languages in order to get hyphenation right.
+This wiki uses the [lingua](https://github.com/pemistahl/lingua-go)
+library to detect languages in order to get hyphenation right.
 
 This wiki uses the standard
 [html/template](https://pkg.go.dev/html/template) library to generate
 HTML.
 
+## Documentation
+
+This project uses man(1) pages. They are generated from text files
+using [scdoc](https://git.sr.ht/~sircmpwn/scdoc). These are the files
+available:
+
+[oddmu(1)](/oddmu.git/blob/main/man/oddmu.1.txt): This man page has a
+short introduction to Oddmu, its configuration via templates and
+environment variables, plus points to the other man pages.
+
+[oddmu(5)](/oddmu.git/blob/main/man/oddmu.5.txt): This man page talks
+about the Markdown and includes some examples for the non-standard
+features such as table markup. It also talks about the Oddmu
+extensions to Markdown: wiki links, hashtags and fediverse account
+links. Local links must use percent encoding for page names so there
+is a section about percent encoding. The man page also explains how
+feeds are generated.
+
+[oddmu-search(1)](/oddmu.git/blob/main/man/oddmu-search.1.txt): This
+man page documents the "search" subcommand which you can use to build
+indexes – lists of page links. These are important for feeds.
+
+[oddmu-replace(1)](/oddmu.git/blob/main/man/oddmu-replace.1.txt): This
+man page documents the "replace" subcommand to make mass changes to
+the files much like find(1), grep(1) and sed(1) or perl (1).
+
+[oddmu-missing(1)](/oddmu.git/blob/main/man/oddmu-missing.1.txt): This
+man page documents the "missing" subcommand to list local links that
+don't point to any existing pages or files.
+
+[oddmu-html(1)](/oddmu.git/blob/main/man/oddmu-html.1.txt): This man
+page documents the "html" subcommand to generate HTML from Markdown
+pages from the command line.
+
+[oddmu-static(1)](/oddmu.git/blob/main/man/oddmu-static.1.txt): This
+man page documents the "static" subcommand to generate an entire
+static website from the command line, avoiding the need to run Oddmu
+as a server. Also great for archiving.
+
+[oddmu-templates(5)](/oddmu.git/blob/main/man/oddmu-templates.5.txt):
+This man page documents how the templates can be changed (how they
+*must* be changed) and lists the attributes available for the various
+templates.
+
+[oddmu-apache(5)](/oddmu.git/blob/main/man/oddmu-apache.5.txt): This
+man page documents how to set up the web server for various common
+tasks such as using logins to limit what visitors can edit.
+
+[oddmu.service(5)](/oddmu.git/blob/main/man/oddmu.service.5.txt): This
+man page documents how to setup a systemd unit and have it manage
+Oddmu. “Great configurability brings brings great burdens.”
+
 ## Building
 
 ```sh
@@ -48,6 +102,35 @@ your browser to http://localhost:8080/ to use it.
 
 If you spot any, [contact](https://alexschroeder.ch/wiki/Contact) me.
 
+## Source
+
+If you're interested in making changes to the code, here's a
+high-level introduction to the various source files.
+
+- *_test.go are the test files; a few library functions are defined in
+  wiki_test.go.
+- *_cmd.go are the files implementing the various subcommands with
+  matching names
+- accounts.go implements the webfinger code to fetch fediverse account
+  link destinations with the URI provided by webfinger
+- add_append.go implements the /add and /append handlers
+- diff.go implements the /diff handler
+- edit_save.go implements the /edit and /save handlers
+- feed.go implements the feed for a page based on the links it lists
+- highlight.go implements the bold tags for matches when showing
+  search results
+- index.go implements the index of all the hashtags
+- languages.go implements the language detection
+- page.go implements the page loading and saving
+- parser.go implements the Markdown parsing
+- score.go implements the page scoring when showing search results
+- search.go implements the /search handler
+- snippets.go implements the page summaries for search results
+- tokenizer.go implements the various tokenizers used
+- upload_drop.go implements the /upload and /drop handlers
+- view.go implements the /view handler
+- wiki.go implements the main function
+
 ## References
 
 [Writing Web Applications](https://golang.org/doc/articles/wiki/)

accounts.go

@@ -2,10 +2,10 @@ package main
 
 import (
 	"encoding/json"
-	"fmt"
 	"github.com/gomarkdown/markdown/ast"
 	"github.com/gomarkdown/markdown/parser"
 	"io"
+	"log"
 	"net/http"
 	"os"
 	"sync"
@@ -57,6 +57,7 @@ func account(p *parser.Parser, data []byte, offset int) (int, ast.Node) {
 		data[i] >= '0' && data[i] <= '9' ||
 		data[i] == '@' ||
 		data[i] == '.' ||
+		data[i] == '_' ||
 		data[i] == '-') {
 		if data[i] == '@' {
 			if d != 0 {
@@ -82,14 +83,15 @@ func account(p *parser.Parser, data []byte, offset int) (int, ast.Node) {
 	uri, ok := accounts.uris[string(account)]
 	defer accounts.RUnlock()
 	if !ok {
-		fmt.Printf("Looking up %s\n", account)
+		log.Printf("Looking up %s\n", account)
 		uri = "https://" + string(domain) + "/users/" + string(user[1:])
 		accounts.uris[string(account)] = uri // prevent more lookings
 		go lookUpAccountUri(string(account), string(domain))
 	}
 	link := &ast.Link{
-		Destination: []byte(uri),
-		Title:       data[0:i],
+		AdditionalAttributes: []string{`class="account"`},
+		Destination:          []byte(uri),
+		Title:                data[0:i],
 	}
 	ast.AppendChild(link, &ast.Text{Leaf: ast.Leaf{Literal: data[0 : d-1]}})
 	return i, link
@@ -103,26 +105,26 @@ func lookUpAccountUri(account, domain string) {
 	uri := "https://" + domain + "/.well-known/webfinger"
 	resp, err := http.Get(uri + "?resource=acct:" + account)
 	if err != nil {
-		fmt.Printf("Failed to look up %s: %s\n", account, err)
+		log.Printf("Failed to look up %s: %s", account, err)
 		return
 	}
 	defer resp.Body.Close()
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {
-		fmt.Printf("Failed to read from %s: %s\n", account, err)
+		log.Printf("Failed to read from %s: %s", account, err)
 		return
 	}
 	var wf WebFinger
 	err = json.Unmarshal([]byte(body), &wf)
 	if err != nil {
-		fmt.Printf("Failed to parse the JSON from %s: %s\n", account, err)
+		log.Printf("Failed to parse the JSON from %s: %s", account, err)
 		return
 	}
 	uri, err = parseWebFinger(body)
 	if err != nil {
-		fmt.Printf("Could not find profile URI for %s: %s\n", account, err)
+		log.Printf("Could not find profile URI for %s: %s", account, err)
 	}
-	fmt.Printf("Found profile for %s: %s\n", account, uri)
+	log.Printf("Found profile for %s: %s", account, uri)
 	accounts.Lock()
 	defer accounts.Unlock()
 	accounts.uris[account] = uri

accounts_test.go

@@ -10,7 +10,7 @@ import (
 // 	initAccounts()
 // 	p := &Page{Body: []byte(`@alex, @alex@alexschroeder.ch said`)}
 // 	p.renderHtml()
-// 	r := `<p>@alex, <a href="https://alexschroeder.ch/users/alex" rel="nofollow">@alex</a> said</p>
+// 	r := `<p>@alex, <a href="https://alexschroeder.ch/users/alex">@alex</a> said</p>
 // `
 // 	assert.Equal(t, r, string(p.Html))
 // }

add.html

@@ -6,7 +6,7 @@
     <meta name="viewport" content="width=device-width">
     <title>Add to {{.Title}}</title>
     <style>
-html { max-width: 70ch; padding: 2ch; margin: auto; color: #111; background: #ffe; }
+html { max-width: 70ch; padding: 2ch; margin: auto; color: #111; background-color: #ffe; }
 form, textarea { width: 100%; }
     </style>
   </head>
@@ -14,6 +14,7 @@ form, textarea { width: 100%; }
     <h1>Adding to {{.Title}}</h1>
     <form action="/append/{{.Name}}" method="POST">
       <textarea name="body" rows="20" cols="80" placeholder="Text" lang="" autofocus required></textarea>
+      <p><label><input type="checkbox" name="notify" checked> Add link to <a href="/view/changes">the list of changes</a>.</label></p>
       <p><input type="submit" value="Add">
         <a href="/view/{{.Name}}"><button type="button">Cancel</button></a></p>
     </form>

add_append.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"bytes"
+	"log"
 	"net/http"
 )
 
@@ -23,15 +25,32 @@ func appendHandler(w http.ResponseWriter, r *http.Request, name string) {
 	body := r.FormValue("body")
 	p, err := loadPage(name)
 	if err != nil {
-		p = &Page{Title: name, Name: name, Body: []byte(body)}
+		p = &Page{Name: name, Body: []byte(body)}
 	} else {
-		p.handleTitle(false)
-		p.Body = append(p.Body, []byte(body)...)
+		p.append([]byte(body))
 	}
+	p.handleTitle(false)
 	err = p.save()
 	if err != nil {
 		http.Error(w, err.Error(), http.StatusInternalServerError)
 		return
 	}
+	if r.FormValue("notify") == "on" {
+		err = p.notify()
+		if err != nil {
+			log.Println("notify:", err)
+		}
+	}
 	http.Redirect(w, r, "/view/"+name, http.StatusFound)
 }
+
+func (p *Page) append(body []byte) {
+	// ensure an empty line at the end
+	if bytes.HasSuffix(p.Body, []byte("\n\n")) {
+	} else if bytes.HasSuffix(p.Body, []byte("\n")) {
+		p.Body = append(p.Body, '\n')
+	} else {
+		p.Body = append(p.Body, '\n', '\n')
+	}
+	p.Body = append(p.Body, body...)
+}

add_append_test.go

@@ -6,14 +6,26 @@ import (
 	"os"
 	"regexp"
 	"testing"
+	"time"
 )
 
-// wipes testdata
+func TestEmptyLineAdd(t *testing.T) {
+	p := &Page{Name: "testdata/add/fire", Body: []byte(`# Coal
+Black rocks light as foam
+Shaking, puring, shoveling`)}
+	p.append([]byte("Into the oven"))
+	assert.Equal(t, string(p.Body), `# Coal
+Black rocks light as foam
+Shaking, puring, shoveling
+
+Into the oven`)
+}
+
 func TestAddAppend(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/add")
 	index.load()
 
-	p := &Page{Name: "testdata/fire", Body: []byte(`# Fire
+	p := &Page{Name: "testdata/add/fire", Body: []byte(`# Fire
 Orange sky above
 Reflects a distant fire
 It's not `)}
@@ -23,14 +35,43 @@ It's not `)}
 	data.Set("body", "barbecue")
 
 	assert.Regexp(t, regexp.MustCompile("a distant fire"),
-		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/fire", nil))
+		assert.HTTPBody(makeHandler(viewHandler, true),
+			"GET", "/view/testdata/add/fire", nil))
 	assert.NotRegexp(t, regexp.MustCompile("a distant fire"),
-		assert.HTTPBody(makeHandler(addHandler, true), "GET", "/add/testdata/fire", nil))
-	HTTPRedirectTo(t, makeHandler(appendHandler, true), "POST", "/append/testdata/fire", data, "/view/testdata/fire")
-	assert.Regexp(t, regexp.MustCompile("It’s not barbecue"),
-		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/fire", nil))
-
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+		assert.HTTPBody(makeHandler(addHandler, true),
+			"GET", "/add/testdata/add/fire", nil))
+	HTTPRedirectTo(t, makeHandler(appendHandler, true),
+		"POST", "/append/testdata/add/fire", data, "/view/testdata/add/fire")
+	assert.Regexp(t, regexp.MustCompile(`not</p>\s*<p>barbecue`),
+		assert.HTTPBody(makeHandler(viewHandler, true),
+			"GET", "/view/testdata/add/fire", nil))
+}
+
+func TestAddAppendChanges(t *testing.T) {
+	cleanup(t, "testdata/notification2", "changes.md", "changes.md~")
+	restore(t, "index.md")
+	os.Remove("changes.md")
+	today := time.Now().Format(time.DateOnly)
+
+	p := &Page{Name: "testdata/notification2/" + today + "-water", Body: []byte(`# Water
+Sunlight dancing fast
+Blue and green and pebbles gray
+`)}
+	p.save()
+
+	data := url.Values{}
+	data.Set("body", "Stand in cold water")
+	data.Add("notify", "on")
+	HTTPRedirectTo(t, makeHandler(appendHandler, true),
+		"POST", "/append/testdata/notification2/"+today+"-water",
+		data, "/view/testdata/notification2/"+today+"-water")
+	// The changes.md file was created
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	d := time.Now().Format(time.DateOnly)
+	assert.Equal(t, "# Changes\n\n## "+d+"\n* [Water](testdata/notification2/"+today+"-water)\n", string(s))
+	// Link added to index.md file
+	s, err = os.ReadFile("index.md")
+	assert.NoError(t, err)
+	assert.Contains(t, string(s), "\n* [Water](testdata/notification2/"+today+"-water)\n")
 }

changes.go

@@ -0,0 +1,176 @@
+package main
+
+import (
+	"path"
+	"regexp"
+	"strings"
+	"time"
+)
+
+// notify adds a link to the "changes" page, as well as to all the existing hashtag pages. If the "changes" page does
+// not exist, it is created. If the hashtag page does not exist, it is not. Hashtag pages are considered optional.
+func (p *Page) notify() error {
+	p.handleTitle(false)
+	if p.Title == "" {
+		p.Title = p.Name
+	}
+	esc := nameEscape(p.Name)
+	link := "* [" + p.Title + "](" + esc + ")\n"
+	re := regexp.MustCompile(`(?m)^\* \[[^\]]+\]\(` + esc + `\)\n`)
+	dir := path.Dir(p.Name)
+	// Recent changes for all pages
+	err := addLinkWithDate("changes", link, re)
+	if err != nil {
+		return err
+	}
+	// For blog pages only…
+	if p.isBlog() {
+		// Add to the index only if the blog post is for the current year
+		if strings.HasPrefix(path.Base(p.Name), time.Now().Format("2006")) {
+			err := addLink("index", link, re)
+			if err != nil {
+				return err
+			}
+		}
+		// Update hashtag pages
+		p.renderHtml() // to set hashtags
+		for _, hashtag := range p.Hashtags {
+			err := addLink(path.Join(dir, hashtag), link, re)
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// addLinkWithDate adds the link to a page, with date header for today. If a match already exists, it is removed. If
+// this leaves a date header without any links, it is removed as well. If a list is found, the link is added at the top
+// of the list. Lists must use the asterisk, not the minus character.
+func addLinkWithDate(name, link string, re *regexp.Regexp) error {
+	date := time.Now().Format(time.DateOnly)
+	org := ""
+	c, err := loadPage(name)
+	if err != nil {
+		// create a new page
+		c = &Page{Name: "changes", Body: []byte("# Changes\n\n## " + date + "\n" + link)}
+	} else {
+		org = string(c.Body)
+		// remove the old match, if one exists
+		loc := re.FindIndex(c.Body)
+		if loc != nil {
+			r := c.Body[:loc[0]]
+			if loc[1] < len(c.Body) {
+				r = append(r, c.Body[loc[1]:]...)
+			}
+			c.Body = r
+			if loc[0] >= 14 && len(c.Body) >= loc[0]+15 {
+				// remove the preceding date if there are now two dates following each other
+				re := regexp.MustCompile(`(?m)^## (\d\d\d\d-\d\d-\d\d)\n\n## (\d\d\d\d-\d\d-\d\d)\n`)
+				if re.Match(c.Body[loc[0]-14 : loc[0]+15]) {
+					c.Body = append(c.Body[0:loc[0]-14], c.Body[loc[0]+1:]...)
+				}
+			} else if len(c.Body) == loc[0] {
+				// remove a trailing date
+				re := regexp.MustCompile(`## (\d\d\d\d-\d\d-\d\d)\n`)
+				if re.Match(c.Body[loc[0]-14 : loc[0]]) {
+					c.Body = c.Body[0 : loc[0]-14]
+				}
+			}
+		}
+		// locate the beginning of the list to insert the line
+		re := regexp.MustCompile(`(?m)^\* \[[^\]]+\]\([^\)]+\)\n`)
+		loc = re.FindIndex(c.Body)
+		if loc == nil {
+			// if no list was found, use the end of the page
+			loc = []int{len(c.Body)}
+		}
+		// start with new page content
+		r := []byte("")
+		// check if there is a date right before the insertion point
+		addDate := true
+		if loc[0] >= 14 {
+			re := regexp.MustCompile(`(?m)^## (\d\d\d\d-\d\d-\d\d)\n`)
+			m := re.Find(c.Body[loc[0]-14 : loc[0]])
+			if m == nil {
+				// not a date: insert date, don't move insertion point
+			} else if string(c.Body[loc[0]-11:loc[0]-1]) == date {
+				// if the date is our date, don't add it, don't move insertion point
+				addDate = false
+			} else {
+				// if the date is not out date, move the insertion point
+				loc[0] -= 14
+			}
+		}
+		// append up to the insertion point
+		r = append(r, c.Body[:loc[0]]...)
+		// append date, if necessary
+		if addDate {
+			// ensure paragraph break
+			if len(r) > 0 && r[len(r)-1] != '\n' {
+				r = append(r, '\n')
+			}
+			if len(r) > 1 && r[len(r)-2] != '\n' {
+				r = append(r, '\n')
+			}
+			r = append(r, []byte("## ")...)
+			r = append(r, []byte(date)...)
+			r = append(r, '\n')
+		}
+		// append link
+		r = append(r, []byte(link)...)
+		// if we just added a date, add an empty line after the single-element list
+		if len(c.Body) > loc[0] && c.Body[loc[0]] != '*' {
+			r = append(r, '\n')
+		}
+		// append the rest
+		r = append(r, c.Body[loc[0]:]...)
+		c.Body = r
+	}
+	// only save if something changed
+	if string(c.Body) != org {
+		return c.save()
+	}
+	return nil
+}
+
+// addLink adds a link to a named page, if the page exists and doesn't contain the link. If the link exists but with a
+// different title, the title is fixed.
+func addLink(name, link string, re *regexp.Regexp) error {
+	c, err := loadPage(name)
+	if err != nil {
+		// Skip non-existing files: no error
+		return nil
+	}
+	org := string(c.Body)
+	// if a link exists, that's the place to insert the new link (in which case loc[0] and loc[1] differ)
+	loc := re.FindIndex(c.Body)
+	// if no link exists, find a good place to insert it
+	if loc == nil {
+		// locate the beginning of the list to insert the line
+		re = regexp.MustCompile(`(?m)^\* \[[^\]]+\]\([^\)]+\)\n`)
+		loc = re.FindIndex(c.Body)
+		if loc == nil {
+			// if no list was found, use the end of the page
+			m := len(c.Body)
+			loc = []int{m, m}
+		} else {
+			// if a list item was found, use just the beginning as insertion point
+			loc[1] = loc[0]
+		}
+	}
+	// start with new page content
+	r := []byte("")
+	// append up to the insertion point
+	r = append(r, c.Body[:loc[0]]...)
+	// append link
+	r = append(r, []byte(link)...)
+	// append the rest
+	r = append(r, c.Body[loc[1]:]...)
+	c.Body = r
+	// only save if something changed
+	if string(c.Body) != org {
+		return c.save()
+	}
+	return nil
+}

changes_test.go

@@ -0,0 +1,199 @@
+package main
+
+import (
+	"github.com/stretchr/testify/assert"
+	"os"
+	"testing"
+	"time"
+)
+
+// Note TestEditSaveChanges and TestAddAppendChanges.
+
+func TestChanges(t *testing.T) {
+	cleanup(t, "changes.md", "changes.md~")
+	restore(t, "index.md")
+	os.Remove("changes.md")
+	today := time.Now().Format(time.DateOnly)
+	p := &Page{Name: "testdata/" + today + "-machine",
+		Body: []byte(`# Washing machine
+Churning growling thing
+Water spraying in a box 
+Out of sight and dark`)}
+	p.notify()
+	// Link added to changes.md file
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	assert.Contains(t, string(s), "[Washing machine](testdata/"+today+"-machine)")
+	// Link added to index.md file
+	s, err = os.ReadFile("index.md")
+	assert.NoError(t, err)
+	assert.Contains(t, string(s), "\n* [Washing machine](testdata/"+today+"-machine)\n")
+}
+
+func TestChangesWithHashtag(t *testing.T) {
+	cleanup(t, "changes.md", "changes.md~")
+	restore(t, "index.md")
+	os.Remove("changes.md")
+	intro := "# Haiku\n"
+	line := "* [Hotel room](testdata/changes/2023-10-27-hotel)\n"
+	h := &Page{Name: "testdata/changes/Haiku", Body: []byte(intro)}
+	h.save()
+	p := &Page{Name: "testdata/changes/2023-10-27-hotel",
+		Body: []byte(`# Hotel room
+White linen and white light
+Wooden floor and painted walls
+Home away from home
+
+#Haiku #Poetry`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	assert.Contains(t, string(s), line)
+	s, err = os.ReadFile("testdata/changes/Haiku.md")
+	assert.NoError(t, err)
+	assert.Equal(t, intro+line, string(s))
+	assert.NoFileExists(t, "testdata/changes/Poetry.md")
+}
+
+func TestChangesWithList(t *testing.T) {
+	cleanup(t, "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph.\n\n"
+	line := "* [a change](change)\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.WriteFile("changes.md", []byte(intro+d+line), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// new line was added at the beginning of the list
+	assert.Equal(t, intro+d+new_line+line, string(s))
+}
+
+func TestChangesWithOldList(t *testing.T) {
+	cleanup(t, "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph.\n\n"
+	line := "* [a change](change)\n"
+	y := "## " + time.Now().Add(-24*time.Hour).Format(time.DateOnly) + "\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.WriteFile("changes.md", []byte(intro+y+line), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// new line was added at the beginning of the list
+	assert.Equal(t, intro+d+new_line+"\n"+y+line, string(s))
+}
+
+func TestChangesWithOldDisappearingListAtTheEnd(t *testing.T) {
+	cleanup(t, "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph.\n\n"
+	line := "* [a change](testdata/changes/alex)\n"
+	y := "## " + time.Now().Add(-24*time.Hour).Format(time.DateOnly) + "\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.WriteFile("changes.md", []byte(intro+y+line), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// new line was added at the beginning of the list, with the new date, and the old date disappeared
+	assert.Equal(t, intro+d+new_line, string(s))
+}
+
+func TestChangesWithOldDisappearingListInTheMiddle(t *testing.T) {
+	cleanup(t, "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph.\n\n"
+	line := "* [a change](testdata/changes/alex)\n"
+	other := "* [other change](testdata/changes/whatever)\n"
+	yy := "## " + time.Now().Add(-48*time.Hour).Format(time.DateOnly) + "\n"
+	y := "## " + time.Now().Add(-24*time.Hour).Format(time.DateOnly) + "\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.WriteFile("changes.md", []byte(intro+y+line+"\n"+yy+other), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// new line was added at the beginning of the list, with the new date, and the old date disappeared
+	assert.Equal(t, intro+d+new_line+"\n"+yy+other, string(s))
+}
+
+func TestChangesWithListAtTheTop(t *testing.T) {
+	cleanup(t, "testdata/changes", "changes.md", "changes.md~")
+	line := "* [a change](change)\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.WriteFile("changes.md", []byte(line), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// new line was added at the top, no error due to missing introduction
+	assert.Equal(t, d+new_line+line, string(s))
+}
+
+func TestChangesWithNoList(t *testing.T) {
+	cleanup(t, "testdata/changes", "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph."
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.WriteFile("changes.md", []byte(intro), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// into is still there and a new list was started
+	assert.Equal(t, intro+"\n\n"+d+new_line, string(s))
+}
+
+func TestChangesWithUpdate(t *testing.T) {
+	cleanup(t, "testdata/changes", "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph.\n\n"
+	other := "* [other change](testdata/changes/whatever)\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	line := "* [a change](testdata/changes/alex)\n"
+	os.WriteFile("changes.md", []byte(intro+d+other+line), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// the change was already listed, but now it moved up and has a new title
+	assert.Equal(t, intro+d+new_line+other, string(s))
+}
+
+func TestChangesWithNoChangeToTheOrder(t *testing.T) {
+	cleanup(t, "testdata/changes", "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph.\n\n"
+	other := "* [other change](testdata/changes/whatever)\n"
+	line := "* [a change](testdata/changes/alex)\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.WriteFile("changes.md", []byte(intro+d+line+other), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte(`Hallo!`)}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	new_line := "* [testdata/changes/alex](testdata/changes/alex)\n"
+	// the change was already listed at the top, so just use the new title
+	assert.Equal(t, intro+d+new_line+other, string(s))
+}
+
+func TestChangesWithNoChanges(t *testing.T) {
+	cleanup(t, "testdata/changes", "changes.md", "changes.md~")
+	intro := "# Changes\n\nThis is a paragraph.\n\n"
+	other := "* [other change](testdata/changes/whatever)\n"
+	line := "* [a change](testdata/changes/alex)\n"
+	d := "## " + time.Now().Format(time.DateOnly) + "\n"
+	os.Remove("changes.md~")
+	os.WriteFile("changes.md", []byte(intro+d+line+other), 0644)
+	p := &Page{Name: "testdata/changes/alex", Body: []byte("# a change\nHallo!")}
+	p.notify()
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	// the change was already listed at the top, so no change was necessary
+	assert.Equal(t, intro+d+line+other, string(s))
+	// since the file hasn't changed, no backup was necessary
+	assert.NoFileExists(t, "changes.md~")
+}

concurrency_test.go

@@ -10,6 +10,6 @@ func TestLoadAndSearch(t *testing.T) {
 	index.reset()
 	go index.load()
 	q := "Oddµ"
-	pages, _, _ := search(q, 1)
+	pages, _ := search(q, "", 1, false)
 	assert.Zero(t, len(pages))
 }

diff.go

@@ -0,0 +1,66 @@
+package main
+
+import (
+	"bytes"
+	"github.com/sergi/go-diff/diffmatchpatch"
+	"html"
+	"html/template"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+)
+
+func diffHandler(w http.ResponseWriter, r *http.Request, name string) {
+	p, err := loadPage(name)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	p.handleTitle(true)
+	p.renderHtml()
+	renderTemplate(w, "diff", p)
+}
+
+// Diff computes the diff for a page. At this point, renderHtml has already been called so the Name is escaped.
+func (p *Page) Diff() template.HTML {
+	name, err := url.PathUnescape(p.Name)
+	if err != nil {
+		return template.HTML("Cannot unescape " + p.Name)
+	}
+	a := name + ".md~"
+	t1, err := os.ReadFile(a)
+	if err != nil {
+		return template.HTML("Cannot read " + a + ", so the page is new.")
+	}
+	b := name + ".md"
+	t2, err := os.ReadFile(b)
+	if err != nil {
+		return template.HTML("Cannot read " + b + ", so the page was deleted.")
+	}
+	dmp := diffmatchpatch.New()
+	diffs := dmp.DiffMain(string(t1), string(t2), false)
+	return template.HTML(diff2html(dmp.DiffCleanupSemantic(diffs)))
+}
+
+func diff2html(diffs []diffmatchpatch.Diff) string {
+	var buff bytes.Buffer
+	for _, item := range diffs {
+		text := strings.ReplaceAll(html.EscapeString(item.Text), "\n", "<br>")
+		switch item.Type {
+		case diffmatchpatch.DiffInsert:
+			_, _ = buff.WriteString("<ins>")
+			_, _ = buff.WriteString(text)
+			_, _ = buff.WriteString("</ins>")
+		case diffmatchpatch.DiffDelete:
+			_, _ = buff.WriteString("<del>")
+			_, _ = buff.WriteString(text)
+			_, _ = buff.WriteString("</del>")
+		case diffmatchpatch.DiffEqual:
+			_, _ = buff.WriteString("<span>")
+			_, _ = buff.WriteString(text)
+			_, _ = buff.WriteString("</span>")
+		}
+	}
+	return buff.String()
+}

diff.html

@@ -0,0 +1,28 @@
+<!DOCTYPE html>
+<html lang="{{.Language}}">
+  <head>
+    <meta charset="utf-8">
+    <meta name="format-detection" content="telephone=no">
+    <meta name="viewport" content="width=device-width">
+    <title>{{.Title}}</title>
+    <style>
+html { max-width: 65ch; padding: 1ch; margin: auto; color: #111; background-color: #ffe; }
+body { hyphens: auto; }
+del  { background-color: #fab }
+ins  { background-color: #af8 }
+pre { white-space: normal; background-color: white; border: 1px solid #eee; padding: 1ch }
+    </style>
+  </head>
+  <body>
+    <header>
+      <a href="/view/{{.Name}}">Back</a>
+    </header>
+    <main id="main">
+      <h1>{{.Title}}</h1>
+      <p>This is the diff between <a href="/view/{{.Name}}.md~">the backup</a> and <a href="/view/{{.Name}}.md">the current copy</a>.</p>
+      <pre>
+{{.Diff}}
+      </pre>
+    </main>
+  </body>
+</html>

diff_test.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"github.com/stretchr/testify/assert"
+	"os"
+	"testing"
+	"time"
+)
+
+func TestDiff(t *testing.T) {
+	cleanup(t, "testdata/diff")
+	index.load()
+	s := `# Bread
+
+The oven breathes
+Fills us with the thought of bread
+Oh so fresh, so warm.`
+	r := `# Bread
+
+The oven whispers
+Fills us with the thought of bread
+Oh so fresh, so warm.`
+	p := &Page{Name: "testdata/diff/bread", Body: []byte(s)}
+	p.save()
+	p.Body = []byte(r)
+	p.save()
+	body := assert.HTTPBody(makeHandler(diffHandler, true),
+		"GET", "/diff/testdata/diff/bread", nil)
+	assert.Contains(t, body, `<del>breathe</del>`)
+	assert.Contains(t, body, `<ins>whisper</ins>`)
+}
+
+func TestDiffPercentEncoded(t *testing.T) {
+	cleanup(t, "testdata/diff")
+	index.load()
+	s := `# Coup de Gras
+
+Playing D&D
+We talk about a killing
+Mispronouncing words`
+	r := `# Coup de Grace
+
+Playing D&D
+We talk about a killing
+Mispronouncing words`
+	p := &Page{Name: "testdata/diff/coup de grace", Body: []byte(s)}
+	p.save()
+	p.Body = []byte(r)
+	p.save()
+	body := assert.HTTPBody(makeHandler(diffHandler, true),
+		"GET", "/diff/testdata/diff/coup%20de%20grace", nil)
+	assert.Contains(t, body, `<del>s</del>`)
+	assert.Contains(t, body, `<ins>ce</ins>`)
+}
+
+func TestDiffBackup(t *testing.T) {
+	cleanup(t, "testdata/backup")
+	s := `# Cold Rooms
+
+I shiver at home
+the monitor glares and moans
+fear or cold, who knows?`
+	r := `# Cold Rooms
+
+I shiver at home
+the monitor glares and moans
+I hate the machine!`
+	u := `# Cold Rooms
+
+I shiver at home
+the monitor glares and moans
+my grey heart grows cold`
+	p := &Page{Name: "testdata/backup/cold", Body: []byte(s)}
+	p.save()
+	p = &Page{Name: "testdata/backup/cold", Body: []byte(r)}
+	p.save()
+	body := string(p.Diff())
+	// diff from s to r:
+	assert.Contains(t, body, `<del>fear or cold, who knows?</del>`)
+	assert.Contains(t, body, `<ins>I hate the machine!</ins>`)
+	p = &Page{Name: "testdata/backup/cold", Body: []byte(u)}
+	p.save()
+	body = string(p.Diff())
+	// diff from s to u since r was not 60 min or older
+	assert.Contains(t, body, `<del>fear or cold, who knows?</del>`)
+	assert.Contains(t, body, `<ins>my grey heart grows cold</ins>`)
+	// set timestamp 2h in the past
+	ts := time.Now().Add(-2 * time.Hour)
+	assert.NoError(t, os.Chtimes("testdata/backup/cold.md~", ts, ts))
+	p = &Page{Name: "testdata/backup/cold", Body: []byte(r)}
+	p.save()
+	body = string(p.Diff())
+	// diff from u to r:
+	assert.Contains(t, body, `<del>my grey heart grows cold</del>`)
+	assert.Contains(t, body, `<ins>I hate the machine!</ins>`)
+}

edit.html

@@ -6,7 +6,7 @@
     <meta name="viewport" content="width=device-width">
     <title>Editing {{.Title}}</title>
     <style>
-html { max-width: 70ch; padding: 2ch; margin: auto; color: #111; background: #ffe; }
+html { max-width: 70ch; padding: 2ch; margin: auto; color: #111; background-color: #ffe; }
 form, textarea { width: 100%; }
     </style>
   </head>
@@ -16,6 +16,7 @@ form, textarea { width: 100%; }
       <textarea name="body" rows="20" cols="80" placeholder="# Title
 
 Text" lang="" autofocus>{{printf "%s" .Body}}</textarea>
+      <p><label><input type="checkbox" name="notify" checked> Add link to <a href="/view/changes">the list of changes</a>.</label></p>
       <p><input type="submit" value="Save">
         <a href="/view/{{.Name}}"><button type="button">Cancel</button></a></p>
     </form>

edit_save.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"log"
 	"net/http"
 )
 
@@ -28,5 +29,11 @@ func saveHandler(w http.ResponseWriter, r *http.Request, name string) {
 		http.Error(w, err.Error(), http.StatusInternalServerError)
 		return
 	}
+	if r.FormValue("notify") == "on" {
+		err = p.notify()
+		if err != nil {
+			log.Println("notify:", err)
+		}
+	}
 	http.Redirect(w, r, "/view/"+name, http.StatusFound)
 }

edit_save_test.go

@@ -4,24 +4,59 @@ import (
 	"github.com/stretchr/testify/assert"
 	"net/url"
 	"os"
-	"regexp"
 	"testing"
+	"time"
 )
 
-// wipes testdata
 func TestEditSave(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/save")
 
 	data := url.Values{}
 	data.Set("body", "Hallo!")
 
-	HTTPRedirectTo(t, makeHandler(viewHandler, true), "GET", "/view/testdata/alex", nil, "/edit/testdata/alex")
-	assert.HTTPStatusCode(t, makeHandler(editHandler, true), "GET", "/edit/testdata/alex", nil, 200)
-	HTTPRedirectTo(t, makeHandler(saveHandler, true), "POST", "/save/testdata/alex", data, "/view/testdata/alex")
-	assert.Regexp(t, regexp.MustCompile("Hallo!"),
-		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/alex", nil))
-
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+	// View of the non-existing page redirects to the edit page
+	HTTPRedirectTo(t, makeHandler(viewHandler, true),
+		"GET", "/view/testdata/save/alex", nil, "/edit/testdata/save/alex")
+	// Edit page can be fetched
+	assert.HTTPStatusCode(t, makeHandler(editHandler, true),
+		"GET", "/edit/testdata/save/alex", nil, 200)
+	// Posting to the save URL saves a page
+	HTTPRedirectTo(t, makeHandler(saveHandler, true),
+		"POST", "/save/testdata/save/alex", data, "/view/testdata/save/alex")
+	// Page now contains the text
+	assert.Contains(t, assert.HTTPBody(makeHandler(viewHandler, true),
+		"GET", "/view/testdata/save/alex", nil),
+		"Hallo!")
+	// Delete the page and you're sent to the empty page
+	data.Set("body", "")
+	HTTPRedirectTo(t, makeHandler(saveHandler, true),
+		"POST", "/save/testdata/save/alex", data, "/view/testdata/save/alex")
+	// Viewing the non-existing page redirects to the edit page (like in the beginning)
+	HTTPRedirectTo(t, makeHandler(viewHandler, true),
+		"GET", "/view/testdata/save/alex", nil, "/edit/testdata/save/alex")
+}
+
+func TestEditSaveChanges(t *testing.T) {
+	cleanup(t, "testdata/notification", "changes.md")
+	restore(t, "index.md")
+	os.Remove("changes.md")
+	data := url.Values{}
+	data.Set("body", "Hallo!")
+	data.Add("notify", "on")
+	// Posting to the save URL saves a page
+	HTTPRedirectTo(t, makeHandler(saveHandler, true),
+		"POST", "/save/testdata/notification/2023-10-28-alex",
+		data, "/view/testdata/notification/2023-10-28-alex")
+	// The changes.md file was created
+	s, err := os.ReadFile("changes.md")
+	assert.NoError(t, err)
+	d := time.Now().Format(time.DateOnly)
+	assert.Equal(t, "# Changes\n\n## "+d+
+		"\n* [testdata/notification/2023-10-28-alex](testdata/notification/2023-10-28-alex)\n",
+		string(s))
+	// Link added to index.md file
+	s, err = os.ReadFile("index.md")
+	assert.NoError(t, err)
+	assert.Contains(t, string(s),
+		"\n* [testdata/notification/2023-10-28-alex](testdata/notification/2023-10-28-alex)\n")
 }

feed.go

@@ -1,11 +1,10 @@
 package main
 
 import (
+	"bytes"
 	"github.com/gomarkdown/markdown"
 	"github.com/gomarkdown/markdown/ast"
-	"github.com/gomarkdown/markdown/parser"
 	"html/template"
-	"bytes"
 	"os"
 	"path"
 	"time"
@@ -26,7 +25,7 @@ func feed(p *Page, ti time.Time) *Feed {
 	feed.Name = p.Name
 	feed.Title = p.Title
 	feed.Date = ti.Format(time.RFC1123Z)
-	parser := parser.New()
+	parser, _ := wikiParser()
 	doc := markdown.Parse(p.Body, parser)
 	items := make([]Item, 0)
 	inListItem := false

feed_test.go

@@ -2,22 +2,20 @@ package main
 
 import (
 	"github.com/stretchr/testify/assert"
-	"os"
 	"testing"
 )
 
 func TestFeed(t *testing.T) {
-	assert.Contains(t, 
+	assert.Contains(t,
 		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/index.rss", nil),
 		"Welcome to Oddµ")
 }
 
-// wipes testdata
 func TestFeedItems(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/feed")
 	index.load()
-	
-	p1 := &Page{Name: "testdata/cactus", Body: []byte(`# Cactus
+
+	p1 := &Page{Name: "testdata/feed/cactus", Body: []byte(`# Cactus
 Green head and white hair
 A bench in the evening sun
 Unmoved by the news
@@ -25,7 +23,7 @@ Unmoved by the news
 #Succulent`)}
 	p1.save()
 
-	p2 := &Page{Name: "testdata/dragon", Body: []byte(`# Dragon
+	p2 := &Page{Name: "testdata/feed/dragon", Body: []byte(`# Dragon
 My palm tree grows straight
 Up and up to touch the sky
 Ignoring the roof
@@ -33,14 +31,14 @@ Ignoring the roof
 #Palmtree`)}
 	p2.save()
 
-	p3 := &Page{Name: "testdata/plants", Body: []byte(`# Plants
+	p3 := &Page{Name: "testdata/feed/plants", Body: []byte(`# Plants
 Writing poems about plants.
 
 * [My Cactus](cactus)
 * [My Dragon Tree](dragon)`)}
 	p3.save()
 
-	body := assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/plants.rss", nil)
+	body := assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/feed/plants.rss", nil)
 	assert.Contains(t, body, "<title>Plants</title>")
 	assert.Contains(t, body, "<title>Cactus</title>")
 	assert.Contains(t, body, "<title>Dragon</title>")
@@ -48,8 +46,4 @@ Writing poems about plants.
 	assert.Contains(t, body, "&lt;h1&gt;Dragon&lt;/h1&gt;")
 	assert.Contains(t, body, "<category>Succulent</category>")
 	assert.Contains(t, body, "<category>Palmtree</category>")
-
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
 }

go.mod

@@ -4,26 +4,33 @@ go 1.21.0
 
 require (
 	github.com/anthonynsimon/bild v0.13.0
-	github.com/dgryski/go-trigram v0.0.0-20160407183937-79ec494e1ad0
-	github.com/gomarkdown/markdown v0.0.0-20230912175223-14b07df9d538
+	github.com/charmbracelet/lipgloss v0.8.0
+	github.com/gomarkdown/markdown v0.0.0-20230922112808-5421fefb8386
 	github.com/google/subcommands v1.2.0
 	github.com/hexops/gotextdiff v1.0.3
 	github.com/microcosm-cc/bluemonday v1.0.25
 	github.com/pemistahl/lingua-go v1.4.0
+	github.com/sergi/go-diff v1.3.1
 	github.com/stretchr/testify v1.8.4
+	golang.org/x/exp v0.0.0-20221106115401-f9659909a136
 )
 
 require (
+	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
 	github.com/aymerick/douceur v0.2.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/gorilla/css v1.0.0 // indirect
-	github.com/kr/pretty v0.1.0 // indirect
+	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
+	github.com/mattn/go-isatty v0.0.18 // indirect
+	github.com/mattn/go-runewidth v0.0.14 // indirect
+	github.com/muesli/reflow v0.3.0 // indirect
+	github.com/muesli/termenv v0.15.2 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/rivo/uniseg v0.2.0 // indirect
 	github.com/shopspring/decimal v1.3.1 // indirect
-	golang.org/x/exp v0.0.0-20221106115401-f9659909a136 // indirect
-	golang.org/x/image v0.0.0-20190703141733-d6a02ce849c9 // indirect
-	golang.org/x/net v0.12.0 // indirect
+	golang.org/x/image v0.10.0 // indirect
+	golang.org/x/net v0.17.0 // indirect
+	golang.org/x/sys v0.13.0 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect
-	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -2,20 +2,23 @@ github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03
 github.com/anthonynsimon/bild v0.13.0 h1:mN3tMaNds1wBWi1BrJq0ipDBhpkooYfu7ZFSMhXt1C8=
 github.com/anthonynsimon/bild v0.13.0/go.mod h1:tpzzp0aYkAsMi1zmfhimaDyX1xjn2OUc1AJZK/TF0AE=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
+github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiErDT4WkJ2k=
+github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/aymerick/douceur v0.2.0 h1:Mv+mAeH1Q+n9Fr+oyamOlAkUNPWPlA8PPGR0QAaYuPk=
 github.com/aymerick/douceur v0.2.0/go.mod h1:wlT5vV2O3h55X9m7iVYN0TBM0NH/MmbLnd30/FjWUq4=
+github.com/charmbracelet/lipgloss v0.8.0 h1:IS00fk4XAHcf8uZKc3eHeMUTCxUH6NkaTrdyCQk84RU=
+github.com/charmbracelet/lipgloss v0.8.0/go.mod h1:p4eYUZZJ/0oXTuCQKFF8mqyKCz0ja6y+7DniDDw5KKU=
 github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
 github.com/coreos/go-etcd v2.0.0+incompatible/go.mod h1:Jez6KQU2B/sWsbdaef3ED8NzMklzPG4d5KIOhIy30Tk=
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/dgryski/go-trigram v0.0.0-20160407183937-79ec494e1ad0 h1:b+7JSiBM+hnLQjP/lXztks5hnLt1PS46hktG9VOJgzo=
-github.com/dgryski/go-trigram v0.0.0-20160407183937-79ec494e1ad0/go.mod h1:qzKC/DpcxK67zaSHdCmIv3L9WJViHVinYXN2S7l3RM8=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
-github.com/gomarkdown/markdown v0.0.0-20230912175223-14b07df9d538 h1:ePDpFu7l0QUV46/9A7icfL2wvIOzTJLCWh4RO2NECzE=
-github.com/gomarkdown/markdown v0.0.0-20230912175223-14b07df9d538/go.mod h1:JDGcbDT52eL4fju3sZ4TeHGsQwhG9nbDV21aMyhwPoA=
+github.com/gomarkdown/markdown v0.0.0-20230922112808-5421fefb8386 h1:EcQR3gusLHN46TAD+G+EbaaqJArt5vHhNpXAa12PQf4=
+github.com/gomarkdown/markdown v0.0.0-20230922112808-5421fefb8386/go.mod h1:JDGcbDT52eL4fju3sZ4TeHGsQwhG9nbDV21aMyhwPoA=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
 github.com/google/go-cmp v0.5.8/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
@@ -32,17 +35,33 @@ github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORN
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
+github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
+github.com/mattn/go-isatty v0.0.18 h1:DOKFKCQ7FNG2L1rbrmstDN4QVRdS89Nkh85u68Uwp98=
+github.com/mattn/go-isatty v0.0.18/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-runewidth v0.0.12/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
+github.com/mattn/go-runewidth v0.0.14 h1:+xnbZSEeDbOIg5/mE6JF0w6n9duR1l3/WmbinWVwUuU=
+github.com/mattn/go-runewidth v0.0.14/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
 github.com/microcosm-cc/bluemonday v1.0.25 h1:4NEwSfiJ+Wva0VxN5B8OwMicaJvD8r9tlJWm9rtloEg=
 github.com/microcosm-cc/bluemonday v1.0.25/go.mod h1:ZIOjCQp1OrzBBPIJmfX4qDYFuhU02nx4bn030ixfHLE=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
+github.com/muesli/reflow v0.3.0 h1:IFsN6K9NfGtjeggFP+68I4chLZV2yIKsXJFNZ+eWh6s=
+github.com/muesli/reflow v0.3.0/go.mod h1:pbwTDkVPibjO2kyvBQRBxTWEEGDGq0FlB1BIKtnHY/8=
+github.com/muesli/termenv v0.15.2 h1:GohcuySI0QmI3wN8Ok9PtKGkgkFIk7y6Vpb5PvrY+Wo=
+github.com/muesli/termenv v0.15.2/go.mod h1:Epx+iuz8sNs7mNKhxzH4fWXGNpZwUaJKRS1noLXviQ8=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/pemistahl/lingua-go v1.4.0 h1:ifYhthrlW7iO4icdubwlduYnmwU37V1sbNrwhKBR4rM=
 github.com/pemistahl/lingua-go v1.4.0/go.mod h1:ECuM1Hp/3hvyh7k8aWSqNCPlTxLemFZsRjocUf3KgME=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
+github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=
+github.com/sergi/go-diff v1.3.1 h1:xkr+Oxo4BOQKmkn/B9eMK0g5Kg/983T9DqqPHwYqD+8=
+github.com/sergi/go-diff v1.3.1/go.mod h1:aMJSSKb2lpPvRNec0+w3fl7LP9IOFzdc9Pa4NFbPK1I=
 github.com/shopspring/decimal v1.3.1 h1:2Usl1nmF/WZucqkFZhnfFYxxxu8LG21F6nPQBE5gKV8=
 github.com/shopspring/decimal v1.3.1/go.mod h1:DKyhrW/HYNuLGql+MJL6WCR6knT2jwCFRcu2hWCYk4o=
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
@@ -51,20 +70,56 @@ github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tL
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v1.0.3/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/viper v1.3.2/go.mod h1:ZiWeW+zYFKm7srdB9IoDzzZXaJaI5eL9QjNiN/DMA2s=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
+github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/exp v0.0.0-20221106115401-f9659909a136 h1:Fq7F/w7MAa1KJ5bt2aJ62ihqp9HDcRuyILskkpIAurw=
 golang.org/x/exp v0.0.0-20221106115401-f9659909a136/go.mod h1:CxIveKay+FTh1D0yPZemJVgC/95VzuuOLq5Qi4xnoYc=
-golang.org/x/image v0.0.0-20190703141733-d6a02ce849c9 h1:uc17S921SPw5F2gJo7slQ3aqvr2RwpL7eb3+DZncu3s=
 golang.org/x/image v0.0.0-20190703141733-d6a02ce849c9/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
-golang.org/x/net v0.12.0 h1:cfawfvKITfUsFCeJIHJrbSxpeu/E81khclypR0GVT50=
-golang.org/x/net v0.12.0/go.mod h1:zEVYFnQC7m/vmpQFELhcD1EWkZlX69l4oqgmer6hfKA=
+golang.org/x/image v0.10.0 h1:gXjUUtwtx5yOE0VKWq1CH4IJAClq4UGgUA3i+rpON9M=
+golang.org/x/image v0.10.0/go.mod h1:jtrku+n79PfroUbvDdeUWMAI+heR786BofxrbiSF+J0=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
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+golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
+golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
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+golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
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+golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
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+golang.org/x/text v0.11.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
 google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=
@@ -73,5 +128,6 @@ gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

html_cmd.go

@@ -14,7 +14,7 @@ type htmlCmd struct {
 }
 
 func (*htmlCmd) Name() string     { return "html" }
-func (*htmlCmd) Synopsis() string { return "Render a page as HTML." }
+func (*htmlCmd) Synopsis() string { return "render a page as HTML" }
 func (*htmlCmd) Usage() string {
 	return `html [-view] <page name>:
   Render a page as HTML.
@@ -30,10 +30,10 @@ func (cmd *htmlCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}
 }
 
 func htmlCli(w io.Writer, useTemplate bool, args []string) subcommands.ExitStatus {
-		for _, arg := range args {
+	for _, arg := range args {
 		p, err := loadPage(arg)
 		if err != nil {
-			fmt.Fprintf(w, "Cannot load %s: %s\n", arg, err)
+			fmt.Fprintf(os.Stderr, "Cannot load %s: %s\n", arg, err)
 			return subcommands.ExitFailure
 		}
 		initAccounts()
@@ -43,7 +43,7 @@ func htmlCli(w io.Writer, useTemplate bool, args []string) subcommands.ExitStatu
 			t := "view.html"
 			err := templates.ExecuteTemplate(w, t, p)
 			if err != nil {
-				fmt.Fprintf(w, "Cannot execute %s template for %s: %s\n", t, arg, err)
+				fmt.Fprintf(os.Stderr, "Cannot execute %s template for %s: %s\n", t, arg, err)
 				return subcommands.ExitFailure
 			}
 		} else {

html_cmd_test.go

@@ -2,9 +2,9 @@ package main
 
 import (
 	"bytes"
+	"github.com/google/subcommands"
 	"github.com/stretchr/testify/assert"
 	"testing"
-	"github.com/google/subcommands"
 )
 
 func TestHtmlCmd(t *testing.T) {
@@ -15,7 +15,9 @@ func TestHtmlCmd(t *testing.T) {
 
 <p>Hello! 🙃</p>
 
-<p>Check out the <a href="README" rel="nofollow">README</a>.</p>
+<p>Check out the <a href="README">README</a>.</p>
+
+<p>Or <a href="test">create a new page</a>.</p>
 
 `
 	assert.Equal(t, r, b.String())

index.go

@@ -1,43 +1,98 @@
+// Read Artem Krylysov's blog post on full text search as an
+// introduction.
+// https://artem.krylysov.com/blog/2020/07/28/lets-build-a-full-text-search-engine/
+
 package main
 
 import (
-	trigram "github.com/dgryski/go-trigram"
+	"golang.org/x/exp/constraints"
 	"io/fs"
+	"log"
 	"path/filepath"
+	"sort"
 	"strings"
 	"sync"
 )
 
+type docid uint
+
 // Index contains the two maps used for search. Make sure to lock and
 // unlock as appropriate.
 type Index struct {
 	sync.RWMutex
 
-	// index is a struct containing the trigram index for search.
-	// It is generated at startup and updated after every page
-	// edit. The index is case-insensitive.
-	index trigram.Index
+	// next_id is the number of the next document added to the index
+	next_id docid
 
-	// documents is a map, mapping document ids of the index to
-	// page names.
-	documents map[trigram.DocID]string
+	// index is an inverted index mapping tokens to document ids.
+	token map[string][]docid
 
-	// names is a map, mapping page names to titles.
+	// documents is a map, mapping document ids to page names.
+	documents map[docid]string
+
+	// titles is a map, mapping page names to titles.
 	titles map[string]string
 }
 
-// idx is the global Index per wiki.
 var index Index
 
 // reset resets the Index. This assumes that the index is locked!
 func (idx *Index) reset() {
-	idx.index = nil
+	idx.token = nil
 	idx.documents = nil
 	idx.titles = nil
 }
 
+// addDocument adds the text as a new document. This assumes that the
+// index is locked!
+func (idx *Index) addDocument(text []byte) docid {
+	id := idx.next_id
+	idx.next_id++
+	for _, token := range hashtags(text) {
+		ids := idx.token[token]
+		// Don't add same ID more than once. Checking the last
+		// position of the []docid works because the id is
+		// always a new one, i.e. the last one, if at all.
+		if ids != nil && ids[len(ids)-1] == id {
+			continue
+		}
+		idx.token[token] = append(ids, id)
+	}
+	return id
+}
+
+// deleteDocument deletes the text as a new document. The id can no
+// longer be used. This assumes that the index is locked!
+func (idx *Index) deleteDocument(text []byte, id docid) {
+	for _, token := range hashtags(text) {
+		ids := index.token[token]
+		// Tokens can appear multiple times in a text but they
+		// can only be deleted once. deleted.
+		if ids == nil {
+			continue
+		}
+		// If the token appears only in this document, remove
+		// the whole entry.
+		if len(ids) == 1 && ids[0] == id {
+			delete(index.token, token)
+			continue
+		}
+		// Otherwise, remove the token from the index.
+		i := sort.Search(len(ids), func(i int) bool { return ids[i] >= id })
+		if i != -1 && i < len(ids) && ids[i] == id {
+			copy(ids[i:], ids[i+1:])
+			index.token[token] = ids[:len(ids)-1]
+			continue
+		}
+		// If none of the above, then our docid wasn't
+		// indexed. This shouldn't happen, either.
+		log.Printf("The index for token %s does not contain doc id %d", token, id)
+	}
+	delete(index.documents, id)
+}
+
 // add reads a file and adds it to the index. This must happen while
-// the idx is locked, which is true when called from loadIndex.
+// the idx is locked.
 func (idx *Index) add(path string, info fs.FileInfo, err error) error {
 	if err != nil {
 		return err
@@ -52,7 +107,8 @@ func (idx *Index) add(path string, info fs.FileInfo, err error) error {
 		return err
 	}
 	p.handleTitle(false)
-	id := idx.index.Add(strings.ToLower(string(p.Body)))
+
+	id := idx.addDocument(p.Body)
 	idx.documents[id] = p.Name
 	idx.titles[p.Name] = p.Title
 	return nil
@@ -63,8 +119,8 @@ func (idx *Index) add(path string, info fs.FileInfo, err error) error {
 func (idx *Index) load() (int, error) {
 	idx.Lock()
 	defer idx.Unlock()
-	idx.index = make(trigram.Index)
-	idx.documents = make(map[trigram.DocID]string)
+	idx.token = make(map[string][]docid)
+	idx.documents = make(map[docid]string)
 	idx.titles = make(map[string]string)
 	err := filepath.Walk(".", idx.add)
 	if err != nil {
@@ -75,15 +131,23 @@ func (idx *Index) load() (int, error) {
 	return n, nil
 }
 
+// dump prints the index to the log for debugging. Must already be readlocked.
+func (idx *Index) dump() {
+	index.RLock()
+	defer index.RUnlock()
+	for token, ids := range idx.token {
+		log.Printf("%s: %v", token, ids)
+	}
+}
+
 // updateIndex updates the index for a single page. The old text is
 // loaded from the disk and removed from the index first, if it
 // exists.
 func (p *Page) updateIndex() {
 	index.Lock()
 	defer index.Unlock()
-	var id trigram.DocID
-	// This function does not rely on files actually existing, so
-	// let's quickly find the document id.
+	var id docid
+	// Reverse lookup! At least it's in memory.
 	for docId, name := range index.documents {
 		if name == p.Name {
 			id = docId
@@ -91,33 +155,100 @@ func (p *Page) updateIndex() {
 		}
 	}
 	if id == 0 {
-		id = index.index.Add(strings.ToLower(string(p.Body)))
+		id = index.addDocument(p.Body)
 		index.documents[id] = p.Name
+		index.titles[p.Name] = p.Title
 	} else {
-		o, err := loadPage(p.Name)
-		if err == nil {
-			index.index.Delete(strings.ToLower(string(o.Body)), id)
-			o.handleTitle(false)
-			delete(index.titles, o.Title)
+		if o, err := loadPage(p.Name); err == nil {
+			index.deleteDocument(o.Body, id)
 		}
-		index.index.Insert(strings.ToLower(string(p.Body)), id)
+		// Do not reuse the old id. We need a new one for
+		// indexing to work.
+		id = index.addDocument(p.Body)
+		// The page name stays the same but the title may have
+		// changed.
+		index.documents[id] = p.Name
 		p.handleTitle(false)
 		index.titles[p.Name] = p.Title
 	}
 }
 
-// searchDocuments searches the index for a string. This requires the
-// index to be locked.
-func searchDocuments(q string) []string {
-	words := strings.Fields(strings.ToLower(q))
-	var trigrams []trigram.T
-	for _, word := range words {
-		trigrams = trigram.Extract(word, trigrams)
+// removeFromIndex removes the page from the index. Do this when
+// deleting a page.
+func (p *Page) removeFromIndex() {
+	index.Lock()
+	defer index.Unlock()
+	var id docid
+	// Reverse lookup! At least it's in memory.
+	for docId, name := range index.documents {
+		if name == p.Name {
+			id = docId
+			break
+		}
 	}
-	ids := index.index.QueryTrigrams(trigrams)
-	names := make([]string, len(ids))
-	for i, id := range ids {
-		names[i] = index.documents[id]
+	if id == 0 {
+		log.Printf("Page %s is not indexed", p.Name)
+		return
+	}
+	o, err := loadPage(p.Name)
+	if err != nil {
+		log.Printf("Page %s cannot removed from the index: %s", p.Name, err)
+		return
+	}
+	index.deleteDocument(o.Body, id)
+}
+
+// search searches the index for a query string and returns page
+// names.
+func (idx *Index) search(q string) []string {
+	index.RLock()
+	defer index.RUnlock()
+	names := make([]string, 0)
+	hashtags := hashtags([]byte(q))
+	if len(hashtags) > 0 {
+		var r []docid
+		for _, token := range hashtags {
+			if ids, ok := idx.token[token]; ok {
+				if r == nil {
+					r = ids
+				} else {
+					r = intersection(r, ids)
+				}
+			} else {
+				// Token doesn't exist therefore abort search.
+				return nil
+			}
+		}
+		for _, id := range r {
+			names = append(names, idx.documents[id])
+		}
+	} else {
+		for _, name := range idx.documents {
+			names = append(names, name)
+		}
 	}
 	return names
 }
+
+// intersection returns the set intersection between a and b.
+// a and b have to be sorted in ascending order and contain no duplicates.
+func intersection[T constraints.Ordered](a []T, b []T) []T {
+	maxLen := len(a)
+	if len(b) > maxLen {
+		maxLen = len(b)
+	}
+	r := make([]T, 0, maxLen)
+	var i, j int
+	for i < len(a) && j < len(b) {
+		if a[i] < b[j] {
+			i++
+		} else if a[i] > b[j] {
+			j++
+		} else {
+			r = append(r, a[i])
+			i++
+			j++
+		}
+	}
+	return r
+}

index.md

@@ -2,4 +2,6 @@
 
 Hello! 🙃
 
-Check out the [README](README).
+Check out the [[README]].
+
+Or [create a new page](test).

index_test.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"github.com/stretchr/testify/assert"
-	"os"
 	"strings"
 	"testing"
 )
@@ -11,7 +10,7 @@ import (
 func TestIndex(t *testing.T) {
 	index.load()
 	q := "Oddµ"
-	pages, _, _ := search(q, 1)
+	pages, _ := search(q, "", 1, false)
 	assert.NotZero(t, len(pages))
 	for _, p := range pages {
 		assert.NotContains(t, p.Title, "<b>")
@@ -23,19 +22,19 @@ func TestIndex(t *testing.T) {
 func TestSearchHashtag(t *testing.T) {
 	index.load()
 	q := "#like_this"
-	pages, _, _ := search(q, 1)
+	pages, _ := search(q, "", 1, false)
 	assert.NotZero(t, len(pages))
 }
 
 func TestIndexUpdates(t *testing.T) {
-	name := "test"
-	_ = os.Remove(name + ".md")
+	cleanup(t, "testdata/update")
+	name := "testdata/update/test"
 	index.load()
-	p := &Page{Name: name, Body: []byte("This is a test.")}
+	p := &Page{Name: name, Body: []byte("#Old Name\nThis is a test.")}
 	p.save()
 
 	// Find the phrase
-	pages, _, _ := search("This is a test", 1)
+	pages, _ := search("This is a test", "", 1, false)
 	found := false
 	for _, p := range pages {
 		if p.Name == name {
@@ -46,7 +45,7 @@ func TestIndexUpdates(t *testing.T) {
 	assert.True(t, found)
 
 	// Find the phrase, case insensitive
-	pages, _, _ = search("this is a test", 1)
+	pages, _ = search("this is a test", "", 1, false)
 	found = false
 	for _, p := range pages {
 		if p.Name == name {
@@ -57,7 +56,7 @@ func TestIndexUpdates(t *testing.T) {
 	assert.True(t, found)
 
 	// Find some words
-	pages, _, _ = search("this test", 1)
+	pages, _ = search("this test", "", 1, false)
 	found = false
 	for _, p := range pages {
 		if p.Name == name {
@@ -68,9 +67,9 @@ func TestIndexUpdates(t *testing.T) {
 	assert.True(t, found)
 
 	// Update the page and no longer find it with the old phrase
-	p = &Page{Name: name, Body: []byte("Guvf vf n grfg.")}
+	p = &Page{Name: name, Body: []byte("# New page\nGuvf vf n grfg.")}
 	p.save()
-	pages, _, _ = search("This is a test", 1)
+	pages, _ = search("This is a test", "", 1, false)
 	found = false
 	for _, p := range pages {
 		if p.Name == name {
@@ -81,7 +80,7 @@ func TestIndexUpdates(t *testing.T) {
 	assert.False(t, found)
 
 	// Find page using a new word
-	pages, _, _ = search("Guvf", 1)
+	pages, _ = search("Guvf", "", 1, false)
 	found = false
 	for _, p := range pages {
 		if p.Name == name {
@@ -91,7 +90,8 @@ func TestIndexUpdates(t *testing.T) {
 	}
 	assert.True(t, found)
 
-	t.Cleanup(func() {
-		_ = os.Remove(name + ".md")
-	})
+	// Make sure the title was updated
+	index.RLock()
+	defer index.RUnlock()
+	assert.Equal(t, index.titles[name], "New page")
 }

man/Makefile

@@ -1,5 +1,6 @@
-docs: oddmu.1 oddmu.5 oddmu-templates.5 oddmu-apache.5 oddmu.service.5 oddmu-replace.1 \
-	oddmu-search.1 oddmu-search.7 oddmu-html.1
+docs: oddmu-apache.5 oddmu-html.1 oddmu-missing.1 oddmu-notify.1 \
+	oddmu-replace.1 oddmu-search.1 oddmu-search.7 oddmu-static.1 \
+	oddmu-templates.5 oddmu.1 oddmu.5 oddmu.service.5
 
 oddmu%: oddmu%.txt
 	scdoc < $< > $@

man/oddmu-apache.5

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU-APACHE" "5" "2023-09-18"
+.TH "ODDMU-APACHE" "5" "2023-11-05"
 .PP
 .SH NAME
 .PP
@@ -13,24 +13,22 @@ oddmu-apache - how to setup Apache as a reverse proxy for Oddmu
 .PP
 .SS DESCRIPTION
 .PP
-The oddmu program serves the current working directory as a wiki on
-port 8080.\& This is an unpriviledged port so an ordinary use account
-can do this.\&
+The oddmu program serves the current working directory as a wiki on port 8080.\&
+This is an unpriviledged port so an ordinary user account can do this.\&
 .PP
-The best way to protect the wiki against vandalism and spam is to use
-a regular web server as reverse proxy.\& This page explains how to setup
-Apache on Debian to do this.\&
+The best way to protect the wiki against vandalism and spam is to use a regular
+web server as reverse proxy.\& This page explains how to setup Apache on Debian to
+do this.\&
 .PP
 .SS CONFIGURATION
 .PP
-HTTPS is not part of the wiki.\& You probably want to configure this in
-your webserver.\& I guess you could use stunnel, too.\& If you'\&re using
-Apache, you can use "mod_md" to manage your domain.\&
+HTTPS is not part of Oddmu.\& You probably want to configure this in your
+webserver.\& I guess you could use stunnel, too.\& If you'\&re using Apache, you can
+use "mod_md" to manage your domain.\&
 .PP
 In the example below, the site is configured in a file called
-"/etc/apache2/sites-available/500-transjovian.\&conf" and a link poins
-there from "/etc/apache2/sites-enabled".\& Create this link using
-\fIa2ensite\fR(1).\&
+"/etc/apache2/sites-available/500-transjovian.\&conf" and a link poins there from
+"/etc/apache2/sites-enabled".\& Create this link using \fIa2ensite\fR(1).\&
 .PP
 .nf
 .RS 4
@@ -46,22 +44,29 @@ MDCertificateAgreement accepted
     ServerAdmin alex@alexschroeder\&.ch
     ServerName transjovian\&.org
     SSLEngine on
-    ProxyPassMatch ^/(search|(view|edit|save|add|append|upload|drop)/(\&.*))?$ http://localhost:8080/$1
+    ProxyPassMatch "^/((view|diff|edit|save|add|append|upload|drop|search)/(\&.*))?$" "http://localhost:8080/$1"
 </VirtualHost>
 .fi
 .RE
 .PP
-First, it manages the domain, getting the necessary certificates.\& It
-redirects regular HTTP traffic from port 80 to port 443.\& It turns on
-the SSL engine for port 443.\& It proxies the requests for the wiki to
-port 8080.\&
+First, it manages the domain, getting the necessary certificates.\& It redirects
+regular HTTP traffic from port 80 to port 443.\& It turns on the SSL engine for
+port 443.\& It proxies the requests for Oddmu to port 8080.\& Importantly, it
+doesn'\&t send \fIall\fR the requests to Oddmu.\& This allows us to still host static
+files using the web server.\&
 .PP
-Thus, this is what happens:
+This is what happens:
 .PP
-\fB The user tells the browser to visit `transjovian.\&org`
-\fR The browser sends a request for `http://transjovian.\&org` (on port 80)
-\fB Apache redirects this to `https://transjovian.\&org/` by default (now on port 443)
-\fR This is proxied to `http://transjovian.\&org:8080/` (no encryption, on port 8080)
+.PD 0
+.IP \(bu 4
+The user tells the browser to visit "transjovian.\&org"
+.IP \(bu 4
+The browser sends a request for "http://transjovian.\&org" (on port 80)
+.IP \(bu 4
+Apache redirects this to "https://transjovian.\&org/" by default (now on port 443)
+.IP \(bu 4
+This is proxied to "http://transjovian.\&org:8080/" (now on port 8080)
+.PD
 .PP
 Restart the server, gracefully:
 .PP
@@ -71,18 +76,23 @@ apachectl graceful
 .fi
 .RE
 .PP
-To serve both HTTP and HTTPS, don'\&t redirect from the first virtual
-host to the second – instead just proxy to the wiki like you did for
-the second virtual host: use a copy of the "ProxyPassMatch" directive
-instead of "RewriteEngine on" and "RewriteRule".\&
+To serve both HTTP and HTTPS, don'\&t redirect from the first virtual host to the
+second – instead just proxy to the wiki like you did for the second virtual
+host: use a copy of the "ProxyPassMatch" directive instead of "RewriteEngine on"
+and "RewriteRule".\&
 .PP
 .SS Access
 .PP
-Access control is not part of the wiki.\& By default, the wiki is
-editable by all.\& This is most likely not what you want unless you'\&re
-running it stand-alone, unconnected to the Internet.\&
+Access control is not part of Oddmu.\& By default, the wiki is editable by all.\&
+This is most likely not what you want unless you'\&re running it stand-alone,
+unconnected to the Internet – a person memex on your laptop, for example.\&
 .PP
-Create a new password file called ".\&htpasswd" and add the user "alex":
+The following instructions create user accounts with passwords just for Oddmu.\&
+These users are not real users on the web server and don'\&t have access to a
+shell, mail, or any other service.\&
+.PP
+Create a new password file called ".\&htpasswd" and add the user "alex".\& The "-c"
+flag creates the file.\&
 .PP
 .nf
 .RS 4
@@ -91,9 +101,8 @@ htpasswd -c \&.htpasswd alex
 .fi
 .RE
 .PP
-To add more users, don'\&t use the "-c" option or you will overwrite it!\&
-.PP
-To add another user:
+To add more users, don'\&t use the "-c" option or you will overwrite the existing
+file.\& To add another user, use no option at all.\&
 .PP
 .nf
 .RS 4
@@ -101,7 +110,7 @@ htpasswd \&.htpasswd berta
 .fi
 .RE
 .PP
-To remove a user:
+To remove a user, use the "-D" option.\&
 .PP
 .nf
 .RS 4
@@ -109,9 +118,9 @@ htpasswd -D \&.htpasswd berta
 .fi
 .RE
 .PP
-Modify your site configuration and protect the "/edit/", "/save/",
-"/add/", "/append/", "/upload/" and "/drop/" URLs with a password by
-adding the following to your "<VirtualHost *:443>" section:
+Modify your site configuration and protect the "/edit/", "/save/", "/add/",
+"/append/", "/upload/" and "/drop/" URLs with a password by adding the following
+to your "<VirtualHost *:443>" section:
 .PP
 .nf
 .RS 4
@@ -126,10 +135,9 @@ adding the following to your "<VirtualHost *:443>" section:
 .PP
 .SS Serve static files
 .PP
-If you want to serve static files as well, add a document root to your
-webserver configuration.\& In this case, the document root is the
-directory where all the data files are.\& Apache will not serve files
-such as ".\&htpasswd".\&
+If you want to serve static files as well, add a document root to your webserver
+configuration.\& In this case, the document root is the directory where all the
+data files are.\& Apache does not serve files such as ".\&htpasswd".\&
 .PP
 .nf
 .RS 4
@@ -140,10 +148,10 @@ DocumentRoot /home/oddmu
 .fi
 .RE
 .PP
-Make sure that none of the subdirectories look like the wiki paths
-"/view/", "/edit/", "/save/", "/add/", "/append/", "/upload/",
-"/drop/" or "/search".\& For example, create a file called "robots.\&txt"
-containing the following, telling all robots that they'\&re not welcome.\&
+Make sure that none of the subdirectories look like the wiki paths "/view/",
+"/diff/", "/edit/", "/save/", "/add/", "/append/", "/upload/", "/drop/" or
+"/search/".\& For example, create a file called "robots.\&txt" containing the
+following, telling all robots that they'\&re not welcome.\&
 .PP
 .nf
 .RS 4
@@ -152,16 +160,18 @@ Disallow: /
 .fi
 .RE
 .PP
-You site now serves "/robots.\&txt" without interfering with the wiki,
-and without needing a wiki page.\&
+You site now serves "/robots.\&txt" without interfering with the wiki, and without
+needing a wiki page.\&
+.PP
+Another option would be to create a CSS file and use it with a <link> element in
+all the templates instead of relying on the <style> element.\&
 .PP
 .SS Different logins for different access rights
 .PP
-What if you have a site with various subdirectories and each
-subdirectory is for a different group of friends?\& You can set this up
-using your webserver.\& One way to do this is to require specific
-usernames (which must have a password in the password file mentioned
-above.\&
+What if you have a site with various subdirectories and each subdirectory is for
+a different group of friends?\& You can set this up using your webserver.\& One way
+to do this is to require specific usernames (which must have a password in the
+password file mentioned above.\&
 .PP
 This requires a valid login by the user "alex" or "berta":
 .PP
@@ -175,9 +185,8 @@ This requires a valid login by the user "alex" or "berta":
 .PP
 .SS Private wikis
 .PP
-Based on the above, you can prevent people from \fIreading\fR the wiki.\&
-The "LocationMatch" must cover the "/view/" URLs in order to protect
-\fBeverything\fR.\&
+Based on the above, you can prevent people from \fIreading\fR the wiki.\& The
+"LocationMatch" must cover all the URLs in order to protect everything.\&
 .PP
 .nf
 .RS 4
@@ -192,12 +201,11 @@ The "LocationMatch" must cover the "/view/" URLs in order to protect
 .PP
 .SS Virtual hosting
 .PP
-Virtual hosting in this context means that the program serves two
-different sites for two different domains from the same machine.\& Oddmu
-doesn'\&t support that, but your webserver does.\& Therefore, start an
-Oddmu instance for every domain name, each listening on a different
-port.\& Then set up your web server such that ever domain acts as a
-reverse proxy to a different Oddmu instance.\&
+Virtual hosting in this context means that the program serves two different
+sites for two different domains from the same machine.\& Oddmu doesn'\&t support
+that, but your webserver does.\& Therefore, start an Oddmu instance for every
+domain name, each listening on a different port.\& Then set up your web server
+such that ever domain acts as a reverse proxy to a different Oddmu instance.\&
 .PP
 .SH SEE ALSO
 .PP
@@ -215,6 +223,12 @@ https://httpd.\&apache.\&org/docs/current/mod/mod_proxy.\&html
 "Robot exclusion standard" on Wikipedia.\&
 https://en.\&wikipedia.\&org/wiki/Robot_exclusion_standard
 .PP
+"<style>: The Style Information element"
+https://developer.\&mozilla.\&org/en-US/docs/Web/HTML/Element/style
+.PP
+"<link>: The External Resource Link element"
+https://developer.\&mozilla.\&org/en-US/docs/Web/HTML/Element/link
+.PP
 .SH AUTHORS
 .PP
 Maintained by Alex Schroeder <alex@gnu.\&org>.\&

man/oddmu-apache.5.txt

@@ -6,24 +6,22 @@ oddmu-apache - how to setup Apache as a reverse proxy for Oddmu
 
 ## DESCRIPTION
 
-The oddmu program serves the current working directory as a wiki on
-port 8080. This is an unpriviledged port so an ordinary use account
-can do this.
+The oddmu program serves the current working directory as a wiki on port 8080.
+This is an unpriviledged port so an ordinary user account can do this.
 
-The best way to protect the wiki against vandalism and spam is to use
-a regular web server as reverse proxy. This page explains how to setup
-Apache on Debian to do this.
+The best way to protect the wiki against vandalism and spam is to use a regular
+web server as reverse proxy. This page explains how to setup Apache on Debian to
+do this.
 
 ## CONFIGURATION
 
-HTTPS is not part of the wiki. You probably want to configure this in
-your webserver. I guess you could use stunnel, too. If you're using
-Apache, you can use "mod_md" to manage your domain.
+HTTPS is not part of Oddmu. You probably want to configure this in your
+webserver. I guess you could use stunnel, too. If you're using Apache, you can
+use "mod_md" to manage your domain.
 
 In the example below, the site is configured in a file called
-"/etc/apache2/sites-available/500-transjovian.conf" and a link poins
-there from "/etc/apache2/sites-enabled". Create this link using
-_a2ensite_(1).
+"/etc/apache2/sites-available/500-transjovian.conf" and a link poins there from
+"/etc/apache2/sites-enabled". Create this link using _a2ensite_(1).
 
 ```
 MDomain transjovian.org
@@ -38,21 +36,22 @@ MDCertificateAgreement accepted
     ServerAdmin alex@alexschroeder.ch
     ServerName transjovian.org
     SSLEngine on
-    ProxyPassMatch ^/(search|(view|edit|save|add|append|upload|drop)/(.*))?$ http://localhost:8080/$1
+    ProxyPassMatch "^/((view|diff|edit|save|add|append|upload|drop|search)/(.*))?$" "http://localhost:8080/$1"
 </VirtualHost>
 ```
 
-First, it manages the domain, getting the necessary certificates. It
-redirects regular HTTP traffic from port 80 to port 443. It turns on
-the SSL engine for port 443. It proxies the requests for the wiki to
-port 8080.
+First, it manages the domain, getting the necessary certificates. It redirects
+regular HTTP traffic from port 80 to port 443. It turns on the SSL engine for
+port 443. It proxies the requests for Oddmu to port 8080. Importantly, it
+doesn't send _all_ the requests to Oddmu. This allows us to still host static
+files using the web server.
 
-Thus, this is what happens:
+This is what happens:
 
-* The user tells the browser to visit `transjovian.org`
-* The browser sends a request for `http://transjovian.org` (on port 80)
-* Apache redirects this to `https://transjovian.org/` by default (now on port 443)
-* This is proxied to `http://transjovian.org:8080/` (no encryption, on port 8080)
+- The user tells the browser to visit "transjovian.org"
+- The browser sends a request for "http://transjovian.org" (on port 80)
+- Apache redirects this to "https://transjovian.org/" by default (now on port 443)
+- This is proxied to "http://transjovian.org:8080/" (now on port 8080)
 
 Restart the server, gracefully:
 
@@ -60,41 +59,45 @@ Restart the server, gracefully:
 apachectl graceful
 ```
 
-To serve both HTTP and HTTPS, don't redirect from the first virtual
-host to the second – instead just proxy to the wiki like you did for
-the second virtual host: use a copy of the "ProxyPassMatch" directive
-instead of "RewriteEngine on" and "RewriteRule".
+To serve both HTTP and HTTPS, don't redirect from the first virtual host to the
+second – instead just proxy to the wiki like you did for the second virtual
+host: use a copy of the "ProxyPassMatch" directive instead of "RewriteEngine on"
+and "RewriteRule".
 
 ## Access
 
-Access control is not part of the wiki. By default, the wiki is
-editable by all. This is most likely not what you want unless you're
-running it stand-alone, unconnected to the Internet.
+Access control is not part of Oddmu. By default, the wiki is editable by all.
+This is most likely not what you want unless you're running it stand-alone,
+unconnected to the Internet – a person memex on your laptop, for example.
 
-Create a new password file called ".htpasswd" and add the user "alex":
+The following instructions create user accounts with passwords just for Oddmu.
+These users are not real users on the web server and don't have access to a
+shell, mail, or any other service.
+
+Create a new password file called ".htpasswd" and add the user "alex". The "-c"
+flag creates the file.
 
 ```
 cd /home/oddmu
 htpasswd -c .htpasswd alex
 ```
 
-To add more users, don't use the "-c" option or you will overwrite it!
-
-To add another user:
+To add more users, don't use the "-c" option or you will overwrite the existing
+file. To add another user, use no option at all.
 
 ```
 htpasswd .htpasswd berta
 ```
 
-To remove a user:
+To remove a user, use the "-D" option.
 
 ```
 htpasswd -D .htpasswd berta
 ```
 
-Modify your site configuration and protect the "/edit/", "/save/",
-"/add/", "/append/", "/upload/" and "/drop/" URLs with a password by
-adding the following to your "<VirtualHost \*:443>" section:
+Modify your site configuration and protect the "/edit/", "/save/", "/add/",
+"/append/", "/upload/" and "/drop/" URLs with a password by adding the following
+to your "<VirtualHost \*:443>" section:
 
 ```
 <LocationMatch "^/(edit|save|add|append|upload|drop)/">
@@ -107,10 +110,9 @@ adding the following to your "<VirtualHost \*:443>" section:
 
 ## Serve static files
 
-If you want to serve static files as well, add a document root to your
-webserver configuration. In this case, the document root is the
-directory where all the data files are. Apache will not serve files
-such as ".htpasswd".
+If you want to serve static files as well, add a document root to your webserver
+configuration. In this case, the document root is the directory where all the
+data files are. Apache does not serve files such as ".htpasswd".
 
 ```
 DocumentRoot /home/oddmu
@@ -119,26 +121,28 @@ DocumentRoot /home/oddmu
 </Directory>
 ```
 
-Make sure that none of the subdirectories look like the wiki paths
-"/view/", "/edit/", "/save/", "/add/", "/append/", "/upload/",
-"/drop/" or "/search". For example, create a file called "robots.txt"
-containing the following, telling all robots that they're not welcome.
+Make sure that none of the subdirectories look like the wiki paths "/view/",
+"/diff/", "/edit/", "/save/", "/add/", "/append/", "/upload/", "/drop/" or
+"/search/". For example, create a file called "robots.txt" containing the
+following, telling all robots that they're not welcome.
 
 ```
 User-agent: *
 Disallow: /
 ```
 
-You site now serves "/robots.txt" without interfering with the wiki,
-and without needing a wiki page.
+You site now serves "/robots.txt" without interfering with the wiki, and without
+needing a wiki page.
+
+Another option would be to create a CSS file and use it with a <link> element in
+all the templates instead of relying on the <style> element.
 
 ## Different logins for different access rights
 
-What if you have a site with various subdirectories and each
-subdirectory is for a different group of friends? You can set this up
-using your webserver. One way to do this is to require specific
-usernames (which must have a password in the password file mentioned
-above.
+What if you have a site with various subdirectories and each subdirectory is for
+a different group of friends? You can set this up using your webserver. One way
+to do this is to require specific usernames (which must have a password in the
+password file mentioned above.
 
 This requires a valid login by the user "alex" or "berta":
 
@@ -150,9 +154,8 @@ This requires a valid login by the user "alex" or "berta":
 
 ## Private wikis
 
-Based on the above, you can prevent people from _reading_ the wiki.
-The "LocationMatch" must cover the "/view/" URLs in order to protect
-*everything*.
+Based on the above, you can prevent people from _reading_ the wiki. The
+"LocationMatch" must cover all the URLs in order to protect everything.
 
 ```
 <Location />
@@ -165,12 +168,11 @@ The "LocationMatch" must cover the "/view/" URLs in order to protect
 
 ## Virtual hosting
 
-Virtual hosting in this context means that the program serves two
-different sites for two different domains from the same machine. Oddmu
-doesn't support that, but your webserver does. Therefore, start an
-Oddmu instance for every domain name, each listening on a different
-port. Then set up your web server such that ever domain acts as a
-reverse proxy to a different Oddmu instance.
+Virtual hosting in this context means that the program serves two different
+sites for two different domains from the same machine. Oddmu doesn't support
+that, but your webserver does. Therefore, start an Oddmu instance for every
+domain name, each listening on a different port. Then set up your web server
+such that ever domain acts as a reverse proxy to a different Oddmu instance.
 
 # SEE ALSO
 
@@ -188,6 +190,12 @@ https://httpd.apache.org/docs/current/mod/mod_proxy.html
 "Robot exclusion standard" on Wikipedia.
 https://en.wikipedia.org/wiki/Robot_exclusion_standard
 
+"<style>: The Style Information element"
+https://developer.mozilla.org/en-US/docs/Web/HTML/Element/style
+
+"<link>: The External Resource Link element"
+https://developer.mozilla.org/en-US/docs/Web/HTML/Element/link
+
 # AUTHORS
 
 Maintained by Alex Schroeder <alex@gnu.org>.

man/oddmu-html.1

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU-HTML" "1" "2023-09-22"
+.TH "ODDMU-HTML" "1" "2023-10-09"
 .PP
 .SH NAME
 .PP
@@ -17,16 +17,16 @@ oddmu-html - render Oddmu page HTML from the command-line
 .PP
 .SH DESCRIPTION
 .PP
-The "html" subcommand opens the Markdown file for the given page name
-(appending the ".\&md" extension) and prints the HTML to STDOUT without
-invoking the "view.\&html" template.\&
+The "html" subcommand opens the Markdown file for the given page name (appending
+the ".\&md" extension) and prints the HTML to STDOUT without invoking the
+"view.\&html" template.\&
 .PP
 .SH OPTIONS
 .PP
 \fB-view\fR
 .RS 4
-Use the "view.\&html" template to render the page.\& Without this,
-the HTML will lack html and body tags.\&
+Use the "view.\&html" template to render the page.\& Without this, the HTML
+lacks html and body tags.\&
 .PP
 .RE
 .SH EXAMPLE
@@ -41,8 +41,8 @@ oddmu html README
 .PP
 .SH ENVIRONMENT
 .PP
-The ODDMU_WEBFINGER environment variable has no effect in this
-situation.\& Fediverse accounts are not linked to their profile pages.\&
+The ODDMU_WEBFINGER environment variable has no effect in this situation.\&
+Fediverse accounts are not linked to their profile pages.\&
 .PP
 .SH SEE ALSO
 .PP

man/oddmu-html.1.txt

@@ -10,15 +10,15 @@ oddmu-html - render Oddmu page HTML from the command-line
 
 # DESCRIPTION
 
-The "html" subcommand opens the Markdown file for the given page name
-(appending the ".md" extension) and prints the HTML to STDOUT without
-invoking the "view.html" template.
+The "html" subcommand opens the Markdown file for the given page name (appending
+the ".md" extension) and prints the HTML to STDOUT without invoking the
+"view.html" template.
 
 # OPTIONS
 
 *-view*
-	Use the "view.html" template to render the page. Without this,
-	the HTML will lack html and body tags.
+	Use the "view.html" template to render the page. Without this, the HTML
+	lacks html and body tags.
 
 # EXAMPLE
 
@@ -30,8 +30,8 @@ oddmu html README
 
 # ENVIRONMENT
 
-The ODDMU_WEBFINGER environment variable has no effect in this
-situation. Fediverse accounts are not linked to their profile pages.
+The ODDMU_WEBFINGER environment variable has no effect in this situation.
+Fediverse accounts are not linked to their profile pages.
 
 # SEE ALSO
 

man/oddmu-missing.1

@@ -0,0 +1,57 @@
+.\" Generated by scdoc 1.11.2
+.\" Complete documentation for this program is not available as a GNU info page
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.nh
+.ad l
+.\" Begin generated content:
+.TH "ODDMU-MISSING" "1" "2023-11-05"
+.PP
+.SH NAME
+.PP
+oddmu-missing - list missing pages from the command-line
+.PP
+.SH SYNOPSIS
+.PP
+\fBoddmu missing\fR
+.PP
+.SH DESCRIPTION
+.PP
+The "missing" subcommand lists pages and their local links that are missing.\&
+.PP
+Any links that seem like they might point outside the wiki are ignored: links
+that start with a slash "/" and links that start with a known URL schema
+(currently: "http:", "https:", "ftp:", "mailto:", "gopher:", "gemini:",
+"finger:").\&
+.PP
+Notably, links that start with ".\&.\&/" are reported as missing.\&
+.PP
+.SH EXAMPLE
+.PP
+Looking for broken links:
+.PP
+.nf
+.RS 4
+oddmu missing
+.fi
+.RE
+.PP
+Result:
+.PP
+.nf
+.RS 4
+Page	Missing
+README	github\&.com/pemistahl/lingua-go
+.fi
+.RE
+.PP
+This shows how the README file had a link where the URL was missing the scheme
+"https://".\&
+.PP
+.SH SEE ALSO
+.PP
+\fIoddmu\fR(1), \fIoddmu-replace\fR(1), \fIoddmu-missing\fR(7)
+.PP
+.SH AUTHORS
+.PP
+Maintained by Alex Schroeder <alex@gnu.\&org>.\&

man/oddmu-missing.1.txt

@@ -0,0 +1,46 @@
+ODDMU-MISSING(1)
+
+# NAME
+
+oddmu-missing - list missing pages from the command-line
+
+# SYNOPSIS
+
+*oddmu missing*
+
+# DESCRIPTION
+
+The "missing" subcommand lists pages and their local links that are missing.
+
+Any links that seem like they might point outside the wiki are ignored: links
+that start with a slash "/" and links that start with a known URL schema
+(currently: "http:", "https:", "ftp:", "mailto:", "gopher:", "gemini:",
+"finger:").
+
+Notably, links that start with "../" are reported as missing.
+
+# EXAMPLE
+
+Looking for broken links:
+
+```
+oddmu missing
+```
+
+Result:
+
+```
+Page	Missing
+README	github.com/pemistahl/lingua-go
+```
+
+This shows how the README file had a link where the URL was missing the scheme
+"https://".
+
+# SEE ALSO
+
+_oddmu_(1), _oddmu-replace_(1), _oddmu-missing_(7)
+
+# AUTHORS
+
+Maintained by Alex Schroeder <alex@gnu.org>.

man/oddmu-notify.1

@@ -0,0 +1,68 @@
+.\" Generated by scdoc 1.11.2
+.\" Complete documentation for this program is not available as a GNU info page
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.nh
+.ad l
+.\" Begin generated content:
+.TH "ODDMU-NOTIFY" "1" "2023-11-06"
+.PP
+.SH NAME
+.PP
+oddmu-notify - add links to changes.\&md, index.\&md, and hashtag pages
+.PP
+.SH SYNOPSIS
+.PP
+\fBoddmu notify\fR \fIpage names.\&.\&.\&\fR 
+.PP
+.SH DESCRIPTION
+.PP
+The "notify" subcommand takes all the page names provided (without the ".\&md"
+extension) and adds links to it from other pages.\&
+.PP
+A new link is added to the \fBchanges\fR page if it doesn'\&t exist.\& The current date
+of the machine Oddmu is running on is used as the heading.\& If the requested link
+already exists on the changes page, it is moved up to the current date.\& If that
+leaves an old date without any links, that date heading is removed.\&
+.PP
+A page whose name starts with an ISO date (YYYY-MM-DD, e.\&g.\& "2023-10-28") is
+called a \fBblog\fR page.\&
+.PP
+A link is created from the \fBindex\fR page to blog pages if and only if the blog
+pages are from the current year.\& The idea is that the front page contains a lot
+of links to blog posts but eventually the blog post links are moved onto archive
+pages (one per year, for example), or simply deleted.\& As when editing older
+pages, links to those pages should not get added to the index as if those older
+pages were new again.\& A link on the changes page is enough.\&
+.PP
+For every \fBhashtag\fR used on the pages named, another link might be created.\& If a
+page named like the hashtag exists, a backlink is added to it.\& A hashtag
+consists of a number sign ('\&#'\&) followed by Unicode letters, numbers or the
+underscore ('\&_'\&).\& Thus, a hashtag ends with punctuation or whitespace.\&
+.PP
+If a link already exists but it'\&s title is no longer correct, it is updated.\&
+.PP
+New links added for blog pages are added at the top of the first unnumbered list
+using the asterisk ('\&*'\&).\& If no such list exists, a new one is started at the
+bottom of the page.\& This allows you to have a different unnumbered list further
+up on the page, as long as it uses the minus for items ('\&-'\&).\&
+.PP
+.SH EXAMPLE
+.PP
+After writing the file "2023-11-05-climate.\&md" containing the hashtag
+"#Climate", add links to it from "index.\&md", "changes.\&md", and "Climate.\&md" (if
+it exists):
+.PP
+.nf
+.RS 4
+oddmu notify 2023-11-05-climate
+.fi
+.RE
+.PP
+.SH SEE ALSO
+.PP
+\fIoddmu\fR(1)
+.PP
+.SH AUTHORS
+.PP
+Maintained by Alex Schroeder <alex@gnu.\&org>.\&

man/oddmu-notify.1.txt

@@ -0,0 +1,59 @@
+ODDMU-NOTIFY(1)
+
+# NAME
+
+oddmu-notify - add links to changes.md, index.md, and hashtag pages
+
+# SYNOPSIS
+
+*oddmu notify* _page names..._ 
+
+# DESCRIPTION
+
+The "notify" subcommand takes all the page names provided (without the ".md"
+extension) and adds links to it from other pages.
+
+A new link is added to the *changes* page if it doesn't exist. The current date
+of the machine Oddmu is running on is used as the heading. If the requested link
+already exists on the changes page, it is moved up to the current date. If that
+leaves an old date without any links, that date heading is removed.
+
+A page whose name starts with an ISO date (YYYY-MM-DD, e.g. "2023-10-28") is
+called a *blog* page.
+
+A link is created from the *index* page to blog pages if and only if the blog
+pages are from the current year. The idea is that the front page contains a lot
+of links to blog posts but eventually the blog post links are moved onto archive
+pages (one per year, for example), or simply deleted. As when editing older
+pages, links to those pages should not get added to the index as if those older
+pages were new again. A link on the changes page is enough.
+
+For every *hashtag* used on the pages named, another link might be created. If a
+page named like the hashtag exists, a backlink is added to it. A hashtag
+consists of a number sign ('#') followed by Unicode letters, numbers or the
+underscore ('\_'). Thus, a hashtag ends with punctuation or whitespace.
+
+If a link already exists but it's title is no longer correct, it is updated.
+
+New links added for blog pages are added at the top of the first unnumbered list
+using the asterisk ('\*'). If no such list exists, a new one is started at the
+bottom of the page. This allows you to have a different unnumbered list further
+up on the page, as long as it uses the minus for items ('-').
+
+# EXAMPLE
+
+After writing the file "2023-11-05-climate.md" containing the hashtag
+"#Climate", add links to it from "index.md", "changes.md", and "Climate.md" (if
+it exists):
+
+```
+oddmu notify 2023-11-05-climate
+```
+
+# SEE ALSO
+
+_oddmu_(1)
+
+# AUTHORS
+
+Maintained by Alex Schroeder <alex@gnu.org>.

man/oddmu-replace.1

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU-REPLACE" "1" "2023-09-22"
+.TH "ODDMU-REPLACE" "1" "2023-11-24"
 .PP
 .SH NAME
 .PP
@@ -13,30 +13,36 @@ oddmu-replace - replace text in Oddmu pages from the command-line
 .PP
 .SH SYNOPSIS
 .PP
-\fBoddmu replace\fR [-confirm] \fIregexp\fR \fIreplacement\fR
+\fBoddmu replace\fR [-confirm] [-regexp] \fIterm\fR \fIreplacement\fR
 .PP
 .SH DESCRIPTION
 .PP
-The "replace" subcommand replaces the Markdown files in the current
-directory (!\&), returning the replace result as a Markdown-formatted
-list.\&
+The "replace" subcommand does a search and replace on all the Markdown files in
+the current directory and its subdirectories.\&
 .PP
 .SH OPTIONS
 .PP
 \fB-confirm\fR
 .RS 4
-By default, the replacement doesn'\&t save the changes made.\&
-Instead, a unified diff is produced and printed.\& Given this
-option, the changed Markdown files are saved to disk.\&
+By default, the replacement doesn'\&t save the changes made.\& Instead, a
+unified diff is produced and printed.\& Given this option, the changed
+Markdown files are saved to disk.\&
+.PP
+.RE
+\fB-regexp\fR
+.RS 4
+By default, the term to be replaced is just a string.\& With this flag,
+the term is a regular expression and the replacement can contain
+backreferences ($1, $2, $3, etc.\&) to capture groups.\&
 .PP
 .RE
 .SH EXAMPLE
 .PP
-Replace for "oddmu" in the Markdown files of the current directory:
+Replace "Oddmu" in the Markdown files of the current directory:
 .PP
 .nf
 .RS 4
-oddmu replace oddmu
+oddmu replace Oddmu Oddµ
 .fi
 .RE
 .PP
@@ -44,18 +50,51 @@ Result:
 .PP
 .nf
 .RS 4
-Replace oddmu: 1 result
-* [Oddµ: A minimal wiki](README) (5)
+--- README\&.md~
++++ README\&.md
+
+(diff omitted)
+
+1 file would be changed\&.
+This is a dry run\&. Use -confirm to make it happen\&.
 .fi
 .RE
 .PP
 .SH NOTES
 .PP
-This is the equivalent of using \fIsed\fR(1) with the --quiet,
---regexp-extended, --in-place=~ and --expression command with the s
-command "s/regexp/replacement/g" except that it prints a unified diff
-per default instead of making any changes and the regexp rules differ
-slightly.\&
+This is the equivalent of using \fIsed\fR(1) with the --quiet, --regexp-extended,
+--in-place=~ and --expression command with the s command
+"s/regexp/replacement/g" except that it prints a unified diff per default
+instead of making any changes and the regexp rules differ slightly.\&
+.PP
+The search is case-sensitive.\& To make it case-insensitive, search for a regular
+expression that sets the case-insensitive flag, e.\&g.\& "(?\&i)oddmu".\&
+.PP
+.SH SECURITY
+.PP
+Consider creating a backup before doing replacements!\&
+.PP
+The following Bash script creates a copy of the current directory using hard
+links.\& If you'\&re in a directory called "wiki", it creates a sibling directory
+called "wiki-2023-11-24" (using the current date) full of links.\& This takes
+little space and time.\& It works as a backup as long as you don'\&t use an
+application that edits files in place.\& Most programs overwrite old files by
+creating new files with the same name, so you should be safe.\&
+.PP
+.nf
+.RS 4
+#!/usr/bin/bash
+d=$(basename $(pwd))
+t=$(date --iso-8601)
+echo Creating a snapshot of $d in \&.\&./$d-$t
+rsync --link-dest "\&.\&./$d" --archive \&. "\&.\&./$d-$t/"
+.fi
+.RE
+.PP
+The above wouldn'\&t work for database files, for example.\& There, the database
+changes the file in place thus the file is changed in the backup directory as
+well.\& For Oddmu and the usual text editors, it works.\& If you use Emacs, don'\&t
+set \fIbackup-by-copying\fR, \fIbackup-by-copying-when-linked\fR and related variables.\&
 .PP
 .SH SEE ALSO
 .PP

man/oddmu-replace.1.txt

@@ -6,43 +6,78 @@ oddmu-replace - replace text in Oddmu pages from the command-line
 
 # SYNOPSIS
 
-*oddmu replace* [-confirm] _regexp_ _replacement_
+*oddmu replace* [-confirm] [-regexp] _term_ _replacement_
 
 # DESCRIPTION
 
-The "replace" subcommand replaces the Markdown files in the current
-directory (!), returning the replace result as a Markdown-formatted
-list.
+The "replace" subcommand does a search and replace on all the Markdown files in
+the current directory and its subdirectories.
 
 # OPTIONS
 
 *-confirm*
-	By default, the replacement doesn't save the changes made.
-	Instead, a unified diff is produced and printed. Given this
-	option, the changed Markdown files are saved to disk.
+	By default, the replacement doesn't save the changes made. Instead, a
+	unified diff is produced and printed. Given this option, the changed
+	Markdown files are saved to disk.
+
+*-regexp*
+	By default, the term to be replaced is just a string. With this flag,
+	the term is a regular expression and the replacement can contain
+	backreferences ($1, $2, $3, etc.) to capture groups.
 
 # EXAMPLE
 
-Replace for "oddmu" in the Markdown files of the current directory:
+Replace "Oddmu" in the Markdown files of the current directory:
 
 ```
-oddmu replace oddmu
+oddmu replace Oddmu Oddµ
 ```
 
 Result:
 
 ```
-Replace oddmu: 1 result
-* [Oddµ: A minimal wiki](README) (5)
+--- README.md~
++++ README.md
+
+(diff omitted)
+
+1 file would be changed.
+This is a dry run. Use -confirm to make it happen.
 ```
 
 # NOTES
 
-This is the equivalent of using _sed_(1) with the --quiet,
-\--regexp-extended, --in-place=~ and --expression command with the s
-command "s/regexp/replacement/g" except that it prints a unified diff
-per default instead of making any changes and the regexp rules differ
-slightly.
+This is the equivalent of using _sed_(1) with the --quiet, --regexp-extended,
+\--in-place=~ and --expression command with the s command
+"s/regexp/replacement/g" except that it prints a unified diff per default
+instead of making any changes and the regexp rules differ slightly.
+
+The search is case-sensitive. To make it case-insensitive, search for a regular
+expression that sets the case-insensitive flag, e.g. "(?i)oddmu".
+
+# SECURITY
+
+Consider creating a backup before doing replacements!
+
+The following Bash script creates a copy of the current directory using hard
+links. If you're in a directory called "wiki", it creates a sibling directory
+called "wiki-2023-11-24" (using the current date) full of links. This takes
+little space and time. It works as a backup as long as you don't use an
+application that edits files in place. Most programs overwrite old files by
+creating new files with the same name, so you should be safe.
+
+```
+#!/usr/bin/bash
+d=$(basename $(pwd))
+t=$(date --iso-8601)
+echo Creating a snapshot of $d in ../$d-$t
+rsync --link-dest "../$d" --archive . "../$d-$t/"
+```
+
+The above wouldn't work for database files, for example. There, the database
+changes the file in place thus the file is changed in the backup directory as
+well. For Oddmu and the usual text editors, it works. If you use Emacs, don't
+set _backup-by-copying_, _backup-by-copying-when-linked_ and related variables.
 
 # SEE ALSO
 

man/oddmu-search.1

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU-SEARCH" "1" "2023-09-19"
+.TH "ODDMU-SEARCH" "1" "2023-10-10"
 .PP
 .SH NAME
 .PP
@@ -13,24 +13,29 @@ oddmu-search - search the Oddmu pages from the command-line
 .PP
 .SH SYNOPSIS
 .PP
-\fBoddmu search\fR [-page \fIn\fR] \fIterms.\&.\&.\&\fR
+\fBoddmu search\fR [-extract] [-page \fIn\fR] \fIterms.\&.\&.\&\fR
 .PP
 .SH DESCRIPTION
 .PP
 The "search" subcommand searches the Markdown files in the current
-directory (!\&), returning the search result as a Markdown-formatted
-list.\&
+directory.\&
 .PP
-The use of a trigram index makes it possible to find substrings and
-for the word order not to matter, but it also makes the search results
-a bit harder to understand.\& See \fIoddmu-search\fR(7) for more.\&
+Be default, this returns a Markdown-formatted list suitable for pasting into
+Oddmu pages.\&
+.PP
+See \fIoddmu-search\fR(7) for more information of how pages are searched, sorted and
+scored.\&
 .PP
 .SH OPTIONS
 .PP
+\fB-extract\fR
+.RS 4
+Print search extracts for interactive use from the command-line.\&
+.RE
 \fB-page\fR \fIn\fR
 .RS 4
-Search results are paginated and by default only the first
-page is shown.\& This option allows you to view other pages.\&
+Search results are paginated and by default only the first page is
+shown.\& This option allows you to view other pages.\&
 .PP
 .RE
 .SH EXAMPLE

man/oddmu-search.1.txt

@@ -6,23 +6,26 @@ oddmu-search - search the Oddmu pages from the command-line
 
 # SYNOPSIS
 
-*oddmu search* [-page _n_] _terms..._
+*oddmu search* [-extract] [-page _n_] _terms..._
 
 # DESCRIPTION
 
 The "search" subcommand searches the Markdown files in the current
-directory (!), returning the search result as a Markdown-formatted
-list.
+directory.
 
-The use of a trigram index makes it possible to find substrings and
-for the word order not to matter, but it also makes the search results
-a bit harder to understand. See _oddmu-search_(7) for more.
+Be default, this returns a Markdown-formatted list suitable for pasting into
+Oddmu pages.
+
+See _oddmu-search_(7) for more information of how pages are searched, sorted and
+scored.
 
 # OPTIONS
 
+*-extract*
+	Print search extracts for interactive use from the command-line.
 *-page* _n_
-	Search results are paginated and by default only the first
-	page is shown. This option allows you to view other pages.
+	Search results are paginated and by default only the first page is
+	shown. This option allows you to view other pages.
 
 # EXAMPLE
 

man/oddmu-search.7

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU-SEARCH" "7" "2023-09-18"
+.TH "ODDMU-SEARCH" "7" "2023-10-28"
 .PP
 .SH NAME
 .PP
@@ -17,23 +17,60 @@ oddmu-search - understanding the Oddmu search engine
 .PP
 .SH DESCRIPTION
 .PP
-The index indexes trigrams.\& Each group of three characters is a
-trigram.\& A document with content "This is a test" is turned to lower
-case and indexed under the trigrams "thi", "his", "is ", "s i", " is",
-"is ", "s a", " a ", "a t", " te", "tes", "est".\&
+The wiki keeps an index of all the hash tags and page titles in memory.\& Using
+hashtags and predicates in your queries speeds them up because fewer files are
+opened.\&
 .PP
-Each query is split into words and then processed the same way.\& A
-query with the words "this test" is turned to lower case and produces
-the trigrams "thi", "his", "tes", "est".\& This means that the word
-order is not considered when searching for documents.\&
+A hashtag starts with a number sign ('\&#'\&) and contains numbers, letters, and the
+underscore ('\&_'\&).\&
 .PP
-This also means that there is no stemming.\& Searching for "testing"
-won'\&t find "This is a test" because there are no matches for the
-trigrams "sti", "tin", "ing".\&
+Example: #old_school random encounter
 .PP
-These trigrams are looked up in the index, resulting in the list of
-documents.\& Each document found is then scored.\& Each of the following
-increases the score by one point:
+The title predicate filters for pages where the term is contained in the page
+title.\&
+.PP
+Example: title:geo title:cache zürich
+.PP
+The blog predicate filters for pages where the page name begins with an ISO date
+like "2023-09-26" if true, or doesn'\&t begin with an ISO date if false.\&
+.PP
+Example: blog:false fountain
+.PP
+The sorting of all the pages does not depend on the number of matches or any
+kind of score because computing the score is expensive as this requires the page
+to be loaded from disk.\& Therefore, results are sorted by title:
+.PP
+.PD 0
+.IP \(bu 4
+If a page title matches the query string exactly, it gets sorted first.\&
+.IP \(bu 4
+If the page title contains the query string, it gets sorted next.\&
+.IP \(bu 4
+If the page name starts with a number, it is sorted descending.\&
+.IP \(bu 4
+All other pages follow, sorted ascending.\&
+.PD
+.PP
+The effect is that first, the pages with matches in the page title are shown,
+and then all the others.\& Within these two groups, the most recent blog posts are
+shown first.\& This assumes that blog pages start with an ISO date like
+"2023-09-16".\&
+.PP
+When searching for a hashtag, a page name (not the title!\&) matching the hashtag
+exactly (without the leading '\&#'\&) is listed first, even if it doesn'\&t contain
+the hashtag.\& It is assumed that this page offers some kind of introduction to
+people searching for the hashtag.\&
+.PP
+Example: When people click on the hashtag "#Oddµ" and a page named "Oddµ" exists
+(in other words, the file "Oddµ.\&md" exists), it is prepended to the results even
+if it doesn'\&t have the hashtag "#Oddµ" and even if it has a title of "Oddµ, a
+minimal wiki" (which wouldn'\&t be an exact match).\&
+.PP
+The score and highlighting of snippets is used to help visitors decide which
+links to click.\&
+.PP
+Each document found is scored.\& Each of the following increases the score by one
+point:
 .PP
 .PD 0
 .IP \(bu 4
@@ -48,37 +85,9 @@ a word matches at the end of a word
 a word matches as a whole word
 .PD
 .PP
-A document with content "This is a test" when searched with the phrase
-"this test" therefore gets a score of 8: the entire phrase does not
-match but each word gets four points.\&
-.PP
-Trigrams are sometimes strange: In a text containing the words "main"
-and "rail", a search for "mail" returns a match because the trigrams
-"mai" and "ail" are found.\& In this situation, the result has a score
-of 0.\&
-.PP
-The sorting of all the pages, however, does not depend on scoring!\&
-Computing the score is expensive because the page must be loaded from
-disk.\& Therefore, results are sorted by title:
-.PP
-.PD 0
-.IP \(bu 4
-If the page title contains the query string, it gets sorted first.\&
-.IP \(bu 4
-If the page name (the filename!\&) begins with a number, it is sorted
-descending.\&
-.IP \(bu 4
-All other pages follow, sorted ascending.\&
-.PD
-.PP
-The effect is that first, the pages with matches in the page title are
-shown, and then all the others.\& Within these two groups, the most
-recent blog posts are shown first.\& This assumes that blog pages start
-with an ISO date like "2023-09-16".\&
-.PP
-The score and highlighting of snippets is used to help visitors decide
-which links to click.\& A score of 0 indicates that all the trigrams
-were found but \fIno exact matches\fR for any of the terms.\&
+A document with content "This is a test" when searched with the phrase "this
+test" therefore gets a score of 8: the entire phrase does not match but each
+word gets four points.\&
 .PP
 .SH SEE ALSO
 .PP

man/oddmu-search.7.txt

@@ -10,23 +10,54 @@ oddmu-search - understanding the Oddmu search engine
 
 # DESCRIPTION
 
-The index indexes trigrams. Each group of three characters is a
-trigram. A document with content "This is a test" is turned to lower
-case and indexed under the trigrams "thi", "his", "is ", "s i", " is",
-"is ", "s a", " a ", "a t", " te", "tes", "est".
+The wiki keeps an index of all the hash tags and page titles in memory. Using
+hashtags and predicates in your queries speeds them up because fewer files are
+opened.
 
-Each query is split into words and then processed the same way. A
-query with the words "this test" is turned to lower case and produces
-the trigrams "thi", "his", "tes", "est". This means that the word
-order is not considered when searching for documents.
+A hashtag starts with a number sign ('#') and contains numbers, letters, and the
+underscore ('\_').
 
-This also means that there is no stemming. Searching for "testing"
-won't find "This is a test" because there are no matches for the
-trigrams "sti", "tin", "ing".
+Example: #old_school random encounter
 
-These trigrams are looked up in the index, resulting in the list of
-documents. Each document found is then scored. Each of the following
-increases the score by one point:
+The title predicate filters for pages where the term is contained in the page
+title.
+
+Example: title:geo title:cache zürich
+
+The blog predicate filters for pages where the page name begins with an ISO date
+like "2023-09-26" if true, or doesn't begin with an ISO date if false.
+
+Example: blog:false fountain
+
+The sorting of all the pages does not depend on the number of matches or any
+kind of score because computing the score is expensive as this requires the page
+to be loaded from disk. Therefore, results are sorted by title:
+
+- If a page title matches the query string exactly, it gets sorted first.
+- If the page title contains the query string, it gets sorted next.
+- If the page name starts with a number, it is sorted descending.
+- All other pages follow, sorted ascending.
+
+The effect is that first, the pages with matches in the page title are shown,
+and then all the others. Within these two groups, the most recent blog posts are
+shown first. This assumes that blog pages start with an ISO date like
+"2023-09-16".
+
+When searching for a hashtag, a page name (not the title!) matching the hashtag
+exactly (without the leading '#') is listed first, even if it doesn't contain
+the hashtag. It is assumed that this page offers some kind of introduction to
+people searching for the hashtag.
+
+Example: When people click on the hashtag "#Oddµ" and a page named "Oddµ" exists
+(in other words, the file "Oddµ.md" exists), it is prepended to the results even
+if it doesn't have the hashtag "#Oddµ" and even if it has a title of "Oddµ, a
+minimal wiki" (which wouldn't be an exact match).
+
+The score and highlighting of snippets is used to help visitors decide which
+links to click.
+
+Each document found is scored. Each of the following increases the score by one
+point:
 
 - the entire phrase matches
 - a word matches
@@ -34,32 +65,9 @@ increases the score by one point:
 - a word matches at the end of a word
 - a word matches as a whole word
 
-A document with content "This is a test" when searched with the phrase
-"this test" therefore gets a score of 8: the entire phrase does not
-match but each word gets four points.
-
-Trigrams are sometimes strange: In a text containing the words "main"
-and "rail", a search for "mail" returns a match because the trigrams
-"mai" and "ail" are found. In this situation, the result has a score
-of 0.
-
-The sorting of all the pages, however, does not depend on scoring!
-Computing the score is expensive because the page must be loaded from
-disk. Therefore, results are sorted by title:
-
-- If the page title contains the query string, it gets sorted first.
-- If the page name (the filename!) begins with a number, it is sorted
-  descending.
-- All other pages follow, sorted ascending.
-
-The effect is that first, the pages with matches in the page title are
-shown, and then all the others. Within these two groups, the most
-recent blog posts are shown first. This assumes that blog pages start
-with an ISO date like "2023-09-16".
-
-The score and highlighting of snippets is used to help visitors decide
-which links to click. A score of 0 indicates that all the trigrams
-were found but _no exact matches_ for any of the terms.
+A document with content "This is a test" when searched with the phrase "this
+test" therefore gets a score of 8: the entire phrase does not match but each
+word gets four points.
 
 # SEE ALSO
 

man/oddmu-static.1

@@ -0,0 +1,62 @@
+.\" Generated by scdoc 1.11.2
+.\" Complete documentation for this program is not available as a GNU info page
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.nh
+.ad l
+.\" Begin generated content:
+.TH "ODDMU-STATIC" "1" "2023-11-05"
+.PP
+.SH NAME
+.PP
+oddmu-static - create a static copy of the site
+.PP
+.SH SYNOPSIS
+.PP
+\fBoddmu static\fR \fIdir-name\fR
+.PP
+.SH DESCRIPTION
+.PP
+The "static" subcommand generates a static copy of the pages in the current
+directory and saves them in the given target directory.\& The target directory
+must not exist to unser no existing files are clobbered.\&
+.PP
+All pages (files with the ".\&md" extension) are turned into HTML files (with the
+".\&html" extension) using the "static.\&html" template.\& Links pointing to existing
+pages get ".\&html" appended.\&
+.PP
+Hidden files and directories (starting with a ".\&") and backup files (ending with
+a "~") are skipped.\&
+.PP
+All other files are \fIlinked\fR into the same directory.\&
+.PP
+.SH EXAMPLE
+.PP
+Generate a static copy of the site:
+.PP
+.nf
+.RS 4
+oddmu static \&.\&./archive
+.fi
+.RE
+.PP
+.SH LIMITATIONS
+.PP
+Links from files to pages do not get ".\&html" appended.\& This affects existing
+HTML or XML files including SVG files.\&
+.PP
+Links to absolute URLs (starting with "/") are not changed at all.\& It is up to
+you to migrate static folders and applications.\&
+.PP
+.SH ENVIRONMENT
+.PP
+The ODDMU_WEBFINGER environment variable has no effect in this situation.\&
+Fediverse accounts are not linked to their profile pages.\&
+.PP
+.SH SEE ALSO
+.PP
+\fIoddmu\fR(1), \fIoddmu-templates\fR(5)
+.PP
+.SH AUTHORS
+.PP
+Maintained by Alex Schroeder <alex@gnu.\&org>.\&

man/oddmu-static.1.txt

@@ -0,0 +1,53 @@
+ODDMU-STATIC(1)
+
+# NAME
+
+oddmu-static - create a static copy of the site
+
+# SYNOPSIS
+
+*oddmu static* _dir-name_
+
+# DESCRIPTION
+
+The "static" subcommand generates a static copy of the pages in the current
+directory and saves them in the given target directory. The target directory
+must not exist to unser no existing files are clobbered.
+
+All pages (files with the ".md" extension) are turned into HTML files (with the
+".html" extension) using the "static.html" template. Links pointing to existing
+pages get ".html" appended.
+
+Hidden files and directories (starting with a ".") and backup files (ending with
+a "~") are skipped.
+
+All other files are _linked_ into the same directory.
+
+# EXAMPLE
+
+Generate a static copy of the site:
+
+```
+oddmu static ../archive
+```
+
+# LIMITATIONS
+
+Links from files to pages do not get ".html" appended. This affects existing
+HTML or XML files including SVG files.
+
+Links to absolute URLs (starting with "/") are not changed at all. It is up to
+you to migrate static folders and applications.
+
+# ENVIRONMENT
+
+The ODDMU_WEBFINGER environment variable has no effect in this situation.
+Fediverse accounts are not linked to their profile pages.
+
+# SEE ALSO
+
+_oddmu_(1), _oddmu-templates_(5)
+
+# AUTHORS
+
+Maintained by Alex Schroeder <alex@gnu.org>.

man/oddmu-templates.5

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU-TEMPLATES" "5" "2023-09-22" "File Formats Manual"
+.TH "ODDMU-TEMPLATES" "5" "2023-10-29" "File Formats Manual"
 .PP
 .SH NAME
 .PP
@@ -15,38 +15,49 @@ oddmu-templates - how to write the templates
 .PP
 The templates can refer to the following properties of a page:
 .PP
-\fI{{.\&Title}}\fR is the page title.\& If the page doesn'\&t provide its own
-title, the page name is used.\&
+\fI{{.\&Title}}\fR is the page title.\& If the page doesn'\&t provide its own title, the
+page name is used.\&
 .PP
-\fI{{.\&Name}}\fR is the page name, escaped for use in URLs.\& More
-specifically, it is URI escaped except for the slashes.\& The page name
-doesn'\&t include the \fI.\&md\fR extension.\&
+\fI{{.\&Name}}\fR is the page name, escaped for use in URLs.\& More specifically, it is
+percent-escaped except for the slashes.\& The page name doesn'\&t include the \fI.\&md\fR
+extension.\&
 .PP
-For the \fIview.\&html\fR template:
+\fI{{.\&Dir}}\fR is the page directory, percent-escaped except for the slashes.\&
+.PP
+\fI{{.\&Today}}\fR is the current date, in ISO format.\& This is useful for "new page"
+like links or forms (see \fBEXAMPLE\fR below).\&
+.PP
+For the \fIview.\&html\fR and \fIstatic.\&html\fR template:
 .PP
 \fI{{.\&Html}}\fR is the rendered Markdown, as HTML.\&
 .PP
 \fI{{.\&Hashtags}}\fR is an array of strings.\&
 .PP
+For the \fIdiff.\&html\fR template:
+.PP
+\fI{{.\&Diff}}\fR is the diff for this page.\& This is only computed on demand so it can
+be used in other templates, too.\& It probably doesn'\&t make much sense to do so,
+however.\&
+.PP
 For the \fIedit.\&html\fR template:
 .PP
-\fI{{printf "%s" .\&Body}}\fR is the Markdown, as a string (the data itself
-is a byte array and that'\&s why we need to call \fIprintf\fR).\&
+\fI{{printf "%s" .\&Body}}\fR is the Markdown, as a string (the data itself is a byte
+array and that'\&s why we need to call \fIprintf\fR).\&
 .PP
 For the \fIsearch.\&html\fR template only:
 .PP
-\fI{{.\&Previous}}\fR, \fI{{.\&Page}}\fR, \fI{{.\&Next}}\fR and \fI{{.\&Last}}\fR are the
-previous, current, next and last page number in the results since
-doing arithmetics in templates is hard.\& The first page number is 1.\&
+\fI{{.\&Previous}}\fR, \fI{{.\&Page}}\fR and \fI{{.\&Next}}\fR are the previous, current and next
+page number in the results since doing arithmetics in templates is hard.\& The
+first page number is 1.\& The last page is expensive to dermine and so that isn'\&t
+done.\&
 .PP
 \fI{{.\&More}}\fR indicates if there are any more search results.\&
 .PP
 \fI{{.\&Results}}\fR indicates if there were any search results at all.\&
 .PP
-\fI{{.\&Items}}\fR is an array of pages, each containing a search result.\& A
-search result is a page (with the properties seen above).\& Thus, to
-refer to them, you need to use a \fI{{range .\&Items}}\fR … \fI{{end}}\fR
-construct.\&
+\fI{{.\&Items}}\fR is an array of pages, each containing a search result.\& A search
+result is a page (with the properties seen above).\& Thus, to refer to them, you
+need to use a \fI{{range .\&Items}}\fR … \fI{{end}}\fR construct.\&
 .PP
 For items in the search result:
 .PP
@@ -60,8 +71,8 @@ For the \fIfeed.\&html\fR template:
 .PP
 \fI{{.\&Title}}\fR is the title of the underlying main page.\&
 .PP
-\fI{{.\&Date}}\fR is the date of the last update to the underlying main page,
-in RFC 822 format.\&
+\fI{{.\&Date}}\fR is the date of the last update to the underlying main page, in RFC
+822 format.\&
 .PP
 \fI{{.\&Items}}\fR is an array of feed items.\&
 .PP
@@ -71,19 +82,17 @@ For items in the feed:
 .PP
 \fI{{.\&Title}}\fR is the title of the page.\&
 .PP
-\fI{{.\&Html}}\fR is the rendered Markdown, as HTML.\&
+\fI{{.\&Html}}\fR is the rendered Markdown, as escaped (!\&) HTML.\&
 .PP
 \fI{{.\&Hashtags}}\fR is an array of strings.\&
 .PP
-\fI{{.\&Date}}\fR, the date of the last update to this page, in RFC 822
-format.\&
+\fI{{.\&Date}}\fR, the date of the last update to this page, in RFC 822 format.\&
 .PP
 The \fIupload.\&html\fR template cannot refer to anything.\&
 .PP
-When calling the \fIsave\fR and \fIappend\fR action, the page name is taken
-from the URL path and the page content is taken from the \fIbody\fR form
-parameter.\& To illustrate, here'\&s how to edit the "welcome" page using
-\fIcurl\fR:
+When calling the \fIsave\fR and \fIappend\fR action, the page name is taken from the URL
+path and the page content is taken from the \fIbody\fR form parameter.\& To
+illustrate, here'\&s how to edit the "welcome" page using \fIcurl\fR:
 .PP
 .nf
 .RS 4
@@ -92,42 +101,76 @@ curl --form body="Did you bring a towel?"
 .fi
 .RE
 .PP
-When calling the \fIsearch\fR action, the query is taken from the URL
-parameter \fIq\fR.\&
+When calling the \fIsearch\fR action, the query is taken from the URL parameter \fIq\fR.\&
 .PP
 .nf
 .RS 4
-curl http://localhost:8080/search?q=towel
+curl http://localhost:8080/search/?q=towel
 .fi
 .RE
 .PP
 .SS Non-English hyphenation
 .PP
-Automatic hyphenation by the browser requires two things: The style
-sheet must indicate "hyphen: auto" for an HTML element such as "body",
-and that element must have a "lang" set (usually a two letter language
-code such as "de" for German).\&
+Automatic hyphenation by the browser requires two things: The style sheet must
+indicate "hyphen: auto" for an HTML element such as "body", and that element
+must have a "lang" set (usually a two letter language code such as "de" for
+German).\&
 .PP
-Oddmu attempts to detect the correct language for each page.\& It
-assumes that languages are not mixed on the same page.\& If you know
-that you'\&re only going to use a small number of languages – or just a
-single language!\& – you can set the environment variable
-ODDMU_LANGUAGES to a comma-separated list of ISO 639-1 codes, e.\&g.\&
-"en" or "en,de,fr,pt".\&
+Oddmu attempts to detect the correct language for each page.\& It assumes that
+languages are not mixed on the same page.\& If you know that you'\&re only going to
+use a small number of languages – or just a single language!\& – you can set the
+environment variable ODDMU_LANGUAGES to a comma-separated list of ISO 639-1
+codes, e.\&g.\& "en" or "en,de,fr,pt".\&
 .PP
-"view.\&html" is used the template to render a single page and so the
-language detected is added to the "html" element.\&
+"view.\&html" is used the template to render a single page and so the language
+detected is added to the "html" element.\&
 .PP
-"search.\&html" is the template used to render search results and so
-"en" is used for the "html" element and the language detected for
-every page in the search result is added to the "article" element for
-each snippet.\&
+"search.\&html" is the template used to render search results and so "en" is used
+for the "html" element and the language detected for every page in the search
+result is added to the "article" element for each snippet.\&
 .PP
-"edit.\&html" and "add.\&html" are the templates used to edit a page and
-at that point, the language isn'\&t known, so "en" is used for the
-"html" element and no language is used for the "textarea" element.\&
+"edit.\&html" and "add.\&html" are the templates used to edit a page and at that
+point, the language isn'\&t known, so "en" is used for the "html" element and no
+language is used for the "textarea" element.\&
 .PP
-SEE ALSO
+.SH EXAMPLE
+.PP
+The following link in a template takes people to today'\&s page.\& If no such page
+exists, they are redirected to the edit form where it can be created.\&
+.PP
+.nf
+.RS 4
+<a href="/view/{{\&.Today}}" accesskey="t">Today</a>
+.fi
+.RE
+.PP
+The following form allows people to edit the suggested page name.\&
+.PP
+.nf
+.RS 4
+<form role="new" action="/edit/{{\&.Dir}}" method="GET">
+  <label for="id">New page:</label>
+  <input id="id" type="text" spellcheck="false" name="id"
+	  accesskey="g" value="{{\&.Today}}" required>
+  <button>Edit</button>
+</form>
+.fi
+.RE
+.PP
+.SH NOTES
+.PP
+The template are always used as-is, irrespective of the current directory.\&
+Therefore, a link to a specific page must be \fIabsolute\fR or it'\&ll point to a
+different page depending on the current directory.\&
+.PP
+Consider the link to "/view/index".\& No matter what page a visitor is looking,
+this takes visitors to the top "index" page.\& If the link points to "index"
+instead, it takes a visitor to the "index" page of the current directory.\&
+.PP
+Example: If a visitor is looking at "/view/projects/wiki" and follows a link to
+"index", they end up on "/view/projects/index", not on "/view/index".\&
+.PP
+.SH SEE ALSO
 .PP
 \fIoddmu\fR(1)
 .PP
@@ -137,16 +180,15 @@ https://developer.\&mozilla.\&org/en-US/docs/Learn/HTML
 "Learn to style HTML using CSS"
 https://developer.\&mozilla.\&org/en-US/docs/Learn/CSS
 .PP
-The "text/template" library explains how to write templates from a
-programmer perspective.\& https://pkg.\&go.\&dev/text/template
+The "text/template" library explains how to write templates from a programmer
+perspective.\& https://pkg.\&go.\&dev/text/template
 .PP
-The "html/template" library explains how the templates are made more
-secure in a HTML context.\& https://pkg.\&go.\&dev/html/template
+The "html/template" library explains how the templates are made more secure in a
+HTML context.\& https://pkg.\&go.\&dev/html/template
 .PP
 "Lingua" is the library used to detect languages.\&
 https://github.\&com/pemistahl/lingua-go
 .PP
 .SH AUTHORS
 .PP
-Maintained by Alex Schroeder <alex@gnu.\&org>.\& Up-to-date sources can be
-found at https://alexschroeder.\&ch/cgit/oddmu/.\&
+Maintained by Alex Schroeder <alex@gnu.\&org>.\&

man/oddmu-templates.5.txt

@@ -8,38 +8,49 @@ oddmu-templates - how to write the templates
 
 The templates can refer to the following properties of a page:
 
-_{{.Title}}_ is the page title. If the page doesn't provide its own
-title, the page name is used.
+_{{.Title}}_ is the page title. If the page doesn't provide its own title, the
+page name is used.
 
-_{{.Name}}_ is the page name, escaped for use in URLs. More
-specifically, it is URI escaped except for the slashes. The page name
-doesn't include the _.md_ extension.
+_{{.Name}}_ is the page name, escaped for use in URLs. More specifically, it is
+percent-escaped except for the slashes. The page name doesn't include the _.md_
+extension.
 
-For the _view.html_ template:
+_{{.Dir}}_ is the page directory, percent-escaped except for the slashes.
+
+_{{.Today}}_ is the current date, in ISO format. This is useful for "new page"
+like links or forms (see *EXAMPLE* below).
+
+For the _view.html_ and _static.html_ template:
 
 _{{.Html}}_ is the rendered Markdown, as HTML.
 
 _{{.Hashtags}}_ is an array of strings.
 
+For the _diff.html_ template:
+
+_{{.Diff}}_ is the diff for this page. This is only computed on demand so it can
+be used in other templates, too. It probably doesn't make much sense to do so,
+however.
+
 For the _edit.html_ template:
 
-_{{printf "%s" .Body}}_ is the Markdown, as a string (the data itself
-is a byte array and that's why we need to call _printf_).
+_{{printf "%s" .Body}}_ is the Markdown, as a string (the data itself is a byte
+array and that's why we need to call _printf_).
 
 For the _search.html_ template only:
 
-_{{.Previous}}_, _{{.Page}}_, _{{.Next}}_ and _{{.Last}}_ are the
-previous, current, next and last page number in the results since
-doing arithmetics in templates is hard. The first page number is 1.
+_{{.Previous}}_, _{{.Page}}_ and _{{.Next}}_ are the previous, current and next
+page number in the results since doing arithmetics in templates is hard. The
+first page number is 1. The last page is expensive to dermine and so that isn't
+done.
 
 _{{.More}}_ indicates if there are any more search results.
 
 _{{.Results}}_ indicates if there were any search results at all.
 
-_{{.Items}}_ is an array of pages, each containing a search result. A
-search result is a page (with the properties seen above). Thus, to
-refer to them, you need to use a _{{range .Items}}_ … _{{end}}_
-construct.
+_{{.Items}}_ is an array of pages, each containing a search result. A search
+result is a page (with the properties seen above). Thus, to refer to them, you
+need to use a _{{range .Items}}_ … _{{end}}_ construct.
 
 For items in the search result:
 
@@ -53,8 +64,8 @@ _{{.Name}}_ is the page name, escaped for use in URLs.
 
 _{{.Title}}_ is the title of the underlying main page.
 
-_{{.Date}}_ is the date of the last update to the underlying main page,
-in RFC 822 format.
+_{{.Date}}_ is the date of the last update to the underlying main page, in RFC
+822 format.
 
 _{{.Items}}_ is an array of feed items.
 
@@ -68,55 +79,83 @@ _{{.Html}}_ is the rendered Markdown, as escaped (!) HTML.
 
 _{{.Hashtags}}_ is an array of strings.
 
-_{{.Date}}_, the date of the last update to this page, in RFC 822
-format.
+_{{.Date}}_, the date of the last update to this page, in RFC 822 format.
 
 The _upload.html_ template cannot refer to anything.
 
-When calling the _save_ and _append_ action, the page name is taken
-from the URL path and the page content is taken from the _body_ form
-parameter. To illustrate, here's how to edit the "welcome" page using
-_curl_:
+When calling the _save_ and _append_ action, the page name is taken from the URL
+path and the page content is taken from the _body_ form parameter. To
+illustrate, here's how to edit the "welcome" page using _curl_:
 
 ```
 curl --form body="Did you bring a towel?" \
   http://localhost:8080/save/welcome
 ```
 
-When calling the _search_ action, the query is taken from the URL
-parameter _q_.
+When calling the _search_ action, the query is taken from the URL parameter _q_.
 
 ```
-curl http://localhost:8080/search?q=towel
+curl http://localhost:8080/search/?q=towel
 ```
 
 ## Non-English hyphenation
 
-Automatic hyphenation by the browser requires two things: The style
-sheet must indicate "hyphen: auto" for an HTML element such as "body",
-and that element must have a "lang" set (usually a two letter language
-code such as "de" for German).
+Automatic hyphenation by the browser requires two things: The style sheet must
+indicate "hyphen: auto" for an HTML element such as "body", and that element
+must have a "lang" set (usually a two letter language code such as "de" for
+German).
 
-Oddmu attempts to detect the correct language for each page. It
-assumes that languages are not mixed on the same page. If you know
-that you're only going to use a small number of languages – or just a
-single language! – you can set the environment variable
-ODDMU_LANGUAGES to a comma-separated list of ISO 639-1 codes, e.g.
-"en" or "en,de,fr,pt".
+Oddmu attempts to detect the correct language for each page. It assumes that
+languages are not mixed on the same page. If you know that you're only going to
+use a small number of languages – or just a single language! – you can set the
+environment variable ODDMU_LANGUAGES to a comma-separated list of ISO 639-1
+codes, e.g. "en" or "en,de,fr,pt".
 
-"view.html" is used the template to render a single page and so the
-language detected is added to the "html" element.
+"view.html" is used the template to render a single page and so the language
+detected is added to the "html" element.
 
-"search.html" is the template used to render search results and so
-"en" is used for the "html" element and the language detected for
-every page in the search result is added to the "article" element for
-each snippet.
+"search.html" is the template used to render search results and so "en" is used
+for the "html" element and the language detected for every page in the search
+result is added to the "article" element for each snippet.
 
-"edit.html" and "add.html" are the templates used to edit a page and
-at that point, the language isn't known, so "en" is used for the
-"html" element and no language is used for the "textarea" element.
+"edit.html" and "add.html" are the templates used to edit a page and at that
+point, the language isn't known, so "en" is used for the "html" element and no
+language is used for the "textarea" element.
 
-SEE ALSO
+# EXAMPLE
+
+The following link in a template takes people to today's page. If no such page
+exists, they are redirected to the edit form where it can be created.
+
+```
+<a href="/view/{{.Today}}" accesskey="t">Today</a>
+```
+
+The following form allows people to edit the suggested page name.
+
+```
+<form role="new" action="/edit/{{.Dir}}" method="GET">
+  <label for="id">New page:</label>
+  <input id="id" type="text" spellcheck="false" name="id"
+	  accesskey="g" value="{{.Today}}" required>
+  <button>Edit</button>
+</form>
+```
+
+# NOTES
+
+The template are always used as-is, irrespective of the current directory.
+Therefore, a link to a specific page must be _absolute_ or it'll point to a
+different page depending on the current directory.
+
+Consider the link to "/view/index". No matter what page a visitor is looking,
+this takes visitors to the top "index" page. If the link points to "index"
+instead, it takes a visitor to the "index" page of the current directory.
+
+Example: If a visitor is looking at "/view/projects/wiki" and follows a link to
+"index", they end up on "/view/projects/index", not on "/view/index".
+
+# SEE ALSO
 
 _oddmu_(1)
 
@@ -126,16 +165,15 @@ https://developer.mozilla.org/en-US/docs/Learn/HTML
 "Learn to style HTML using CSS"
 https://developer.mozilla.org/en-US/docs/Learn/CSS
 
-The "text/template" library explains how to write templates from a
-programmer perspective. https://pkg.go.dev/text/template
+The "text/template" library explains how to write templates from a programmer
+perspective. https://pkg.go.dev/text/template
 
-The "html/template" library explains how the templates are made more
-secure in a HTML context. https://pkg.go.dev/html/template
+The "html/template" library explains how the templates are made more secure in a
+HTML context. https://pkg.go.dev/html/template
 
 "Lingua" is the library used to detect languages.
 https://github.com/pemistahl/lingua-go
 
 # AUTHORS
 
-Maintained by Alex Schroeder <alex@gnu.org>. Up-to-date sources can be
-found at https://alexschroeder.ch/cgit/oddmu/.
+Maintained by Alex Schroeder <alex@gnu.org>.

man/oddmu.1

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU" "1" "2023-09-22"
+.TH "ODDMU" "1" "2023-11-24"
 .PP
 .SH NAME
 .PP
@@ -31,15 +31,19 @@ is "index.\&md".\& If no such file exists, oddmu offers you to create the page.\
 If your files don'\&t provide their own title ("# title"), the file name (without
 ".\&md") is used for the page title.\&
 .PP
+Every file can be viewed as feed by using the extension ".\&rss".\& The
+feed items are based on links in bullet lists using the asterix
+("*").\&
+.PP
 Subdirectories are created as necessary.\&
 .PP
 See \fIoddmu\fR(5) for details about the page formatting.\&
 .PP
 .SH CONFIGURATION
 .PP
-The template files are the HTML files in the working directory: "add.\&html",
-"edit.\&html", "search.\&html", "upload.\&html" and "view.\&html".\& Feel free to change
-the templates and restart the server.\&
+The template files are the HTML files in the working directory:
+"add.\&html", "diff.\&html", "edit.\&html", "search.\&html", "upload.\&html" and
+"view.\&html".\& Feel free to change the templates and restart the server.\&
 .PP
 The first change you should make is to replace the name and email
 address in the footer of "view.\&html".\& Look for "Your Name" and
@@ -48,7 +52,7 @@ address in the footer of "view.\&html".\& Look for "Your Name" and
 The second change you should make is to replace the name, email
 address and domain name in "feed.\&html".\& Look for "Your Name" and
 "example.\&org".\& This second template is used to generate the RSS feeds
-(despite it'\&s ".\&html" extension).\&
+(despite its ".\&html" extension).\&
 .PP
 See \fIoddmu-templates\fR(5) for more.\&
 .PP
@@ -71,13 +75,20 @@ server as a reverse proxy.\&
 .PP
 See \fIoddmu-apache\fR(5) for an example.\&
 .PP
+Oddmu assumes that all the users that can edit pages or upload files are trusted
+users and therefore their content is trusted.\& Therefore, Oddmu doesn'\&t perform
+HTML sanitization!\&
+.PP
 .SH OPTIONS
 .PP
 The oddmu program can be run on the command-line using various subcommands.\&
 .PP
 .PD 0
 .IP \(bu 4
-to generate the HTML for a page, see \fIoddmu-html\fR(1)
+to generate the HTML for a single page, see \fIoddmu-html\fR(1)
+.IP \(bu 4
+to generate the HTML for the entire site, using Oddmu as a static site
+generator, see \fIoddmu-static\fR(1)
 .IP \(bu 4
 to search a regular expression and replace it across all files, see
 \fIoddmu-replace\fR(1)
@@ -85,13 +96,18 @@ to search a regular expression and replace it across all files, see
 to emulate a search of the files, see \fIoddmu-search\fR(1); to understand how the
 search engine indexes pages and how it sorts and scores results, see
 \fIoddmu-search\fR(7)
+.IP \(bu 4
+to find missing pages (local links that go nowhere), see \fIoddmu-missing\fR(1)
+.IP \(bu 4
+to add links to changes, index and hashtag pages to pages you created locally,
+see \fIoddmu-notify\fR(1)
 .PD
 .PP
 .SH EXAMPLE
 .PP
-When saving a page, the page name is take from the URL and the page
-content is taken from the "body" form parameter.\& To illustrate, here'\&s
-how to edit a page using \fIcurl\fR(1):
+When saving a page, the page name is take from the URL and the page content is
+taken from the "body" form parameter.\& To illustrate, here'\&s how to edit a page
+using \fIcurl\fR(1):
 .PP
 .nf
 .RS 4
@@ -107,13 +123,6 @@ This is a minimal wiki.\& There is no version history.\& It'\&s well suited as a
 on social media.\& The wiki serves as the text repository that results from these
 discussions.\&
 .PP
-The wiki lists no recent changes.\& The expectation is that the people that care
-were involved in the discussions beforehand.\&
-.PP
-The wiki also produces no feed.\& The assumption is that announcements are made on
-social media: blogs, news aggregators, discussion forums, the fediverse, but
-humans.\&
-.PP
 The idea is that the webserver handles as many tasks as possible.\& It logs
 requests, does rate limiting, handles encryption, gets the certificates, and so
 on.\& The web server acts as a reverse proxy and the wiki ends up being a content
@@ -123,24 +132,97 @@ on your point of view.\& See \fIoddmu-apache\fR(5).\&
 .SH NOTES
 .PP
 Page names are filenames with ".\&md" appended.\& If your filesystem cannot handle
-it, it can'\&t be a page name.\&
+it, it can'\&t be a page name.\& Filenames can contain slashes and oddmu creates
+subdirectories as necessary.\&
 .PP
-The pages are indexed as the server starts and the index is kept in memory.\& If
-you have a ton of pages, this takes a lot of memory.\&
+Files may not end with a tilde ('\&~'\&) – these are backup files.\& When saving pages
+and file uploads, the old file renamed to the backup file unless the backup file
+is less than an hour old, thus collapsing all edits made in an hour into a
+single diff when comparing backup and current version.\&
 .PP
-Files may not end with a tilde ('\&~'\&) – these are backup files.\&
+The \fBindex\fR page is the default page.\& People visiting the "root" of the site are
+redirected to "/view/index".\&
+.PP
+The \fBchanges\fR page is where links to new and changed files are added.\& As an
+author, you can prevent this from happening by deselecting the checkbox "Add
+link to the list of changes.\&" The changes page can be edited like every other
+page, so it'\&s easy to undo mistakes.\&
+.PP
+Links on the changes page are grouped by date.\& When new links are added, the
+current date of the machine Oddmu is running on is used.\& If a link already
+exists on the changes page, it is moved up to the current date.\& If that leaves
+an old date without any links, that date heading is removed.\&
+.PP
+If you want to link to the changes page, you need to do this yourself.\& Add a
+link from the index, for example.\& The "view.\&html" template currently doesn'\&t do
+it.\& See \fIoddmu-templates\fR(5) if you want to add the link to the template.\&
+.PP
+A page whose name starts with an ISO date (YYYY-MM-DD, e.\&g.\& "2023-10-28") is
+called a \fBblog\fR page.\& When creating or editing blog pages, links to it are added
+from other pages.\&
+.PP
+If the blog page name starts with the current year, a link is created from the
+index page back to the blog page being created or edited.\& Again, you can prevent
+this from happening by deselecting the checkbox "Add link to the list of
+changes.\&" The index page can be edited like every other page, so it'\&s easy to
+undo mistakes.\&
+.PP
+For every \fBhashtag\fR used, another link might be created.\& If a page named like
+the hashtag exists, a backlink is added to it, linking to the new or edited blog
+page.\&
+.PP
+If a link to the new or edited blog page already exists but it'\&s title is no
+longer correct, it is updated.\&
+.PP
+New links added for blog pages are added at the top of the first unnumbered list
+using the asterisk ('\&*'\&).\& If no such list exists, a new one is started at the
+bottom of the page.\& This allows you to have a different unnumbered list further
+up on the page, as long as it uses the minus for items ('\&-'\&).\&
+.PP
+Changes made locally do not create any links on the changes page, the index page
+or on any hashtag pages.\& See \fIoddmu-notify\fR(1) for a way to add the necessary
+links to the changes page and possibly to the index and hashtag pages.\&
+.PP
+A hashtag consists of a number sign ('\&#'\&) followed by Unicode letters, numbers
+or the underscore ('\&_'\&).\& Thus, a hashtag ends with punctuation or whitespace.\&
+.PP
+The page names, titles and hashtags are loaded into memory when the server
+starts.\& If you have a lot of pages, this takes a lot of memory.\& If you change
+the files while the wiki runs, changes to names (creating, renaming or deleting
+files), titles or hashtags confuse Oddmu.\& Restart the program in order to
+resolve this.\&
 .PP
 You cannot edit uploaded files.\& If you upload a file called "hello.\&txt" and
-attempt to edit it by using "/edit/hello.\&txt" you will create a page with the
-name "hello.\&txt.\&md" instead.\&
+attempt to edit it by using "/edit/hello.\&txt" you create a page with the name
+"hello.\&txt.\&md" instead.\&
 .PP
 You cannot delete uploaded files via the web – but you can delete regular wiki
-pages by saving an empty file.\&
+pages by saving an empty page.\&
 .PP
 .SH SEE ALSO
 .PP
-\fIoddmu\fR(5), \fIoddmu.\&service\fR(5), oddmu-apache_(5), \fIoddmu-html\fR(1),
-\fIoddmu-replace\fR(1), \fIoddmu-search\fR(1), \fIoddmu-search\fR(7), \fIoddmu-feed\fR(1)
+.PD 0
+.IP \(bu 4
+\fIoddmu\fR(5), about the markup syntax and how feeds are generated based on link lists
+.IP \(bu 4
+\fIoddmu.\&service\fR(5), on how to run the service under systemd
+.IP \(bu 4
+\fIoddmu-apache\fR(5), on how to set up a web server such as Apache
+.IP \(bu 4
+\fIoddmu-html\fR(1), on how to render a page from the command-line
+.IP \(bu 4
+\fIoddmu-missing\fR(1), on how to find broken local links from the command-line
+.IP \(bu 4
+\fIoddmu-replace\fR(1), on how to search and replace text from the command-line
+.IP \(bu 4
+\fIoddmu-search\fR(1), on how to run a search from the command-line
+.IP \(bu 4
+\fIoddmu-search\fR(7), on how search works
+.IP \(bu 4
+\fIoddmu-static\fR(1), on generating a static site from the command-line
+.IP \(bu 4
+\fIoddmu-templates\fR(5), on how to write the HTML templates
+.PD
 .PP
 .SH AUTHORS
 .PP

man/oddmu.1.txt

@@ -25,7 +25,8 @@ If your files don't provide their own title ("# title"), the file name (without
 ".md") is used for the page title.
 
 Every file can be viewed as feed by using the extension ".rss". The
-feed items are based on links in bullet lists using the asterix ("*").
+feed items are based on links in bullet lists using the asterix
+("\*").
 
 Subdirectories are created as necessary.
 
@@ -33,9 +34,9 @@ See _oddmu_(5) for details about the page formatting.
 
 # CONFIGURATION
 
-The template files are the HTML files in the working directory: "add.html",
-"edit.html", "search.html", "upload.html" and "view.html". Feel free to change
-the templates and restart the server.
+The template files are the HTML files in the working directory:
+"add.html", "diff.html", "edit.html", "search.html", "upload.html" and
+"view.html". Feel free to change the templates and restart the server.
 
 The first change you should make is to replace the name and email
 address in the footer of "view.html". Look for "Your Name" and
@@ -44,7 +45,7 @@ address in the footer of "view.html". Look for "Your Name" and
 The second change you should make is to replace the name, email
 address and domain name in "feed.html". Look for "Your Name" and
 "example.org". This second template is used to generate the RSS feeds
-(despite it's ".html" extension).
+(despite its ".html" extension).
 
 See _oddmu-templates_(5) for more.
 
@@ -67,22 +68,31 @@ server as a reverse proxy.
 
 See _oddmu-apache_(5) for an example.
 
+Oddmu assumes that all the users that can edit pages or upload files are trusted
+users and therefore their content is trusted. Therefore, Oddmu doesn't perform
+HTML sanitization!
+
 # OPTIONS
 
 The oddmu program can be run on the command-line using various subcommands.
 
-- to generate the HTML for a page, see _oddmu-html_(1)
+- to generate the HTML for a single page, see _oddmu-html_(1)
+- to generate the HTML for the entire site, using Oddmu as a static site
+  generator, see _oddmu-static_(1)
 - to search a regular expression and replace it across all files, see
   _oddmu-replace_(1)
 - to emulate a search of the files, see _oddmu-search_(1); to understand how the
   search engine indexes pages and how it sorts and scores results, see
   _oddmu-search_(7)
+- to find missing pages (local links that go nowhere), see _oddmu-missing_(1)
+- to add links to changes, index and hashtag pages to pages you created locally,
+  see _oddmu-notify_(1)
 
 # EXAMPLE
 
-When saving a page, the page name is take from the URL and the page
-content is taken from the "body" form parameter. To illustrate, here's
-how to edit a page using _curl_(1):
+When saving a page, the page name is take from the URL and the page content is
+taken from the "body" form parameter. To illustrate, here's how to edit a page
+using _curl_(1):
 
 ```
 curl --form body="Did you bring a towel?" \
@@ -96,9 +106,6 @@ _secondary_ medium: collaboration and conversation happens elsewhere, in chat,
 on social media. The wiki serves as the text repository that results from these
 discussions.
 
-The wiki lists no recent changes. The expectation is that the people that care
-were involved in the discussions beforehand.
-
 The idea is that the webserver handles as many tasks as possible. It logs
 requests, does rate limiting, handles encryption, gets the certificates, and so
 on. The web server acts as a reverse proxy and the wiki ends up being a content
@@ -108,24 +115,85 @@ on your point of view. See _oddmu-apache_(5).
 # NOTES
 
 Page names are filenames with ".md" appended. If your filesystem cannot handle
-it, it can't be a page name.
+it, it can't be a page name. Filenames can contain slashes and oddmu creates
+subdirectories as necessary.
 
-The pages are indexed as the server starts and the index is kept in memory. If
-you have a ton of pages, this takes a lot of memory.
+Files may not end with a tilde ('~') – these are backup files. When saving pages
+and file uploads, the old file renamed to the backup file unless the backup file
+is less than an hour old, thus collapsing all edits made in an hour into a
+single diff when comparing backup and current version.
 
-Files may not end with a tilde ('~') – these are backup files.
+The *index* page is the default page. People visiting the "root" of the site are
+redirected to "/view/index".
+
+The *changes* page is where links to new and changed files are added. As an
+author, you can prevent this from happening by deselecting the checkbox "Add
+link to the list of changes." The changes page can be edited like every other
+page, so it's easy to undo mistakes.
+
+Links on the changes page are grouped by date. When new links are added, the
+current date of the machine Oddmu is running on is used. If a link already
+exists on the changes page, it is moved up to the current date. If that leaves
+an old date without any links, that date heading is removed.
+
+If you want to link to the changes page, you need to do this yourself. Add a
+link from the index, for example. The "view.html" template currently doesn't do
+it. See _oddmu-templates_(5) if you want to add the link to the template.
+
+A page whose name starts with an ISO date (YYYY-MM-DD, e.g. "2023-10-28") is
+called a *blog* page. When creating or editing blog pages, links to it are added
+from other pages.
+
+If the blog page name starts with the current year, a link is created from the
+index page back to the blog page being created or edited. Again, you can prevent
+this from happening by deselecting the checkbox "Add link to the list of
+changes." The index page can be edited like every other page, so it's easy to
+undo mistakes.
+
+For every *hashtag* used, another link might be created. If a page named like
+the hashtag exists, a backlink is added to it, linking to the new or edited blog
+page.
+
+If a link to the new or edited blog page already exists but it's title is no
+longer correct, it is updated.
+
+New links added for blog pages are added at the top of the first unnumbered list
+using the asterisk ('\*'). If no such list exists, a new one is started at the
+bottom of the page. This allows you to have a different unnumbered list further
+up on the page, as long as it uses the minus for items ('-').
+
+Changes made locally do not create any links on the changes page, the index page
+or on any hashtag pages. See _oddmu-notify_(1) for a way to add the necessary
+links to the changes page and possibly to the index and hashtag pages.
+
+A hashtag consists of a number sign ('#') followed by Unicode letters, numbers
+or the underscore ('\_'). Thus, a hashtag ends with punctuation or whitespace.
+
+The page names, titles and hashtags are loaded into memory when the server
+starts. If you have a lot of pages, this takes a lot of memory. If you change
+the files while the wiki runs, changes to names (creating, renaming or deleting
+files), titles or hashtags confuse Oddmu. Restart the program in order to
+resolve this.
 
 You cannot edit uploaded files. If you upload a file called "hello.txt" and
-attempt to edit it by using "/edit/hello.txt" you will create a page with the
-name "hello.txt.md" instead.
+attempt to edit it by using "/edit/hello.txt" you create a page with the name
+"hello.txt.md" instead.
 
 You cannot delete uploaded files via the web – but you can delete regular wiki
-pages by saving an empty file.
+pages by saving an empty page.
 
 # SEE ALSO
 
-_oddmu_(5), _oddmu.service_(5), oddmu-apache_(5), _oddmu-html_(1),
-_oddmu-replace_(1), _oddmu-search_(1), _oddmu-search_(7)
+- _oddmu_(5), about the markup syntax and how feeds are generated based on link lists
+- _oddmu.service_(5), on how to run the service under systemd
+- _oddmu-apache_(5), on how to set up a web server such as Apache
+- _oddmu-html_(1), on how to render a page from the command-line
+- _oddmu-missing_(1), on how to find broken local links from the command-line
+- _oddmu-replace_(1), on how to search and replace text from the command-line
+- _oddmu-search_(1), on how to run a search from the command-line
+- _oddmu-search_(7), on how search works
+- _oddmu-static_(1), on generating a static site from the command-line
+- _oddmu-templates_(5), on how to write the HTML templates
 
 # AUTHORS
 

man/oddmu.5

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU" "5" "2023-09-21" "File Formats Manual"
+.TH "ODDMU" "5" "2023-11-12" "File Formats Manual"
 .PP
 .SH NAME
 .PP
@@ -13,26 +13,41 @@ oddmu - text formatting of wiki pages
 .PP
 .SH SYNTAX
 .PP
-The wiki pages are UTF-8 encoded Markdown files.\&
-.PP
-There are three Oddµ-specific extensions: local links, hashtags and
-fediverse account links.\& The Markdown library used features some
-additional extensions, most importantly tables and definition lists.\&
-.PP
-.SS Local links
-.PP
-Local links use double square brackets [[like this]].\&
-.PP
-.SS Hashtags
-.PP
-Hashtags are single word links to searches for themselves.\& Use the
-underscore to use hashtags consisting of multiple words.\& Hashtags are
-distinguished from page titles because there is no space after the
-hash.\&
+The wiki pages are UTF-8 encoded Markdown files (with the ".\&md" extension).\&
+Oddmu links are regular Markdown links to page names (without the ".\&md"
+extension):
 .PP
 .nf
 .RS 4
-# Title
+[link text](page-name)
+.fi
+.RE
+.PP
+The page name has to be percent-encoded.\& See the section "Percent Encoding".\&
+.PP
+If you link to the actual Markdown file (with the ".\&md" extension), then Oddmu
+serves the Markdown file!\&
+.PP
+There are three Oddµ-specific extensions: local links, hashtags and fediverse
+account links.\& The Markdown library used features some additional extensions,
+most importantly tables and definition lists.\&
+.PP
+.SS Local links
+.PP
+Local links use double square brackets [[like this]].\& Oddmu does not treat
+underscores like spaces, so [[like this]] and [[like_this]] link to different
+destinations and are served by different files: "like this.\&md" and
+"like_this.\&md".\&
+.PP
+.SS Hashtags
+.PP
+Hashtags are single word links to searches for themselves.\& Use the underscore to
+use hashtags consisting of multiple words.\& Hashtags are distinguished from page
+titles because there is no space after the hash.\&
+.PP
+.nf
+.RS 4
+# Example
 
 Text
 
@@ -40,6 +55,11 @@ Text
 .fi
 .RE
 .PP
+When a page containing hashtags is saved, a link to that page is added to every
+page with the same name as the hashtag, if it exists.\& In the example above, if
+the file "Tag.\&md" or the file "Another_Tag.\&md" exists, a link to the Example
+page is added.\&
+.PP
 .SS Tables
 .PP
 A table with footers and a columnspan:
@@ -69,58 +89,116 @@ Internet
 .PP
 .SS Fediverse account links
 .PP
-Fediverse accounts look a bit like an at sign followed by an email
-address, e.\&g.\& @alex@alexschroeder.\&ch.\& When rendering a page, these
-turn into a username linked to a profile page.\& In this case, "@alex"
-would be linked to "https://alexschroeder.\&ch/users/alex".\&
+Fediverse accounts look a bit like an at sign followed by an email address, e.\&g.\&
+@alex@alexschroeder.\&ch.\& When rendering a page, these turn into a username linked
+to a profile page.\& In this case, "@alex" would be linked to
+"https://alexschroeder.\&ch/users/alex".\&
 .PP
-In many cases, this will work as is.\& In reality, however, the link to
-the profile page needs to be retrieved via webfinger.\& Oddµ does that
-in the background, and as soon as the information is available, the
-actual profile link is used when pages are rendered.\& In the example
-above, the result would be "https://social.\&alexschroeder.\&ch/@alex".\&
+In many cases, this works as is.\& In reality, however, the link to the profile
+page needs to be retrieved via webfinger.\& Oddµ does that in the background, and
+as soon as the information is available, the actual profile link is used when
+pages are rendered.\& In the example above, the result would be
+"https://social.\&alexschroeder.\&ch/@alex".\&
 .PP
-As this sort of packground network activity is surprising, it is not
-enabled by default.\& Set the environment variable ODDMU_WEBFINGER to
-"1" in order to enable this.\&
+As this sort of packground network activity is surprising, it is not enabled by
+default.\& Set the environment variable ODDMU_WEBFINGER to "1" in order to enable
+this.\&
 .PP
 .SS Other extensions
 .PP
 The Markdown processor comes with a few extensions:
 .PP
-\fB emphasis markers inside words are ignored
-\fR fenced code blocks are supported
-\fB autolinking of "naked" URLs are supported
-\fR strikethrough using two tildes is supported (~~like this~~)
-\fB it is strict about prefix heading rules
-\fR you can specify an id for headings ({#id})
-\fB trailing backslashes turn into line breaks
-\fR MathJax is supported (but needs a separte setup)
+.PD 0
+.IP \(bu 4
+emphasis markers inside words are ignored
+.IP \(bu 4
+fenced code blocks are supported
+.IP \(bu 4
+autolinking of "naked" URLs are supported
+.IP \(bu 4
+strikethrough using two tildes is supported (~~like this~~)
+.IP \(bu 4
+it is strict about prefix heading rules
+.IP \(bu 4
+you can specify an id for headings ({#id})
+.IP \(bu 4
+trailing backslashes turn into line breaks
+.PD
+.PP
+.SH FEEDS
+.PP
+Every file can be viewed as feed by using the extension ".\&rss".\& The feed items
+are based on links in bullet lists using the asterix ("*").\& The items must
+point to local pages.\& This is why the link may not contain two forward slashes
+("//").\&
+.PP
+Assume this is the index page.\& The feed would be "/view/index.\&rss".\& It would
+contain the pages "Arianism", "Donatism" and "Monophysitism" but it would not
+contain the pages "Feed" and "About" since the list items don'\&t start with an
+asterix.\&
+.PP
+.nf
+.RS 4
+# Main Page
+
+Hello and welcome! Here are some important links:
+
+- [Feed](index\&.rss)
+- [About](about)
+
+Recent posts:
+
+* [Arianism](arianism)
+* [Donatism](donatism)
+* [Monophysitism](monophysitism)
+.fi
+.RE
+.PP
+The feed contains at most 10 items, starting at the top.\&
 .PP
 .SH PERCENT ENCODING
 .PP
-If you use Markdown links to local pages, you must percent-encode the
-link target.\& Any character that is not an "unreserved character"
-according to RFC 3986 might need to be encoded.\& The unreserved
-characters are a-z, A-Z, 0-9, as well as the four characters '\&-'\&,
-\&'\&_'\&, '\&.\&'\& and '\&~'\&.\&
+If you use Markdown links to local pages, you must percent-encode the link
+target.\& Any character that is not an "unreserved character" according to RFC
+3986 might need to be encoded.\& The unreserved characters are a-z, A-Z, 0-9, as
+well as the four characters '\&-'\&, '\&_'\&, '\&.\&'\& and '\&~'\&.\&
 .PP
-Percent-encoding means that each character is converted into one or
-more bytes, and each byte is represented as a percent character
-followed by a hexadecimal representation.\&
+Percent-encoding means that each character is converted into one or more bytes,
+and each byte is represented as a percent character followed by a hexadecimal
+representation.\&
 .PP
-Realistically, what probably works best is to use a browser.\& If you
-type "http://example.\&org/Alex Schröder" into the address bar, you'\&ll
-get sent to the example domain.\& If you now copy the address and paste
-it back into a text editor, you'\&ll get
-"http://example.\&org/Alex%20Schr%C3%B6der" and that'\&s how you'\&ll learn
-that the Space is encoded by %20 and that the character '\&ö'\& is encoded
-by %C3%B6.\& To link to the page "Alex Schröder" you would write
-something like this: "[Alex](Alex%20Schr%C3%B6der)".\&
+Realistically, what probably works best is to use a browser.\& If you type
+"http://example.\&org/Alex Schröder" into the address bar, you'\&ll get sent to the
+example domain.\& If you now copy the address and paste it back into a text
+editor, you'\&ll get "http://example.\&org/Alex%20Schr%C3%B6der" and that'\&s how
+you'\&ll learn that the Space is encoded by %20 and that the character '\&ö'\& is
+encoded by %C3%B6.\& To link to the page "Alex Schröder" you would write something
+like this: "[Alex](Alex%20Schr%C3%B6der)".\&
+.PP
+Another thing that'\&s common is that your page name contains a colon.\&
+This is legal.\& The URL parser might still reject it.\& If you run the
+"missing" subcommand, you'\&ll get to see error: "first path segment in
+URL cannot contain colon".\& The solution is to prepend ".\&/"!\&
+.PP
+Example:
+.PP
+.nf
+.RS 4
+[2021-10-15 Re: Mark It Down](2021-10-15_Re:_Mark_It_Down)
+.fi
+.RE
+.PP
+Fixed:
+.PP
+.nf
+.RS 4
+[2021-10-15 Re: Mark It Down](\&./2021-10-15_Re:_Mark_It_Down)
+.fi
+.RE
 .PP
 .SH SEE ALSO
 .PP
-\fIoddmu\fR(1)
+\fIoddmu\fR(1), \fIoddmu-missing\fR(1)
 .PP
 This wiki uses the Go Markdown library.\&
 https://github.\&com/gomarkdown/markdown

man/oddmu.5.txt

@@ -6,31 +6,49 @@ oddmu - text formatting of wiki pages
 
 # SYNTAX
 
-The wiki pages are UTF-8 encoded Markdown files.
+The wiki pages are UTF-8 encoded Markdown files (with the ".md" extension).
+Oddmu links are regular Markdown links to page names (without the ".md"
+extension):
 
-There are three Oddµ-specific extensions: local links, hashtags and
-fediverse account links. The Markdown library used features some
-additional extensions, most importantly tables and definition lists.
+```
+[link text](page-name)
+```
+
+The page name has to be percent-encoded. See the section "Percent Encoding".
+
+If you link to the actual Markdown file (with the ".md" extension), then Oddmu
+serves the Markdown file!
+
+There are three Oddµ-specific extensions: local links, hashtags and fediverse
+account links. The Markdown library used features some additional extensions,
+most importantly tables and definition lists.
 
 ## Local links
 
-Local links use double square brackets [[like this]].
+Local links use double square brackets [[like this]]. Oddmu does not treat
+underscores like spaces, so [[like this]] and [[like_this]] link to different
+destinations and are served by different files: "like this.md" and
+"like_this.md".
 
 ## Hashtags
 
-Hashtags are single word links to searches for themselves. Use the
-underscore to use hashtags consisting of multiple words. Hashtags are
-distinguished from page titles because there is no space after the
-hash.
+Hashtags are single word links to searches for themselves. Use the underscore to
+use hashtags consisting of multiple words. Hashtags are distinguished from page
+titles because there is no space after the hash.
 
 ```
-# Title
+# Example
 
 Text
 
 #Tag #Another_Tag
 ```
 
+When a page containing hashtags is saved, a link to that page is added to every
+page with the same name as the hashtag, if it exists. In the example above, if
+the file "Tag.md" or the file "Another_Tag.md" exists, a link to the Example
+page is added.
+
 ## Tables
 
 A table with footers and a columnspan:
@@ -56,45 +74,44 @@ Internet
 
 ## Fediverse account links
 
-Fediverse accounts look a bit like an at sign followed by an email
-address, e.g. @alex@alexschroeder.ch. When rendering a page, these
-turn into a username linked to a profile page. In this case, "@alex"
-would be linked to "https://alexschroeder.ch/users/alex".
+Fediverse accounts look a bit like an at sign followed by an email address, e.g.
+@alex@alexschroeder.ch. When rendering a page, these turn into a username linked
+to a profile page. In this case, "@alex" would be linked to
+"https://alexschroeder.ch/users/alex".
 
-In many cases, this will work as is. In reality, however, the link to
-the profile page needs to be retrieved via webfinger. Oddµ does that
-in the background, and as soon as the information is available, the
-actual profile link is used when pages are rendered. In the example
-above, the result would be "https://social.alexschroeder.ch/@alex".
+In many cases, this works as is. In reality, however, the link to the profile
+page needs to be retrieved via webfinger. Oddµ does that in the background, and
+as soon as the information is available, the actual profile link is used when
+pages are rendered. In the example above, the result would be
+"https://social.alexschroeder.ch/@alex".
 
-As this sort of packground network activity is surprising, it is not
-enabled by default. Set the environment variable ODDMU_WEBFINGER to
-"1" in order to enable this.
+As this sort of packground network activity is surprising, it is not enabled by
+default. Set the environment variable ODDMU_WEBFINGER to "1" in order to enable
+this.
 
 ## Other extensions
 
 The Markdown processor comes with a few extensions:
 
-* emphasis markers inside words are ignored
-* fenced code blocks are supported
-* autolinking of "naked" URLs are supported
-* strikethrough using two tildes is supported (~~like this~~)
-* it is strict about prefix heading rules
-* you can specify an id for headings ({#id})
-* trailing backslashes turn into line breaks
-* MathJax is supported (but needs a separte setup)
+- emphasis markers inside words are ignored
+- fenced code blocks are supported
+- autolinking of "naked" URLs are supported
+- strikethrough using two tildes is supported (~~like this~~)
+- it is strict about prefix heading rules
+- you can specify an id for headings ({#id})
+- trailing backslashes turn into line breaks
 
 # FEEDS
 
-Every file can be viewed as feed by using the extension ".rss". The
-feed items are based on links in bullet lists using the asterix ("*").
-The items must point to local pages. This is why the link may not
-contain two forward slashes ("//").
+Every file can be viewed as feed by using the extension ".rss". The feed items
+are based on links in bullet lists using the asterix ("\*"). The items must
+point to local pages. This is why the link may not contain two forward slashes
+("//").
 
-Assume this is the index page. The feed would be "/view/index.rss". It
-would contain the pages "Arianism", "Donatism" and "Monophysitism" but
-it would not contain the pages "Feed" and "About" since the list items
-don't start with an asterix.
+Assume this is the index page. The feed would be "/view/index.rss". It would
+contain the pages "Arianism", "Donatism" and "Monophysitism" but it would not
+contain the pages "Feed" and "About" since the list items don't start with an
+asterix.
 
 ```
 # Main Page
@@ -115,28 +132,43 @@ The feed contains at most 10 items, starting at the top.
 
 # PERCENT ENCODING
 
-If you use Markdown links to local pages, you must percent-encode the
-link target. Any character that is not an "unreserved character"
-according to RFC 3986 might need to be encoded. The unreserved
-characters are a-z, A-Z, 0-9, as well as the four characters '-',
-'\_', '.' and '~'.
+If you use Markdown links to local pages, you must percent-encode the link
+target. Any character that is not an "unreserved character" according to RFC
+3986 might need to be encoded. The unreserved characters are a-z, A-Z, 0-9, as
+well as the four characters '-', '\_', '.' and '~'.
 
-Percent-encoding means that each character is converted into one or
-more bytes, and each byte is represented as a percent character
-followed by a hexadecimal representation.
+Percent-encoding means that each character is converted into one or more bytes,
+and each byte is represented as a percent character followed by a hexadecimal
+representation.
 
-Realistically, what probably works best is to use a browser. If you
-type "http://example.org/Alex Schröder" into the address bar, you'll
-get sent to the example domain. If you now copy the address and paste
-it back into a text editor, you'll get
-"http://example.org/Alex%20Schr%C3%B6der" and that's how you'll learn
-that the Space is encoded by %20 and that the character 'ö' is encoded
-by %C3%B6. To link to the page "Alex Schröder" you would write
-something like this: "[Alex](Alex%20Schr%C3%B6der)".
+Realistically, what probably works best is to use a browser. If you type
+"http://example.org/Alex Schröder" into the address bar, you'll get sent to the
+example domain. If you now copy the address and paste it back into a text
+editor, you'll get "http://example.org/Alex%20Schr%C3%B6der" and that's how
+you'll learn that the Space is encoded by %20 and that the character 'ö' is
+encoded by %C3%B6. To link to the page "Alex Schröder" you would write something
+like this: "[Alex](Alex%20Schr%C3%B6der)".
+
+Another thing that's common is that your page name contains a colon.
+This is legal. The URL parser might still reject it. If you run the
+"missing" subcommand, you'll get to see error: "first path segment in
+URL cannot contain colon". The solution is to prepend "./"!
+
+Example:
+
+```
+[2021-10-15 Re: Mark It Down](2021-10-15_Re:_Mark_It_Down)
+```
+
+Fixed:
+
+```
+[2021-10-15 Re: Mark It Down](./2021-10-15_Re:_Mark_It_Down)
+```
 
 # SEE ALSO
 
-_oddmu_(1)
+_oddmu_(1), _oddmu-missing_(1)
 
 This wiki uses the Go Markdown library.
 https://github.com/gomarkdown/markdown

man/oddmu.service.5

@@ -5,7 +5,7 @@
 .nh
 .ad l
 .\" Begin generated content:
-.TH "ODDMU.SERVICE" "5" "2023-09-21"
+.TH "ODDMU.SERVICE" "5" "2023-10-28"
 .PP
 .SH NAME
 .PP
@@ -13,12 +13,11 @@ oddmu.\&service - how to setup Oddmu using systemd
 .PP
 .SS DESCRIPTION
 .PP
-Here'\&s how to setup a wiki using systemd such that it starts
-automatically when the system boots and gets restarted automatically
-when it crashes.\&
+Here'\&s how to setup a wiki using systemd such that it starts automatically when
+the system boots and gets restarted automatically when it crashes.\&
 .PP
-First, create a new user called "oddmu" with it'\&s own home directory
-but without a login.\&
+First, create a new user called "oddmu" with it'\&s own home directory but without
+a login.\&
 .PP
 .nf
 .RS 4
@@ -26,15 +25,15 @@ adduser --system --home /home/oddmu oddmu
 .fi
 .RE
 .PP
-The directory "/home/oddmu" contains the templates and all the data
-files.\& Copy all the tempaltes files ending in ".\&html" from the source
-distribution to "/home/oddmu".\&
+The directory "/home/oddmu" contains the templates and all the data files.\& Copy
+all the templates files ending in ".\&html" from the source distribution to
+"/home/oddmu".\&
 .PP
-If you want to keep everything in one place, copy the binary "oddmu"
-and the service file "oddmu.\&service" to "/home/oddmu", too.\&
+If you want to keep everything in one place, copy the binary "oddmu" and the
+service file "oddmu.\&service" to "/home/oddmu", too.\&
 .PP
-Edit the `oddmu.\&service` file.\& These are the lines you most likely
-have to take care of:
+Edit the `oddmu.\&service` file.\& These are the lines you most likely have to take
+care of:
 .PP
 .nf
 .RS 4
@@ -54,8 +53,7 @@ systemctl enable --now oddmu
 .fi
 .RE
 .PP
-You should be able to visit the wiki at
-http://localhost:8080/.\&
+You should be able to visit the wiki at http://localhost:8080/.\&
 .PP
 Check the log:
 .PP
@@ -73,6 +71,15 @@ journalctl --follow --unit oddmu
 .fi
 .RE
 .PP
+For it to restart when the server reboots:
+.PP
+.nf
+.RS 4
+sudo ln -sf /home/oddmu/oddmu\&.service 
+  /etc/systemd/system/multi-user\&.target\&.wants/
+.fi
+.RE
+.PP
 .SH SEE ALSO
 .PP
 \fIoddmu\fR(1), \fIsystemd.\&exec\fR(5), \fIcapabilities\fR(7)

man/oddmu.service.5.txt

@@ -6,26 +6,25 @@ oddmu.service - how to setup Oddmu using systemd
 
 ## DESCRIPTION
 
-Here's how to setup a wiki using systemd such that it starts
-automatically when the system boots and gets restarted automatically
-when it crashes.
+Here's how to setup a wiki using systemd such that it starts automatically when
+the system boots and gets restarted automatically when it crashes.
 
-First, create a new user called "oddmu" with it's own home directory
-but without a login.
+First, create a new user called "oddmu" with it's own home directory but without
+a login.
 
 ```
 adduser --system --home /home/oddmu oddmu
 ```
 
-The directory "/home/oddmu" contains the templates and all the data
-files. Copy all the tempaltes files ending in ".html" from the source
-distribution to "/home/oddmu".
+The directory "/home/oddmu" contains the templates and all the data files. Copy
+all the templates files ending in ".html" from the source distribution to
+"/home/oddmu".
 
-If you want to keep everything in one place, copy the binary "oddmu"
-and the service file "oddmu.service" to "/home/oddmu", too.
+If you want to keep everything in one place, copy the binary "oddmu" and the
+service file "oddmu.service" to "/home/oddmu", too.
 
-Edit the `oddmu.service` file. These are the lines you most likely
-have to take care of:
+Edit the `oddmu.service` file. These are the lines you most likely have to take
+care of:
 
 ```
 ExecStart=/home/oddmu/oddmu
@@ -41,8 +40,7 @@ ln -s /home/oddmu/oddmu.service /etc/systemd/system/
 systemctl enable --now oddmu
 ```
 
-You should be able to visit the wiki at
-http://localhost:8080/.
+You should be able to visit the wiki at http://localhost:8080/.
 
 Check the log:
 
@@ -56,6 +54,13 @@ Follow the log:
 journalctl --follow --unit oddmu
 ```
 
+For it to restart when the server reboots:
+
+```
+sudo ln -sf /home/oddmu/oddmu.service \
+  /etc/systemd/system/multi-user.target.wants/
+```
+
 # SEE ALSO
 
 _oddmu_(1), _systemd.exec_(5), _capabilities_(7)

missing_cmd.go

@@ -0,0 +1,119 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"github.com/gomarkdown/markdown"
+	"github.com/gomarkdown/markdown/ast"
+	"github.com/google/subcommands"
+	"io"
+	"io/fs"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+type missingCmd struct {
+}
+
+func (*missingCmd) Name() string     { return "missing" }
+func (*missingCmd) Synopsis() string { return "list missing pages" }
+func (*missingCmd) Usage() string {
+	return `missing:
+  Listing pages with links to missing pages.
+`
+}
+
+func (cmd *missingCmd) SetFlags(f *flag.FlagSet) {
+}
+
+func (cmd *missingCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
+	return missingCli(os.Stdout, f.Args())
+}
+
+func missingCli(w io.Writer, args []string) subcommands.ExitStatus {
+	names := make(map[string]bool)
+	err := filepath.Walk(".", func(path string, info fs.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		filename := path
+		if info.IsDir() || strings.HasPrefix(filename, ".") {
+			return nil
+		}
+		if strings.HasSuffix(filename, ".md") {
+			name := strings.TrimSuffix(filename, ".md")
+			names[name] = true
+		} else {
+			names[filename] = false
+		}
+		return nil
+	})
+	if err != nil {
+		fmt.Fprintln(w, err)
+		return subcommands.ExitFailure
+	}
+	found := false
+	for name, isPage := range names {
+		if !isPage {
+			continue
+		}
+		p, err := loadPage(name)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Loading %s: %s\n", name, err)
+			return subcommands.ExitFailure
+		}
+		for _, link := range p.links() {
+			u, err := url.Parse(link)
+			if err != nil {
+				fmt.Fprintln(os.Stderr, name, err)
+				return subcommands.ExitFailure
+			}
+			if u.Scheme == "" && u.Path != "" && !strings.HasPrefix(u.Path, "/") {
+				// feeds can work if the matching page works
+				u.Path = strings.TrimSuffix(u.Path, ".rss")
+				// links to the source file can work
+				u.Path = strings.TrimSuffix(u.Path, ".md")
+				// pages containing a colon need the ./ prefix
+				u.Path = strings.TrimPrefix(u.Path, "./")
+				// check whether the destinatino is a known page
+				destination, err := url.PathUnescape(u.Path)
+				if err != nil {
+					fmt.Fprintf(os.Stderr, "Cannot decode %s: %s\n", link, err)
+					return subcommands.ExitFailure
+				}
+				_, ok := names[destination]
+				if !ok {
+					if !found {
+						fmt.Fprintln(w, "Page\tMissing")
+						found = true
+					}
+					fmt.Fprintf(w, "%s\t%s\n", name, link)
+				}
+			}
+		}
+	}
+	if !found {
+		fmt.Fprintln(w, "No missing pages found.")
+	}
+	return subcommands.ExitSuccess
+}
+
+// links parses the page content and returns an array of link destinations.
+func (p *Page) links() []string {
+	var links []string
+	parser, _ := wikiParser()
+	doc := markdown.Parse(p.Body, parser)
+	ast.WalkFunc(doc, func(node ast.Node, entering bool) ast.WalkStatus {
+		if entering {
+			switch v := node.(type) {
+			case *ast.Link:
+				links = append(links, string(v.Destination))
+			}
+		}
+		return ast.GoToNext
+	})
+	return links
+}

missing_cmd_test.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"bytes"
+	"github.com/google/subcommands"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestMissingCmd(t *testing.T) {
+	b := new(bytes.Buffer)
+	s := missingCli(b, nil)
+	assert.Equal(t, subcommands.ExitSuccess, s)
+	r := `Page	Missing
+index	test
+`
+	assert.Equal(t, r, b.String())
+}

notify_cmd.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"github.com/google/subcommands"
+	"io"
+	"os"
+)
+
+type notifyCmd struct {
+}
+
+func (*notifyCmd) Name() string     { return "notify" }
+func (*notifyCmd) Synopsis() string { return "add links to changes.md, index.md, and hashtag pages" }
+func (*notifyCmd) Usage() string {
+	return `notify <page name> ...:
+  For each page, add entries to changes.md, index.md, and hashtag pages.
+  This is useful when writing pages offline and replicates the behaviour
+  triggered by the "Add link to the list of changes" checkbox, online.
+`
+}
+
+func (cmd *notifyCmd) SetFlags(f *flag.FlagSet) {
+}
+
+func (cmd *notifyCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
+	return notifyCli(os.Stdout, f.Args())
+}
+
+func notifyCli(w io.Writer, args []string) subcommands.ExitStatus {
+	index.load()
+	for _, name := range args {
+		p, err := loadPage(name)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Loading %s: %s\n", name, err)
+			return subcommands.ExitFailure
+		}
+		err = p.notify()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%s: %s\n", name, err)
+			return subcommands.ExitFailure
+		}
+	}
+	return subcommands.ExitSuccess
+}

page.go

@@ -2,13 +2,16 @@ package main
 
 import (
 	"bytes"
-	"fmt"
 	"github.com/microcosm-cc/bluemonday"
 	"html/template"
+	"log"
 	"net/url"
 	"os"
+	"path"
 	"path/filepath"
+	"regexp"
 	"strings"
+	"time"
 )
 
 // Page is a struct containing information about a single page. Title
@@ -27,17 +30,21 @@ type Page struct {
 	Hashtags []string
 }
 
-// santize uses bluemonday to sanitize the HTML.
-// No exceptions are made because this is used for snippets.
+var blogRe = regexp.MustCompile(`^\d\d\d\d-\d\d-\d\d`)
+
+// santizeStrict uses bluemonday to sanitize the HTML away. No elements are allowed except for the b tag because this is
+// used for snippets.
 func sanitizeStrict(s string) template.HTML {
-	return template.HTML(bluemonday.StrictPolicy().Sanitize(s))
+	policy := bluemonday.StrictPolicy()
+	policy.AllowElements("b")
+	return template.HTML(policy.Sanitize(s))
 }
 
-// santizeBytes uses bluemonday to sanitize the HTML.
-func sanitizeBytes(bytes []byte) template.HTML {
-	policy := bluemonday.UGCPolicy()
-	policy.AllowAttrs("class").OnElements("a") // for hashtags
-	return template.HTML(policy.SanitizeBytes(bytes))
+// unsafeBytes does not use bluemonday to sanitize the HTML used for pages. This is where you make changes if you want
+// to be more lenient. If you look at the git repository, there are older versions containing the function sanitizeBytes
+// which would do elaborate checking.
+func unsafeBytes(bytes []byte) template.HTML {
+	return template.HTML(bytes)
 }
 
 // nameEscape returns the page name safe for use in URLs. That is,
@@ -60,8 +67,8 @@ func (p *Page) save() error {
 	filename := p.Name + ".md"
 	s := bytes.ReplaceAll(p.Body, []byte{'\r'}, []byte{})
 	if len(s) == 0 {
-		_ = os.Rename(filename, filename+"~")
-		return os.Remove(filename)
+		p.removeFromIndex()
+		return os.Rename(filename, filename+"~")
 	}
 	p.Body = s
 	p.updateIndex()
@@ -69,14 +76,26 @@ func (p *Page) save() error {
 	if d != "." {
 		err := os.MkdirAll(d, 0755)
 		if err != nil {
-			fmt.Printf("Creating directory %s failed", d)
+			log.Printf("Creating directory %s failed: %s", d, err)
 			return err
 		}
 	}
-	_ = os.Rename(filename, filename+"~")
+	backup(filename)
 	return os.WriteFile(filename, s, 0644)
 }
 
+// backup a file by renaming (!) it unless the existing backup is less than an hour old. A backup gets a tilde appended
+// to it ("~"). This is true even if the file refers to a binary file like "image.png" and most applications don't know
+// what to do with a file called "image.png~".
+func backup(filename string) error {
+	backup := filename + "~"
+	fi, err := os.Stat(backup)
+	if err != nil || time.Since(fi.ModTime()).Minutes() >= 60 {
+		return os.Rename(filename, backup)
+	}
+	return nil
+}
+
 // loadPage loads a Page given a name. The filename loaded is that
 // Page.Name with the ".md" extension. The Page.Title is set to the
 // Page.Name (and possibly changed, later). The Page.Body is set to
@@ -91,9 +110,9 @@ func loadPage(name string) (*Page, error) {
 	return &Page{Title: name, Name: name, Body: body, Language: ""}, nil
 }
 
-// handleTitle extracts the title from a Page and sets Page.Title, if
-// any. If replace is true, the page title is also removed from
-// Page.Body. Make sure not to save this! This is only for rendering.
+// handleTitle extracts the title from a Page and sets Page.Title, if any. If replace is true, the page title is also
+// removed from Page.Body. Make sure not to save this! This is only for rendering. In a template, the title is a
+// separate attribute and is not repeated in the HTML.
 func (p *Page) handleTitle(replace bool) {
 	s := string(p.Body)
 	m := titleRegexp.FindStringSubmatch(s)
@@ -119,10 +138,23 @@ func (p *Page) summarize(q string) {
 	p.Language = language(t)
 }
 
+// isBlog returns true if the page name starts with an ISO date
+func (p *Page) isBlog() bool {
+	name := path.Base(p.Name)
+	return blogRe.MatchString(name)
+}
+
+// Dir returns the directory the page is in. It's either the empty string if the page is in the Oddmu working directory,
+// or it ends in a slash. This is used to create the upload link in "view.html", for example.
 func (p *Page) Dir() string {
 	d := filepath.Dir(p.Name)
 	if d == "." {
 		return ""
 	}
-	return d
+	return d + "/"
+}
+
+// Today returns the date, as a string, for use in templates.
+func (p *Page) Today() string {
+	return time.Now().Format(time.DateOnly)
 }

page_test.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"github.com/stretchr/testify/assert"
-	"os"
 	"regexp"
 	"testing"
 )
@@ -19,30 +18,25 @@ But yearn for blue sky`)}
 	assert.Regexp(t, regexp.MustCompile("^My back"), string(p.Body))
 }
 
-// wipes testdata
 func TestPageDir(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/dir")
 	index.load()
-	p := &Page{Name: "testdata/moon", Body: []byte(`# Moon
+	p := &Page{Name: "testdata/dir/moon", Body: []byte(`# Moon
 From bed to bathroom
 A slow shuffle in the dark
 Moonlight floods the aisle`)}
 	p.save()
 
-	o, err := loadPage("testdata/moon")
+	o, err := loadPage("testdata/dir/moon")
 	assert.NoError(t, err, "load page")
 	assert.Equal(t, p.Body, o.Body)
-	assert.FileExists(t, "testdata/moon.md")
+	assert.FileExists(t, "testdata/dir/moon.md")
 
 	// Saving an empty page deletes it.
-	p = &Page{Name: "testdata/moon", Body: []byte("")}
+	p = &Page{Name: "testdata/dir/moon", Body: []byte("")}
 	p.save()
-	assert.NoFileExists(t, "testdata/moon.md")
+	assert.NoFileExists(t, "testdata/dir/moon.md")
 
 	// But the backup still exists.
-	assert.FileExists(t, "testdata/moon.md~")
-
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+	assert.FileExists(t, "testdata/dir/moon.md~")
 }

parser.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"github.com/gomarkdown/markdown"
 	"github.com/gomarkdown/markdown/ast"
+	"github.com/gomarkdown/markdown/html"
 	"github.com/gomarkdown/markdown/parser"
 	"net/url"
 )
@@ -35,7 +36,7 @@ func wikiLink(p *parser.Parser, fn func(p *parser.Parser, data []byte, offset in
 // hashtag returns an inline parser function. This indirection is
 // required because we want to receive an array of hashtags found.
 func hashtag() (func(p *parser.Parser, data []byte, offset int) (int, ast.Node), *[]string) {
-	hashtags := make([]string,0)
+	hashtags := make([]string, 0)
 	return func(p *parser.Parser, data []byte, offset int) (int, ast.Node) {
 		data = data[offset:]
 		i := 0
@@ -49,8 +50,7 @@ func hashtag() (func(p *parser.Parser, data []byte, offset int) (int, ast.Node),
 		hashtags = append(hashtags, string(data[1:i]))
 		link := &ast.Link{
 			AdditionalAttributes: []string{`class="tag"`},
-			Destination: append([]byte("/search?q=%23"), data[1:i]...),
-			Title:       data[0:i],
+			Destination:          append([]byte("/search/?q=%23"), data[1:i]...),
 		}
 		text := bytes.ReplaceAll(data[0:i], []byte("_"), []byte(" "))
 		ast.AppendChild(link, &ast.Text{Leaf: ast.Leaf{Literal: text}})
@@ -58,10 +58,11 @@ func hashtag() (func(p *parser.Parser, data []byte, offset int) (int, ast.Node),
 	}, &hashtags
 }
 
-// renderHtml renders the Page.Body to HTML and sets Page.Html,
-// Page.Language, Page.Hashtags, and escapes Page.Name.
-func (p *Page) renderHtml() {
-	parser := parser.New()
+// wikiParser returns a parser with the Oddmu specific changes. Specifically: [[wiki links]], #hash_tags,
+// @webfinger@accounts. It also uses the CommonExtensions and Block Attributes, and no MathJax ($).
+func wikiParser() (*parser.Parser, *[]string) {
+	extensions := (parser.CommonExtensions | parser.Attributes) & ^parser.MathJax
+	parser := parser.NewWithExtensions(extensions)
 	prev := parser.RegisterInline('[', nil)
 	parser.RegisterInline('[', wikiLink(parser, prev))
 	fn, hashtags := hashtag()
@@ -69,9 +70,26 @@ func (p *Page) renderHtml() {
 	if useWebfinger {
 		parser.RegisterInline('@', account)
 	}
-	maybeUnsafeHTML := markdown.ToHTML(p.Body, parser, nil)
+	return parser, hashtags
+}
+
+// wikiRenderer is a Renderer for Markdown that adds lazy loading of images. This in turn requires an exception for the
+// sanitization policy!
+func wikiRenderer() *html.Renderer {
+	htmlFlags := html.CommonFlags | html.LazyLoadImages
+	opts := html.RendererOptions{Flags: htmlFlags}
+	renderer := html.NewRenderer(opts)
+	return renderer
+}
+
+// renderHtml renders the Page.Body to HTML and sets Page.Html, Page.Language, Page.Hashtags, and escapes Page.Name.
+// Note: If the rendered HTML doesn't contain the attributes or elements you expect it to contain, check sanitizeBytes!
+func (p *Page) renderHtml() {
+	parser, hashtags := wikiParser()
+	renderer := wikiRenderer()
+	maybeUnsafeHTML := markdown.ToHTML(p.Body, parser, renderer)
 	p.Name = nameEscape(p.Name)
-	p.Html = sanitizeBytes(maybeUnsafeHTML)
+	p.Html = unsafeBytes(maybeUnsafeHTML)
 	p.Language = language(p.plainText())
 	p.Hashtags = *hashtags
 }

parser_test.go

@@ -43,7 +43,7 @@ I am cold, alone
 Too faint to focus, so far
 I am cold, alone</p>
 
-<p><a class="tag" href="/search?q=%23Haiku" rel="nofollow">#Haiku</a> <a class="tag" href="/search?q=%23Cold_Poets" rel="nofollow">#Cold Poets</a></p>
+<p><a class="tag" href="/search/?q=%23Haiku">#Haiku</a> <a class="tag" href="/search/?q=%23Cold_Poets">#Cold Poets</a></p>
 `
 	assert.Equal(t, r, string(p.Html))
 }
@@ -57,8 +57,29 @@ Our [[time together]]`)}
 	r := `<h1>Photos and Books</h1>
 
 <p>Blue and green and black
-Sky and grass and <a href="cliffs" rel="nofollow">ragged cliffs</a>
-Our <a href="time%20together" rel="nofollow">time together</a></p>
+Sky and grass and <a href="cliffs">ragged cliffs</a>
+Our <a href="time%20together">time together</a></p>
 `
 	assert.Equal(t, r, string(p.Html))
 }
+
+func TestPageHtmlDollar(t *testing.T) {
+	p := &Page{Body: []byte(`# No $dollar$ can buy this
+Dragonfly hovers
+darts chases turns lands and rests
+A mighty jewel`)}
+	p.renderHtml()
+	r := `<h1>No $dollar$ can buy this</h1>
+
+<p>Dragonfly hovers
+darts chases turns lands and rests
+A mighty jewel</p>
+`
+	assert.Equal(t, r, string(p.Html))
+}
+
+func TestLazyLoadImages(t *testing.T) {
+	p := &Page{Body: []byte(`![](test.jpg)`)}
+	p.renderHtml()
+	assert.Contains(t, string(p.Html), "lazy")
+}

replace_cmd.go

@@ -19,32 +19,40 @@ import (
 
 type replaceCmd struct {
 	confirm bool
+	regexp  bool
 }
 
 func (cmd *replaceCmd) SetFlags(f *flag.FlagSet) {
 	f.BoolVar(&cmd.confirm, "confirm", false, "do the replacement instead of just doing a dry run")
+	f.BoolVar(&cmd.regexp, "regexp", false, "the search string is a regular expression")
 }
 
 func (*replaceCmd) Name() string     { return "replace" }
-func (*replaceCmd) Synopsis() string { return "Search and replace a regular expression." }
+func (*replaceCmd) Synopsis() string { return "search and replace in all the pages" }
 func (*replaceCmd) Usage() string {
-	return `replace [-confirm] <regexp> <replacement>:
-  Search a regular expression and replace it. By default, this is a
-  dry run and nothing is saved. The replacement can use $1, $2, etc.
-  to refer to capture groups in the regular expression.
+	return `replace [-confirm] [-regexp] <term> <replacement>:
+  Search a string or a regular expression and replace it. By default,
+  this is a dry run and nothing is saved. If this is a regular
+  expression, the replacement can use $1, $2, etc. to refer to capture
+  groups in the regular expression.
 `
 }
 
 func (cmd *replaceCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
-	return replaceCli(os.Stdout, cmd.confirm, f.Args())
+	return replaceCli(os.Stdout, cmd.confirm, cmd.regexp, f.Args())
 }
 
-func replaceCli(w io.Writer, confirm bool, args []string) subcommands.ExitStatus {
+func replaceCli(w io.Writer, isConfirmed bool, isRegexp bool, args []string) subcommands.ExitStatus {
 	if len(args) != 2 {
-		fmt.Fprintln(w, "Replace takes exactly two arguments.")
+		fmt.Fprintln(os.Stderr, "Replace takes exactly two arguments.")
 		return subcommands.ExitFailure
 	}
-	re := regexp.MustCompile(args[0])
+	var re *regexp.Regexp
+	if isRegexp {
+		re = regexp.MustCompile(args[0])
+	} else {
+		re = regexp.MustCompile(regexp.QuoteMeta(args[0]))
+	}
 	repl := []byte(args[1])
 	changes := 0
 	err := filepath.Walk(".", func(path string, info fs.FileInfo, err error) error {
@@ -61,7 +69,7 @@ func replaceCli(w io.Writer, confirm bool, args []string) subcommands.ExitStatus
 		result := re.ReplaceAll(body, repl)
 		if !slices.Equal(result, body) {
 			changes++
-			if confirm {
+			if isConfirmed {
 				fmt.Fprintln(w, path)
 				_ = os.Rename(path, path+"~")
 				err = os.WriteFile(path, result, 0644)
@@ -77,15 +85,23 @@ func replaceCli(w io.Writer, confirm bool, args []string) subcommands.ExitStatus
 		return nil
 	})
 	if err != nil {
-		fmt.Fprintln(w, err)
+		fmt.Fprintln(os.Stderr, err)
 		return subcommands.ExitFailure
 	}
 	if changes == 1 {
-		fmt.Fprintln(w, "1 change was made.")
+		if isConfirmed {
+			fmt.Fprintln(w, "1 file was changed.")
+		} else {
+			fmt.Fprintln(w, "1 file would be changed.")
+		}
 	} else {
-		fmt.Fprintf(w, "%d changes were made.\n", changes)
+		if isConfirmed {
+			fmt.Fprintf(w, "%d files were changed.\n", changes)
+		} else {
+			fmt.Fprintf(w, "%d files would be changed.\n", changes)
+		}
 	}
-	if !confirm && changes > 0 {
+	if !isConfirmed && changes > 0 {
 		fmt.Fprintln(w, "This is a dry run. Use -confirm to make it happen.")
 	}
 	return subcommands.ExitSuccess

replace_cmd_test.go

@@ -2,24 +2,22 @@ package main
 
 import (
 	"bytes"
-	"github.com/stretchr/testify/assert"
 	"github.com/google/subcommands"
-	"os"
+	"github.com/stretchr/testify/assert"
 	"testing"
 )
 
-// wipes testdata
 func TestReplaceCmd(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/replace")
 	index.load()
-	p := &Page{Name: "testdata/pluto", Body: []byte(`# Pluto
+	p := &Page{Name: "testdata/replace/pluto", Body: []byte(`# Pluto
 Out there is a rock
 And more rocks uncountable
 You are no planet`)}
 	p.save()
 
-	r := `--- testdata/pluto.md~
-+++ testdata/pluto.md
+	r := `--- testdata/replace/pluto.md~
++++ testdata/replace/pluto.md
 @@ -1,4 +1,4 @@
  # Pluto
  Out there is a rock
@@ -29,16 +27,12 @@ You are no planet`)}
 +You are planetoid
 \ No newline at end of file
 
-1 change was made.
+1 file would be changed.
 This is a dry run. Use -confirm to make it happen.
 `
-	
+
 	b := new(bytes.Buffer)
-	s := replaceCli(b, false, []string{`\bno planet`, `planetoid`})
+	s := replaceCli(b, false, true, []string{`\bno planet`, `planetoid`})
 	assert.Equal(t, subcommands.ExitSuccess, s)
 	assert.Equal(t, r, b.String())
-
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
 }

score.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"regexp"
-	"strings"
 )
 
 // score splits the query string q into terms and scores the text
@@ -10,7 +9,7 @@ import (
 // characters quoted.
 func score(q string, s string) int {
 	score := 0
-	re, err := regexp.Compile("(?i)" + q)
+	re, err := regexp.Compile("(?i)" + regexp.QuoteMeta(q))
 	if err == nil {
 		m := re.FindAllString(s, -1)
 		if m != nil {
@@ -18,8 +17,8 @@ func score(q string, s string) int {
 			score += len(m)
 		}
 	}
-	for _, v := range strings.Fields(q) {
-		re, err := regexp.Compile(`(?is)(\pL?)(` + v + `)(\pL?)`)
+	for _, token := range highlightTokens(q) {
+		re, err := regexp.Compile(`(?is)(\pL?)(` + regexp.QuoteMeta(token) + `)(\pL?)`)
 		if err != nil {
 			continue
 		}

search.go

@@ -1,8 +1,10 @@
 package main
 
 import (
-	"fmt"
+	"log"
 	"net/http"
+	"path"
+	"regexp"
 	"slices"
 	"strconv"
 	"strings"
@@ -16,11 +18,11 @@ import (
 // a search result, Body and Html are simple extracts.
 type Search struct {
 	Query    string
+	Dir      string
 	Items    []*Page
 	Previous int
 	Page     int
 	Next     int
-	Last     int
 	More     bool
 	Results  bool
 }
@@ -29,28 +31,41 @@ type Search struct {
 // whether the query string matches the page title; 2. descending if
 // the page titles start with a digit; 3. otherwise ascending.
 // Access to the index requires a read lock!
-func sortNames(q string) func(a, b string) int {
+func sortNames(tokens []string) func(a, b string) int {
 	return func(a, b string) int {
 		// If only one page contains the query string, it
 		// takes precedence.
-		ia := strings.Contains(index.titles[a], q)
-		ib := strings.Contains(index.titles[b], q)
+		ia := false
+		ib := false
+		for _, token := range tokens {
+			if !ia && strings.Contains(index.titles[a], token) {
+				ia = true
+			}
+			if !ib && strings.Contains(index.titles[b], token) {
+				ib = true
+			}
+		}
 		if ia && !ib {
 			return -1
 		} else if !ia && ib {
 			return 1
 		}
-		// If both page names start with a number (like an ISO date),
-		// sort descending.
+		// Page names starting with a number come first. If
+		// both page names start with a number (like an ISO
+		// date), sort by page name, descending.
 		ra, _ := utf8.DecodeRuneInString(a)
+		na := unicode.IsNumber(ra)
 		rb, _ := utf8.DecodeRuneInString(b)
-		if unicode.IsNumber(ra) && unicode.IsNumber(rb) {
+		nb := unicode.IsNumber(rb)
+		if na && !nb {
+			return -1
+		} else if !na && nb {
+			return 1
+		} else if na && nb {
 			if a < b {
 				return 1
 			} else if a > b {
 				return -1
-			} else {
-				return 0
 			}
 		}
 		// Otherwise sort by title, ascending.
@@ -58,68 +73,170 @@ func sortNames(q string) func(a, b string) int {
 			return -1
 		} else if index.titles[a] > index.titles[b] {
 			return 1
-		} else {
-			return 0
 		}
-	}
-}
-
-// load the pages named.
-func load(names []string) []*Page {
-	items := make([]*Page, len(names))
-	for i, name := range names {
-		p, err := loadPage(name)
-		if err != nil {
-			fmt.Printf("Error loading %s\n", name)
-		} else {
-			items[i] = p
+		// Either the titles are equal or the index isn't
+		// initialized.
+		if a < b {
+			return -1
+		} else if a > b {
+			return 1
 		}
+		return 0
 	}
-	return items
 }
 
 // itemsPerPage says how many items to print on a page of search
 // results.
 const itemsPerPage = 20
 
-// search returns a sorted []Page where each page contains an extract
-// of the actual Page.Body in its Page.Html. Page size is 20. The
-// boolean return value indicates whether there are more results.
-func search(q string, page int) ([]*Page, bool, int) {
+// search returns a sorted []Page where each page contains an extract of the actual Page.Body in its Page.Html. Page
+// size is 20. Specify either the page number to return, or that all the results should be returned. Only ask for all
+// results if runtime is not an issue, like on the command line. The boolean return value indicates whether there are
+// more results.
+func search(q string, dir string, page int, all bool) ([]*Page, bool) {
 	if len(q) == 0 {
-		return make([]*Page, 0), false, 0
+		return make([]*Page, 0), false
 	}
-	index.RLock()
-	names := searchDocuments(q)
-	slices.SortFunc(names, sortNames(q))
-	index.RUnlock()
+	names := index.search(q) // hashtags or all names
+	names = filterPrefix(names, dir)
+	predicates, terms := predicatesAndTokens(q)
+	names = filterNames(names, predicates)
+	slices.SortFunc(names, sortNames(terms))
+	names, keepFirst := prependQueryPage(names, dir, q)
 	from := itemsPerPage * (page - 1)
-	if from > len(names) {
-		return make([]*Page, 0), false, 0
-	}
-	to := from + itemsPerPage
-	if to > len(names) {
-		to = len(names)
-	}
-	items := load(names[from:to])
+	to := from + itemsPerPage - 1
+	items, more := grep(terms, names, from, to, all, keepFirst)
 	for _, p := range items {
 		p.score(q)
 		p.summarize(q)
 	}
-	return items, to < len(names), len(names)/itemsPerPage + 1
+	return items, more
+}
+
+// filterPrefix filters the names by prefix. A prefix of "." means
+// that all the names are returned, since this is what path.Dir
+// returns for "no directory".
+func filterPrefix(names []string, prefix string) []string {
+	if prefix == "." {
+		return names
+	}
+	r := make([]string, 0)
+	for _, name := range names {
+		if strings.HasPrefix(name, prefix) {
+			r = append(r, name)
+		}
+	}
+	return r
+}
+
+// filterNames filters the names by all the predicats such as
+// "title:foo" or "blog:true".
+func filterNames(names, predicates []string) []string {
+	if len(predicates) == 0 {
+		return names
+	}
+	// the intersection requires sorted lists
+	slices.Sort(names)
+	index.RLock()
+	defer index.RUnlock()
+	for _, predicate := range predicates {
+		r := make([]string, 0)
+		if strings.HasPrefix(predicate, "title:") {
+			token := predicate[6:]
+			for _, name := range names {
+				if strings.Contains(strings.ToLower(index.titles[name]), token) {
+					r = append(r, name)
+				}
+			}
+		} else if predicate == "blog:true" || predicate == "blog:false" {
+			blog := predicate == "blog:true"
+			re := regexp.MustCompile(`(^|/)\d\d\d\d-\d\d-\d\d`)
+			for _, name := range names {
+				match := re.MatchString(name)
+				if blog && match || !blog && !match {
+					r = append(r, name)
+				}
+			}
+		} else {
+			log.Printf("Unsupported predicate: %s", predicate)
+		}
+		names = intersection(names, r)
+	}
+	return names
+}
+
+// grep searches the files for matches to all the tokens. It returns just a single page of results based [from:to-1] and
+// returns if there are more results. The all parameter ignores pagination (the from and to parameters). The keepFirst
+// parameter keeps the first page in the list, even if there is no match. This is used for hashtag pages.
+func grep(tokens, names []string, from, to int, all, keepFirst bool) ([]*Page, bool) {
+	pages := make([]*Page, 0)
+	i := 0
+NameLoop:
+	for n, name := range names {
+		p, err := loadPage(name)
+		if err != nil {
+			log.Printf("grep: cannot load %s: %s", name, err)
+			continue NameLoop
+		}
+		if n != 0 || !keepFirst {
+			body := strings.ToLower(string(p.Body))
+			for _, token := range tokens {
+				if !strings.Contains(body, token) {
+					continue NameLoop
+				}
+			}
+		}
+		i++
+		if all || i > from {
+			pages = append(pages, p)
+		}
+		if !all && i > to {
+			return pages, true
+		}
+	}
+	return pages, false
+}
+
+// prependQueryPage prepends the query itself, if a matching page name exists. This helps if people remember the name
+// exactly, or if searching for a hashtag. This function assumes that q is not the empty string. Return wether a page
+// was prepended or not.
+func prependQueryPage(names []string, dir, q string) ([]string, bool) {
+	index.RLock()
+	defer index.RUnlock()
+	if q[0] == '#' && !strings.Contains(q[1:], "#") {
+		q = q[1:]
+	}
+	q = path.Join(dir, q)
+	// if q exists in names, move it to the front
+	i := slices.Index(names, q)
+	if i == 0 {
+		return names, false
+	} else if i != -1 {
+		r := []string{q}
+		r = append(r, names[0:i]...)
+		r = append(r, names[i+1:]...)
+		return r, false
+	}
+	// otherwise, if q is a known page name, prepend it
+	_, ok := index.titles[q]
+	if ok {
+		return append([]string{q}, names...), true
+	}
+	return names, false
 }
 
 // searchHandler presents a search result. It uses the query string in
 // the form parameter "q" and the template "search.html". For each
 // page found, the HTML is just an extract of the actual body.
-func searchHandler(w http.ResponseWriter, r *http.Request) {
+// Search is limited to a directory and its subdirectories.
+func searchHandler(w http.ResponseWriter, r *http.Request, dir string) {
 	q := r.FormValue("q")
 	page, err := strconv.Atoi(r.FormValue("page"))
 	if err != nil {
 		page = 1
 	}
-	items, more, last := search(q, page)
-	s := &Search{Query: q, Items: items, Previous: page - 1, Page: page, Next: page + 1, Last: last,
+	items, more := search(q, dir, page, false)
+	s := &Search{Query: q, Dir: dir, Items: items, Previous: page - 1, Page: page, Next: page + 1,
 		Results: len(items) > 0, More: more}
 	renderTemplate(w, "search", s)
 }

search.html

@@ -6,12 +6,12 @@
     <meta name="viewport" content="width=device-width">
     <title>Search for {{.Query}}</title>
     <style>
-html { max-width: 65ch; padding: 2ch; margin: auto; color: #111; background: #ffe; }
+html { max-width: 65ch; padding: 2ch; margin: auto; color: #111; background-color: #ffe; }
 body { hyphens: auto; }
 header a { margin-right: 1ch; }
 form { display: inline-block; }
 input#search { width: 20ch; }
-button { background: #eee; color: inherit; border-radius: 4px; border-width: 1px; }
+button { background-color: #eee; color: inherit; border-radius: 4px; border-width: 1px; }
 img { max-width: 20%; }
 .result { font-size: larger }
 .score { font-size: smaller; opacity: 0.8; }
@@ -21,9 +21,9 @@ img { max-width: 20%; }
     <header>
       <a href="#main">Skip navigation</a>
       <a href="/view/index">Home</a>
-      <form role="search" action="/search" method="GET">
+      <form role="search" action="/search/{{.Dir}}" method="GET">
         <label for="search">Search:</label>
-        <input id="search" type="text" value="{{.Query}}" spellcheck="false" name="q" accesskey="f" required>
+        <input id="search" type="text" value="{{.Query}}" spellcheck="false" name="q" accesskey="f" placeholder="term #tag title:term blog:true" required>
         <button>Go</button>
       </form>
     </header>
@@ -31,11 +31,10 @@ img { max-width: 20%; }
       <h1>Search for {{.Query}}</h1>
       {{if .Results}}
       <p>
-        {{if gt .Page 2}}<a href="/search?q={{.Query}}&page=1">First</a>{{end}}
-        {{if gt .Page 1}}<a href="/search?q={{.Query}}&page={{.Previous}}">Previous</a>{{end}}
+        {{if gt .Page 2}}<a href="/search/{{.Dir}}?q={{.Query}}&page=1">First</a>{{end}}
+        {{if gt .Page 1}}<a href="/search/{{.Dir}}?q={{.Query}}&page={{.Previous}}">Previous</a>{{end}}
         Page {{.Page}}
-        {{if .More}}<a href="/search?q={{.Query}}&page={{.Next}}">Next</a>{{end}}
-        {{if lt .Next .Last}}<a href="/search?q={{.Query}}&page={{.Last}}">Last</a>{{end}}
+        {{if .More}}<a href="/search/{{.Dir}}?q={{.Query}}&page={{.Next}}">Next</a>{{end}}
       {{range .Items}}
       <article lang="{{.Language}}">
         <p><a class="result" href="/view/{{.Name}}">{{.Title}}</a>
@@ -44,11 +43,10 @@ img { max-width: 20%; }
       </article>
       {{end}}
       <p>
-        {{if gt .Page 2}}<a href="/search?q={{.Query}}&page=1">First</a>{{end}}
-        {{if gt .Page 1}}<a href="/search?q={{.Query}}&page={{.Previous}}">Previous</a>{{end}}
+        {{if gt .Page 2}}<a href="/search/{{.Dir}}?q={{.Query}}&page=1">First</a>{{end}}
+        {{if gt .Page 1}}<a href="/search/{{.Dir}}?q={{.Query}}&page={{.Previous}}">Previous</a>{{end}}
         Page {{.Page}}
-        {{if .More}}<a href="/search?q={{.Query}}&page={{.Next}}">Next</a>{{end}}
-        {{if lt .Next .Last}}<a href="/search?q={{.Query}}&page={{.Last}}">Last</a>{{end}}
+        {{if .More}}<a href="/search/{{.Dir}}?q={{.Query}}&page={{.Next}}">Next</a>{{end}}
       {{else}}
       <p>No results.</p>
       {{end}}

search_cmd.go

@@ -4,17 +4,24 @@ import (
 	"context"
 	"flag"
 	"fmt"
+	"github.com/charmbracelet/lipgloss"
 	"github.com/google/subcommands"
 	"io"
 	"os"
+	"regexp"
+	"strings"
 )
 
 type searchCmd struct {
-	page int
+	page    int
+	all     bool
+	extract bool
 }
 
 func (cmd *searchCmd) SetFlags(f *flag.FlagSet) {
-	f.IntVar(&cmd.page, "page", 1, "the page in the search result set")
+	f.IntVar(&cmd.page, "page", 1, "the page in the search result set, default 1")
+	f.BoolVar(&cmd.all, "all", false, "show all the pages and ignore -page")
+	f.BoolVar(&cmd.extract, "extract", false, "print page extract instead of link list")
 }
 
 func (*searchCmd) Name() string     { return "search" }
@@ -23,32 +30,58 @@ func (*searchCmd) Usage() string {
 	return `search [-page <n>] <terms>:
   Search for pages matching terms and print the result set as a
   Markdown list. Before searching, all the pages are indexed. Thus,
-  startup is slow. The benefit is that the page order and scores are
-  exactly as when the wiki runs.
+  startup is slow. The benefit is that the page order is exactly as
+  when the wiki runs.
 `
 }
 
 func (cmd *searchCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
-	return searchCli(os.Stdout, cmd.page, f.Args())
+	return searchCli(os.Stdout, cmd.page, cmd.all, cmd.extract, false, f.Args())
 }
 
 // searchCli runs the search command on the command line. It is used
 // here with an io.Writer for easy testing.
-func searchCli(w io.Writer, n int, args []string) subcommands.ExitStatus {
+func searchCli(w io.Writer, n int, all, extract bool, quiet bool, args []string) subcommands.ExitStatus {
 	index.load()
-	for _, q := range args {
-		items, more, _ := search(q, n)
+	q := strings.Join(args, " ")
+	items, more := search(q, ".", n, true)
+	if !quiet {
+		fmt.Fprint(os.Stderr, "Search for ", q)
+		if !all {
+			fmt.Fprint(os.Stderr, ", page ", n)
+		}
+		fmt.Fprint(os.Stderr, ": ", len(items))
 		if len(items) == 1 {
-			fmt.Fprintf(w, "Search for %s, page %d: 1 result\n", q, n)
+			fmt.Fprint(os.Stderr, " result\n")
 		} else {
-			fmt.Fprintf(w, "Search for %s, page %d: %d results\n", q, n, len(items))
+			fmt.Fprint(os.Stderr, " results\n")
 		}
+	}
+	if extract {
+		searchExtract(w, items)
+	} else {
 		for _, p := range items {
-			fmt.Fprintf(w, "* [%s](%s) (%d)\n", p.Title, p.Name, p.Score)
-		}
-		if more {
-			fmt.Fprintf(w, "There are more results\n")
+			fmt.Fprintf(w, "* [%s](%s)\n", p.Title, p.Name)
 		}
 	}
+	if more {
+		fmt.Fprintf(os.Stderr, "There are more results\n")
+	}
 	return subcommands.ExitSuccess
 }
+
+// searchExtract prints the search extracts to stdout with highlighting for a terminal.
+func searchExtract(w io.Writer, items []*Page) {
+	heading := lipgloss.NewStyle().Bold(true).Underline(true)
+	quote := lipgloss.NewStyle().PaddingLeft(4).Width(78)
+	match := lipgloss.NewStyle().Bold(true)
+	re := regexp.MustCompile(`<b>(.*?)</b>`)
+	for _, p := range items {
+		s := re.ReplaceAllString(string(p.Html), match.Render(`$1`))
+		fmt.Fprintln(w, heading.Render(p.Title))
+		if p.Name != p.Title {
+			fmt.Fprintln(w, p.Name)
+		}
+		fmt.Fprintln(w, quote.Render(s))
+	}
+}

search_cmd_test.go

@@ -2,18 +2,17 @@ package main
 
 import (
 	"bytes"
+	"github.com/google/subcommands"
 	"github.com/stretchr/testify/assert"
 	"testing"
-	"github.com/google/subcommands"
 )
 
 func TestSearchCmd(t *testing.T) {
 	b := new(bytes.Buffer)
-	s := searchCli(b, 1, []string{"oddµ"})
+	s := searchCli(b, 1, false, false, true, []string{"oddµ"})
 	assert.Equal(t, subcommands.ExitSuccess, s)
-	r := `Search for oddµ, page 1: 2 results
-* [Oddµ: A minimal wiki](README) (5)
-* [Welcome to Oddµ](index) (5)
+	r := `* [Oddµ: A minimal wiki](README)
+* [Welcome to Oddµ](index)
 `
 	assert.Equal(t, r, b.String())
 }

search_test.go

@@ -1,30 +1,193 @@
 package main
 
 import (
+	"fmt"
 	"github.com/stretchr/testify/assert"
 	"net/url"
+	"slices"
 	"testing"
-	"os"
 )
 
+func TestSortNames(t *testing.T) {
+	index.Lock()
+	for _, s := range []string{"Alex", "Berta", "Chris", "2015-06-14", "2023-09-26"} {
+		index.titles[s] = s
+	}
+	index.Unlock()
+	terms := []string{"Z"}
+	fn := sortNames(terms)
+	assert.Equal(t, 1, fn("Berta", "Alex"), "B is after A")
+	assert.Equal(t, -1, fn("Alex", "Berta"), "A is before B")
+	assert.Equal(t, 0, fn("Berta", "Berta"), "B and B are equal")
+	assert.Equal(t, -1, fn("2023-09-26", "Alex"), "numbers before letters")
+	assert.Equal(t, 1, fn("Alex", "2023-09-26"), "numbers after letters")
+	assert.Equal(t, -1, fn("2023-09-26", "2015-06-14"), "higher numbers before lower numbers")
+	assert.Equal(t, 1, fn("2015-06-14", "2023-09-26"), "lower numbers after higher numbers")
+
+	names := []string{"Berta", "Chris", "Alex"}
+	slices.SortFunc(names, sortNames(terms))
+	assert.True(t, slices.IsSorted(names), fmt.Sprintf("Sorted: %v", names))
+}
+
+func TestPrependMatches(t *testing.T) {
+	index.Lock()
+	for _, s := range []string{"Alex", "Berta", "Chris"} {
+		index.titles[s] = s
+	}
+	index.Unlock()
+	r := []string{"Berta", "Chris"}         // does not prepend
+	u := []string{"Alex", "Berta", "Chris"} // does prepend
+	v, _ := prependQueryPage(r, "", "Alex")
+	assert.Equal(t, u, v, "prepend q")
+	v, _ = prependQueryPage(r, "", "lex")
+	assert.Equal(t, r, v, "exact matches only")
+	v, _ = prependQueryPage(r, "", "#Alex")
+	assert.Equal(t, u, v, "prepend hashtag")
+	v, _ = prependQueryPage(r, "", "#Alex #Berta")
+	assert.Equal(t, r, v, "do not prepend two hashtags")
+	v, _ = prependQueryPage(r, "", "#alex")
+	assert.Equal(t, r, v, "do not ignore case")
+	v, _ = prependQueryPage(u, "", "Alex")
+	assert.Equal(t, u, v, "do not prepend q twice")
+	v, _ = prependQueryPage([]string{"Berta", "Alex", "Chris"}, "", "Alex")
+	assert.Equal(t, u, v, "sort q to the front")
+	v, _ = prependQueryPage([]string{"Berta", "Chris", "Alex"}, "", "Alex")
+	assert.Equal(t, u, v, "sort q to the front")
+}
+
 func TestSearch(t *testing.T) {
 	data := url.Values{}
 	data.Set("q", "oddµ")
-	assert.Contains(t,
-		assert.HTTPBody(searchHandler, "GET", "/search", data), "Welcome")
+
+	body := assert.HTTPBody(makeHandler(searchHandler, false), "GET", "/search/", data)
+	assert.Contains(t, body, "Welcome")
+	assert.Contains(t, body, `<span class="score">5</span>`)
+
+	body = assert.HTTPBody(makeHandler(searchHandler, false), "GET", "/search/testdata", data)
+	assert.NotContains(t, body, "Welcome")
 }
 
-// wipes testdata
-func TestSearchQuestionmark(t *testing.T) {
-	_ = os.RemoveAll("testdata")
-	p := &Page{Name: "testdata/Odd?", Body: []byte(`# Even?
+func TestSearchDir(t *testing.T) {
+	cleanup(t, "testdata/dir")
+	p := &Page{Name: "testdata/dir/dice", Body: []byte(`# Dice
 
-yes or no?`)}
+A tiny drum roll
+Dice rolling bouncing stopping 
+Where is lady luck?`)}
+	p.save()
+
+	data := url.Values{}
+	data.Set("q", "luck")
+
+	body := assert.HTTPBody(makeHandler(searchHandler, false), "GET", "/search/", data)
+	assert.Contains(t, body, "luck")
+
+	body = assert.HTTPBody(makeHandler(searchHandler, false), "GET", "/search/testdata", data)
+	assert.Contains(t, body, "luck")
+
+	body = assert.HTTPBody(makeHandler(searchHandler, false), "GET", "/search/testdata/dir", data)
+	assert.Contains(t, body, "luck")
+
+	body = assert.HTTPBody(makeHandler(searchHandler, false), "GET", "/search/testdata/other", data)
+	assert.Contains(t, body, "No results")
+}
+
+func TestTitleSearch(t *testing.T) {
+	items, more := search("title:readme", "", 1, false)
+	assert.Equal(t, 0, len(items), "no page found")
+	assert.False(t, more)
+
+	items, more = search("title:wel", "", 1, false) // README also contains "wel"
+	assert.Equal(t, 1, len(items), "one page found")
+	assert.Equal(t, "index", items[0].Name, "Welcome to Oddµ")
+	assert.Greater(t, items[0].Score, 0, "matches result in a score")
+	assert.False(t, more)
+
+	items, more = search("wel", "", 1, false)
+	assert.Greater(t, len(items), 1, "two pages found")
+	assert.False(t, more)
+}
+
+func TestBlogSearch(t *testing.T) {
+	cleanup(t, "testdata/grep")
+	p := &Page{Name: "testdata/grep/2023-09-25", Body: []byte(`# Back then
+
+I check the git log
+Was it 2015
+We met in the park?`)}
+	p.save()
+
+	items, _ := search("blog:false", "", 1, false)
+	for _, item := range items {
+		assert.NotEqual(t, "Back then", item.Title, item.Name)
+	}
+
+	items, _ = search("blog:true", "", 1, false)
+	assert.Equal(t, 1, len(items), "one blog page found")
+	assert.Equal(t, "Back then", items[0].Title, items[0].Name)
+}
+
+func TestHashtagSearch(t *testing.T) {
+	cleanup(t, "testdata/hashtag")
+
+	p := &Page{Name: "testdata/hashtag/Haiku", Body: []byte("# Haikus\n")}
+	p.save()
+
+	p = &Page{Name: "testdata/hashtag/2023-10-28", Body: []byte(`# Tea
+
+My tongue is on fire
+It looked so calm and peaceful
+A quick sip too quick
+
+#Haiku`)}
+	p.save()
+
+	items, _ := search("#Haiku", "testdata/hashtag", 1, false)
+	assert.Equal(t, 2, len(items), "two pages found")
+	assert.Equal(t, "Haikus", items[0].Title, items[0].Name)
+	assert.Equal(t, "Tea", items[1].Title, items[1].Name)
+}
+
+func TestSearchQuestionmark(t *testing.T) {
+	cleanup(t, "testdata/question")
+	p := &Page{Name: "testdata/question/Odd?", Body: []byte(`# Even?
+
+We look at the plants.
+They need water. We need us.
+The silence streches.`)}
 	p.save()
 	data := url.Values{}
-	data.Set("q", "yes")
-	body := assert.HTTPBody(searchHandler, "GET", "/search", data)
-	assert.Contains(t, body, "yes or no?")
+	data.Set("q", "look")
+	body := assert.HTTPBody(makeHandler(searchHandler, false), "GET", "/search/", data)
+	assert.Contains(t, body, "We <b>look</b>")
 	assert.NotContains(t, body, "Odd?")
 	assert.Contains(t, body, "Even?")
 }
+
+func TestSearchPagination(t *testing.T) {
+	cleanup(t, "testdata/pagination")
+	index.load()
+	alphabet := "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+	for _, r := range alphabet {
+		s := fmt.Sprintf("secret%c secretX", r)
+		p := &Page{Name: "testdata/pagination/" + string(r), Body: []byte(s)}
+		p.save()
+	}
+
+	items, more := search("secretA", "", 1, false)
+	assert.Equal(t, 1, len(items), "one page found, %v", items)
+	assert.Equal(t, "testdata/pagination/A", items[0].Name)
+	assert.False(t, more)
+
+	items, more = search("secretX", "", 1, false)
+	assert.Equal(t, itemsPerPage, len(items))
+	assert.Equal(t, "testdata/pagination/A", items[0].Name)
+	assert.Equal(t, "testdata/pagination/T", items[itemsPerPage-1].Name)
+	assert.True(t, more)
+
+	items, more = search("secretX", "", 2, false)
+	assert.Equal(t, 6, len(items))
+	assert.Equal(t, "testdata/pagination/U", items[0].Name)
+	assert.Equal(t, "testdata/pagination/Z", items[5].Name)
+	assert.False(t, more)
+}

snippets.go

@@ -1,20 +1,21 @@
 package main
 
 import (
+	"log"
 	"regexp"
 	"strings"
 )
 
 // re returns a regular expression matching any word in q.
 func re(q string) (*regexp.Regexp, error) {
-	q = regexp.QuoteMeta(q)
-	re, err := regexp.Compile(`\s+`)
-	if err != nil {
-		return nil, err
+	fields := highlightTokens(q)
+	quoted := make([]string, len(fields))
+	for i, w := range fields {
+		quoted[i] = regexp.QuoteMeta(w)
 	}
-	words := re.ReplaceAllString(q, "|")
-	re, err = regexp.Compile(`(?i)(` + words + `)`)
+	re, err := regexp.Compile(`(?i)(` + strings.Join(quoted, "|") + `)`)
 	if err != nil {
+		log.Printf("Cannot compile %s %v: %s", q, quoted, err)
 		return nil, err
 	}
 	return re, nil
@@ -26,12 +27,16 @@ func snippets(q string, s string) string {
 	maxsnippets := 4
 	re, err := re(q)
 	// If the compilation didn't work, truncate and return
-	if err != nil || len(s) <= snippetlen {
+	if err != nil {
 		if len(s) > 400 {
 			s = s[0:400] + " …"
 		}
 		return s
 	}
+	// Short cut for short pages
+	if len(s) <= snippetlen {
+		return highlight(q, re, s)
+	}
 	// show a snippet from the beginning of the document
 	j := strings.LastIndex(s[:snippetlen], " ")
 	if j == -1 {

snippets_test.go

@@ -10,7 +10,7 @@ func TestSnippets(t *testing.T) {
 
 	h := `We are immersed in a sea of dead people. <b>All</b> the dead that have gone before us, silent now, just … to ask ourselves – or them! – what it was <b>all</b> about. Instead we drown ourselves in no<b>is</b>e. … surrounded by false friends claiming that <b>all</b> <b>is</b> <b>well</b>. And look at us! Yes, we are <b>well</b>. …`
 
-	q := "all is well"
+	q := "title:all is well"
 	r := snippets(q, s)
 	assert.Equal(t, h, r)
 }

static.html

@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<html lang="{{.Language}}">
+  <head>
+    <meta charset="utf-8">
+    <meta name="format-detection" content="telephone=no">
+    <meta name="viewport" content="width=device-width">
+    <title>{{.Title}}</title>
+    <style>
+html { max-width: 65ch; padding: 1ch; margin: auto; color: #111; background-color: #ffe; }
+body { hyphens: auto; }
+header a { margin-right: 1ch; }
+form { display: inline-block; }
+input#search { width: 12ch; }
+button { background-color: #eee; color: inherit; border-radius: 4px; border-width: 1px; }
+footer { border-top: 1px solid #888 }
+img { max-width: 100%; }
+    </style>
+  </head>
+  <body>
+    <main id="main">
+      <h1>{{.Title}}</h1>
+      {{.Html}}
+    </main>
+    <footer>
+      <address>
+        Comments? Send mail to Your Name <<a href="mailto:you@example.org">you@example.org</a>>
+      </address>
+    </footer>
+  </body>
+</html>

static_cmd.go

@@ -0,0 +1,147 @@
+package main
+
+import (
+	"bytes"
+	"context"
+	"flag"
+	"fmt"
+	"github.com/gomarkdown/markdown"
+	"github.com/gomarkdown/markdown/ast"
+	"github.com/gomarkdown/markdown/html"
+	"github.com/google/subcommands"
+	"io/fs"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+type staticCmd struct {
+}
+
+func (*staticCmd) Name() string     { return "static" }
+func (*staticCmd) Synopsis() string { return "generate static HTML files for all pages" }
+func (*staticCmd) Usage() string {
+	return `static <dir name>:
+  Create static copies in the given directory.
+`
+}
+
+func (cmd *staticCmd) SetFlags(f *flag.FlagSet) {
+}
+
+func (cmd *staticCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
+	args := f.Args()
+	if len(args) != 1 {
+		fmt.Println("Exactly one target directory is required")
+		return subcommands.ExitFailure
+	}
+	return staticCli(filepath.Clean(args[0]))
+}
+
+func staticCli(dir string) subcommands.ExitStatus {
+	err := os.Mkdir(dir, 0755)
+	if err != nil {
+		fmt.Println(err)
+		return subcommands.ExitFailure
+	}
+	initAccounts()
+	err = filepath.Walk(".", func(path string, info fs.FileInfo, err error) error {
+		return staticFile(path, dir, info, err)
+	})
+	if err != nil {
+		fmt.Println(err)
+		return subcommands.ExitFailure
+	}
+	return subcommands.ExitSuccess
+}
+
+// staticFile is used to walk the file trees and do the right thing for the destination directory: create
+// subdirectories, link files, render HTML files.
+func staticFile(path, dir string, info fs.FileInfo, err error) error {
+	if err != nil {
+		return err
+	}
+	filename := path
+	// skip "hidden" files and backup files, avoid recursion
+	if strings.HasPrefix(filename, ".") ||
+		strings.HasSuffix(filename, "~") ||
+		strings.HasPrefix(filename, dir) {
+		return nil
+	}
+	// recreate subdirectories
+	if info.IsDir() {
+		return os.Mkdir(filepath.Join(dir, filename), 0755)
+	}
+	// render pages
+	if strings.HasSuffix(filename, ".md") {
+		return staticPage(filename, dir)
+	}
+	// remaining files are linked
+	return os.Link(filename, filepath.Join(dir, filename))
+}
+
+// staticPage takes the filename of a page (ending in ".md") and generates a static HTML page.
+func staticPage(filename, dir string) error {
+	name := strings.TrimSuffix(filename, ".md")
+	p, err := loadPage(name)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Cannot load %s: %s\n", name, err)
+		return err
+	}
+	p.handleTitle(true)
+	// instead of p.renderHtml() we do it all ourselves, appending ".html" to all the local links
+	parser, hashtags := wikiParser()
+	doc := markdown.Parse(p.Body, parser)
+	ast.WalkFunc(doc, staticLinks)
+	opts := html.RendererOptions{
+		Flags: html.CommonFlags,
+	}
+	renderer := html.NewRenderer(opts)
+	maybeUnsafeHTML := markdown.Render(doc, renderer)
+	p.Name = nameEscape(p.Name)
+	p.Html = unsafeBytes(maybeUnsafeHTML)
+	p.Language = language(p.plainText())
+	p.Hashtags = *hashtags
+	return p.write(filepath.Join(dir, name+".html"))
+}
+
+// staticLinks checks a node and if it is a link to a local page, it appends ".html" to the link destination.
+func staticLinks(node ast.Node, entering bool) ast.WalkStatus {
+	if entering {
+		switch v := node.(type) {
+		case *ast.Link:
+			// not an absolute URL, not a full URL, not a mailto: URI
+			if !bytes.HasPrefix(v.Destination, []byte("/")) &&
+				!bytes.Contains(v.Destination, []byte("://")) &&
+				!bytes.HasPrefix(v.Destination, []byte("mailto:")) {
+				// pointing to a page file (instead of an image file, for example).
+				fn, err := url.PathUnescape(string(v.Destination))
+				if err != nil {
+					return ast.GoToNext
+				}
+				_, err = os.Stat(fn + ".md")
+				if err != nil {
+					return ast.GoToNext
+				}
+				v.Destination = append(v.Destination, []byte(".html")...)
+			}
+		}
+	}
+	return ast.GoToNext
+}
+
+func (p *Page) write(destination string) error {
+	t := "static.html"
+	f, err := os.Create(destination)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Cannot create %s.html: %s\n", destination, err)
+		return err
+	}
+	err = templates.ExecuteTemplate(f, t, p)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Cannot execute %s template for %s: %s\n", t, destination, err)
+		return err
+	}
+	return nil
+}

static_cmd_test.go

@@ -0,0 +1,19 @@
+package main
+
+import (
+	"github.com/google/subcommands"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestStatusCmd(t *testing.T) {
+	cleanup(t, "testdata/static")
+	s := staticCli("testdata/static")
+	assert.Equal(t, subcommands.ExitSuccess, s)
+	// pages
+	assert.FileExists(t, "testdata/static/index.html")
+	assert.FileExists(t, "testdata/static/README.html")
+	// regular files
+	assert.FileExists(t, "testdata/static/static_cmd.go")
+	assert.FileExists(t, "testdata/static/static_cmd_test.go")
+}

tokenizer.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"bytes"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// lowercaseFilter returns a slice of lower case tokens.
+func lowercaseFilter(tokens []string) []string {
+	r := make([]string, len(tokens))
+	for i, token := range tokens {
+		r[i] = strings.ToLower(token)
+	}
+	return r
+}
+
+// tokenizeWithPredicates returns a slice of tokens for the given
+// text, including punctuation. Use this to begin tokenizing the query
+// string.
+func tokenizeOnWhitespace(q string) []string {
+	return strings.Fields(q)
+}
+
+// predicateFilter returns two slices of tokens: the first with
+// predicates, the other without predicates. Use this for query
+// string tokens.
+func predicateFilter(tokens []string) ([]string, []string) {
+	with := make([]string, 0)
+	without := make([]string, 0)
+	for _, token := range tokens {
+		if strings.Contains(token, ":") {
+			with = append(with, token)
+		} else {
+			without = append(without, token)
+		}
+	}
+	return with, without
+}
+
+// predicatesAndTokens returns two slices of tokens: the first with
+// predicates, the other without predicates, all of them lower case.
+// Use this for query strings.
+func predicatesAndTokens(q string) ([]string, []string) {
+	tokens := tokenizeOnWhitespace(q)
+	tokens = lowercaseFilter(tokens)
+	return predicateFilter(tokens)
+}
+
+// noPredicateFilter returns a slice of tokens: the predicates without
+// the predicate, and all the others. That is: "foo:bar baz" is turned
+// into ["bar", "baz"] and the predicate "foo:" is dropped.
+func noPredicateFilter(tokens []string) []string {
+	r := make([]string, 0)
+	for _, token := range tokens {
+		parts := strings.Split(token, ":")
+		r = append(r, parts[len(parts)-1])
+	}
+	return r
+}
+
+// highlightTokens returns the tokens to highlight, including title
+// predicates.
+func highlightTokens(q string) []string {
+	tokens := tokenizeOnWhitespace(q)
+	tokens = lowercaseFilter(tokens)
+	return noPredicateFilter(tokens)
+}
+
+// hashtags returns a slice of hashtags. Use this to extract hashtags
+// from a page body.
+func hashtags(s []byte) []string {
+	hashtags := make([]string, 0)
+	for {
+		i := bytes.IndexRune(s, '#')
+		if i == -1 {
+			return hashtags
+		}
+		from := i
+		i++
+		for {
+			r, n := utf8.DecodeRune(s[i:])
+			if n > 0 && (unicode.IsLetter(r) || unicode.IsNumber(r) || r == '_') {
+				i += n
+			} else {
+				break
+			}
+		}
+		if i > from+1 { // not just "#"
+			hashtags = append(hashtags, string(bytes.ToLower(s[from:i])))
+		}
+		s = s[i:]
+	}
+}

tokenizer_test.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestHashtags(t *testing.T) {
+	assert.EqualValues(t, []string{"#truth"}, hashtags([]byte("This is boring. #Truth")), "hashtags")
+}
+
+func TestTokensAndPredicates(t *testing.T) {
+	predicates, terms := predicatesAndTokens("foo title:bar")
+	assert.EqualValues(t, []string{"foo"}, terms)
+	assert.EqualValues(t, []string{"title:bar"}, predicates)
+}

upload.html

@@ -6,28 +6,35 @@
     <meta name="viewport" content="width=device-width">
     <title>Upload File</title>
     <style>
-html { max-width: 70ch; padding: 2ch; margin: auto; color: #111; background: #ffe; }
+html { max-width: 70ch; padding: 2ch; margin: auto; color: #111; background-color: #ffe; }
 body { hyphens: auto; }
 form, textarea { width: 100%; }
 label { display: inline-block; width: 20ch }
+.last { max-width: 20% }
     </style>
   </head>
   <body lang="en">
     <h1>Upload File</h1>
-    <form action="/drop/{{.}}" method="POST" enctype="multipart/form-data">
+    {{if ne .Last ""}}
+    <p>Previous upload: <a href="/view/{{.Last}}">{{.Last}}</a></p>
+    {{if .Image}}
+    <p><img class="last" src="/view/{{.Last}}"></p>
+    {{end}}
+    {{end}}
+    <form action="/drop/{{.Dir}}" method="POST" enctype="multipart/form-data">
       <p>When uploading pictures from a phone, its filename is going to be something cryptic like IMG_1234.JPG.
         Please provide your own filename.
       <p><label for="text">Filename to use:</label>
-        <input id="text" name="name" type="text" placeholder="image.jpg" autofocus required>
+        <input id="text" name="name" value="{{.Name}}" type="text" placeholder="image.jpg" autofocus required>
       <p>If the uploaded file is a picture from a phone, it is going to be too big for your site.
         Sadly, resizing only works for JPG and PNG files. Luckily, most pictures from a phone camera are JPG images.
         Feel free to specify a max width of 1200 pixels, for example.
       <p><label for="maxwidth">Max width:</label>
-        <input id="maxwidth" name="maxwidth" type="number" min="10" placeholder="1200">
+        <input id="maxwidth" name="maxwidth" value="{{.MaxWidth}}" type="number" min="10" placeholder="1200">
       <p>If the uploaded file is a JPEG-encoded picture, like most pictures from a phone, you can specify a quality.
         Typically, a quality of 60 is not too bad and a quality of 90 is more than enough.
       <p><label for="quality">Quality:</label>
-        <input id="quality" name="quality" type="number" min="1" max="99" placeholder="75">
+        <input id="quality" name="quality" value="{{.Quality}}" type="number" min="1" max="99" placeholder="75">
       <p>Finally, pick the file or photo to upload.
         Picture metadata is only removed if the picture gets resized.
         Providing a new max width is recommended for all pictures.

upload_drop.go

@@ -6,17 +6,58 @@ import (
 	"image/jpeg"
 	"io"
 	"net/http"
+	"net/url"
 	"os"
 	"path"
 	"path/filepath"
+	"regexp"
 	"strconv"
 	"strings"
 )
 
+type Upload struct {
+	Dir      string
+	Name     string
+	Last     string
+	Image    bool
+	MaxWidth string
+	Quality  string
+}
+
+var lastRe = regexp.MustCompile(`^(.*)([0-9]+)(.*)$`)
+
 // uploadHandler uses the "upload.html" template to enable uploads.
-// The file is saved using the saveUploadHandler.
+// The file is saved using the saveUploadHandler. URL parameter are
+// used to copy name, maxwidth and quality from the previous upload.
+// If the previous name contains a number, this is incremented by
+// one.
 func uploadHandler(w http.ResponseWriter, r *http.Request, dir string) {
-	renderTemplate(w, "upload", dir)
+	data := &Upload{Dir: dir}
+	maxwidth := r.FormValue("maxwidth")
+	if maxwidth != "" {
+		data.MaxWidth = maxwidth
+	}
+	quality := r.FormValue("quality")
+	if quality != "" {
+		data.Quality = quality
+	}
+	last := r.FormValue("last")
+	if last != "" {
+		ext := strings.ToLower(filepath.Ext(last))
+		switch ext {
+		case ".png", ".jpg", ".jpeg":
+			data.Image = true
+		}
+		data.Last = path.Join(dir, last)
+		m := lastRe.FindStringSubmatch(last)
+		if m != nil {
+			n, err := strconv.Atoi(m[2])
+			if err == nil {
+				data.Name = m[1] + strconv.Itoa(n+1) + m[3]
+			}
+		}
+	}
+	renderTemplate(w, "upload", data)
 }
 
 // dropHandler takes the "name" form field and the "file" form
@@ -34,7 +75,9 @@ func dropHandler(w http.ResponseWriter, r *http.Request, dir string) {
 		http.Error(w, "file exists", http.StatusInternalServerError)
 		return
 	}
+	data := url.Values{}
 	name := r.FormValue("name")
+	data.Set("last", name)
 	filename := filepath.Base(name)
 	if filename == "." || filepath.Dir(name) != "." {
 		http.Error(w, "no filename", http.StatusInternalServerError)
@@ -46,11 +89,7 @@ func dropHandler(w http.ResponseWriter, r *http.Request, dir string) {
 		return
 	}
 	defer file.Close()
-	// backup an existing file with the same name
-	_, err = os.Stat(filename)
-	if err != nil {
-		os.Rename(filename, filename+"~")
-	}
+	backup(filename)
 	// create the new file
 	path := d + "/" + filename
 	dst, err := os.Create(path)
@@ -71,6 +110,7 @@ func dropHandler(w http.ResponseWriter, r *http.Request, dir string) {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
+		data.Add("maxwidth", maxwidth)
 		ext := strings.ToLower(filepath.Ext(path))
 		var encoder imgio.Encoder
 		switch ext {
@@ -85,6 +125,7 @@ func dropHandler(w http.ResponseWriter, r *http.Request, dir string) {
 					http.Error(w, err.Error(), http.StatusInternalServerError)
 					return
 				}
+				data.Add("quality", quality)
 			}
 			encoder = imgio.JPEGEncoder(q)
 		default:
@@ -108,5 +149,5 @@ func dropHandler(w http.ResponseWriter, r *http.Request, dir string) {
 		}
 
 	}
-	http.Redirect(w, r, "/view/"+path, http.StatusFound)
+	http.Redirect(w, r, "/upload/"+d+"/?"+data.Encode(), http.StatusFound)
 }

upload_drop_test.go

@@ -7,17 +7,16 @@ import (
 	"image/jpeg"
 	"image/png"
 	"mime/multipart"
+	"net/url"
 	"os"
-	"regexp"
 	"testing"
 )
 
-// wipes testdata
 func TestUpload(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/files")
 	// for uploads, the directory is not created automatically
-	os.MkdirAll("testdata", 0755)
-	assert.HTTPStatusCode(t, makeHandler(uploadHandler, false), "GET", "/upload/testdata/", nil, 200)
+	os.MkdirAll("testdata/files", 0755)
+	assert.HTTPStatusCode(t, makeHandler(uploadHandler, false), "GET", "/upload/testdata/files/", nil, 200)
 	form := new(bytes.Buffer)
 	writer := multipart.NewWriter(form)
 	field, err := writer.CreateFormField("name")
@@ -29,20 +28,17 @@ func TestUpload(t *testing.T) {
 	file.Write([]byte("Hello!"))
 	err = writer.Close()
 	assert.NoError(t, err)
-	HTTPUploadAndRedirectTo(t, makeHandler(dropHandler, false), "/drop/testdata/",
-		writer.FormDataContentType(), form, "/view/testdata/ok.txt")
-	assert.Regexp(t, regexp.MustCompile("Hello!"),
-		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/ok.txt", nil))
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+	HTTPUploadAndRedirectTo(t, makeHandler(dropHandler, false), "/drop/testdata/files/",
+		writer.FormDataContentType(), form, "/upload/testdata/files/?last=ok.txt")
+	assert.Contains(t,
+		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/files/ok.txt", nil),
+		"Hello!")
 }
 
-// wipes testdata
 func TestUploadPng(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/png")
 	// for uploads, the directory is not created automatically
-	os.MkdirAll("testdata", 0755)
+	os.MkdirAll("testdata/png", 0755)
 	form := new(bytes.Buffer)
 	writer := multipart.NewWriter(form)
 	field, _ := writer.CreateFormField("name")
@@ -51,18 +47,14 @@ func TestUploadPng(t *testing.T) {
 	img := image.NewRGBA(image.Rect(0, 0, 20, 20))
 	png.Encode(file, img)
 	writer.Close()
-	HTTPUploadAndRedirectTo(t, makeHandler(dropHandler, false), "/drop/testdata/",
-		writer.FormDataContentType(), form, "/view/testdata/ok.png")
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+	HTTPUploadAndRedirectTo(t, makeHandler(dropHandler, false), "/drop/testdata/png/",
+		writer.FormDataContentType(), form, "/upload/testdata/png/?last=ok.png")
 }
 
-// wipes testdata
 func TestUploadJpg(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/jpg")
 	// for uploads, the directory is not created automatically
-	os.MkdirAll("testdata", 0755)
+	os.MkdirAll("testdata/jpg", 0755)
 	form := new(bytes.Buffer)
 	writer := multipart.NewWriter(form)
 	field, _ := writer.CreateFormField("name")
@@ -71,9 +63,94 @@ func TestUploadJpg(t *testing.T) {
 	img := image.NewRGBA(image.Rect(0, 0, 20, 20))
 	jpeg.Encode(file, img, &jpeg.Options{Quality: 90})
 	writer.Close()
-	HTTPUploadAndRedirectTo(t, makeHandler(dropHandler, false), "/drop/testdata/",
-		writer.FormDataContentType(), form, "/view/testdata/ok.jpg")
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+	HTTPUploadAndRedirectTo(t, makeHandler(dropHandler, false), "/drop/testdata/jpg/",
+		writer.FormDataContentType(), form, "/upload/testdata/jpg/?last=ok.jpg")
+}
+
+func TestUploadMultiple(t *testing.T) {
+	cleanup(t, "testdata/multi")
+	p := &Page{Name: "testdata/multi/culture", Body: []byte(`# Culture
+
+The road has walls
+Iron gates and tree tops
+But here: jasmin dreams`)}
+	p.save()
+
+	// check location for upload
+	body := assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/multi/culture", nil)
+	assert.Contains(t, body, `href="/upload/testdata/multi/"`)
+
+	// check location for drop
+	body = assert.HTTPBody(makeHandler(uploadHandler, false), "GET", "/upload/testdata/multi/", nil)
+	assert.Contains(t, body, `action="/drop/testdata/multi/"`)
+
+	// actually do the upload
+	form := new(bytes.Buffer)
+	writer := multipart.NewWriter(form)
+	field, _ := writer.CreateFormField("name")
+	field.Write([]byte("2023-10-02-hike-1.jpg"))
+	field, _ = writer.CreateFormField("maxwidth")
+	field.Write([]byte("15"))
+	field, _ = writer.CreateFormField("quality")
+	field.Write([]byte("50"))
+	file, _ := writer.CreateFormFile("file", "ok.jpg")
+	img := image.NewRGBA(image.Rect(0, 0, 20, 20))
+	jpeg.Encode(file, img, &jpeg.Options{Quality: 90})
+	writer.Close()
+	location := HTTPUploadLocation(t, makeHandler(dropHandler, false), "/drop/testdata/multi/",
+		writer.FormDataContentType(), form)
+	url, _ := url.Parse(location)
+	assert.Equal(t, "/upload/testdata/multi/", url.Path, "Redirect to upload location")
+	values := url.Query()
+	assert.Equal(t, "2023-10-02-hike-1.jpg", values.Get("last"))
+	assert.Equal(t, "15", values.Get("maxwidth"))
+	assert.Equal(t, "50", values.Get("quality"))
+
+	// check the result page
+	body = assert.HTTPBody(makeHandler(uploadHandler, false), "GET", url.Path, values)
+	assert.Contains(t, body, `value="2023-10-02-hike-2.jpg"`)
+	assert.Contains(t, body, `value="15"`)
+	assert.Contains(t, body, `value="50"`)
+	assert.Contains(t, body, `src="/view/testdata/multi/2023-10-02-hike-1.jpg"`)
+}
+
+func TestUploadDir(t *testing.T) {
+	t.Cleanup(func() {
+		assert.NoError(t, os.Remove("test.md"))
+		assert.NoError(t, os.Remove("test.jpg"))
+	})
+	p := &Page{Name: "test", Body: []byte(`# Test
+
+Eyes are an abyss
+We stare into each other
+There is no answer`)}
+	p.save()
+
+	// check location for upload
+	body := assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/test", nil)
+	assert.Contains(t, body, `href="/upload/"`)
+
+	// check location for drop
+	body = assert.HTTPBody(makeHandler(uploadHandler, false), "GET", "/upload/", nil)
+	assert.Contains(t, body, `action="/drop/"`)
+
+	// actually do the upload
+	form := new(bytes.Buffer)
+	writer := multipart.NewWriter(form)
+	field, _ := writer.CreateFormField("name")
+	field.Write([]byte("test.jpg"))
+	file, _ := writer.CreateFormFile("file", "ok.jpg")
+	img := image.NewRGBA(image.Rect(0, 0, 20, 20))
+	jpeg.Encode(file, img, &jpeg.Options{Quality: 90})
+	writer.Close()
+	location := HTTPUploadLocation(t, makeHandler(dropHandler, false), "/drop/",
+		writer.FormDataContentType(), form)
+	url, _ := url.Parse(location)
+	assert.Equal(t, "/upload/", url.Path, "Redirect to upload location")
+	values := url.Query()
+	assert.Equal(t, "test.jpg", values.Get("last"))
+
+	// check the result page
+	body = assert.HTTPBody(makeHandler(uploadHandler, false), "GET", url.Path, values)
+	assert.Contains(t, body, `src="/view/test.jpg"`)
 }

view.go

@@ -3,8 +3,9 @@ package main
 import (
 	"net/http"
 	"os"
-	"time"
+	"path"
 	"strings"
+	"time"
 )
 
 // rootHandler just redirects to /view/index.
@@ -12,30 +13,36 @@ func rootHandler(w http.ResponseWriter, r *http.Request) {
 	http.Redirect(w, r, "/view/index", http.StatusFound)
 }
 
-// viewHandler serves existing files (including markdown files with
-// the .md extension). If the requested file does not exist, a page
-// with the same name is loaded. This means adding the .md extension
-// and using the "view.html" template to render the HTML. Both
-// attempts fail, the browser is redirected to an edit page. As far as
-// caching goes: we respond with a 304 NOT MODIFIED if the request has
-// an If-Modified-Since header that matches the file's modification
-// time, truncated to one second, because the file's modtime has
-// sub-second precision and the HTTP timestamp for the Last-Modified
-// header has not.
+// viewHandler serves pages. If the requested URL maps to an existing file, it is served. If the requested URL maps to a
+// directory, the browser is redirected to the index page. If the requested URL ends in ".rss" and the corresponding
+// file ending with ".md" exists, a feed is generated and the "feed.html" template is used (it is used to generate a RSS
+// 2.0 feed, no matter what the template's extension is). If the requested URL maps to a page name, the corresponding
+// file (ending in ".md") is loaded and served using the "view.html" template. If none of the above, the browser is
+// redirected to an edit page.
+//
+// Caching: a 304 NOT MODIFIED is returned if the request has an If-Modified-Since header that matches the file's
+// modification time, truncated to one second. Truncation is required because the file's modtime has sub-second
+// precision and the HTTP timestamp for the Last-Modified header has not.
 func viewHandler(w http.ResponseWriter, r *http.Request, name string) {
 	file := true
 	rss := false
+	if name == "" {
+		name = "."
+	}
 	fn := name
 	fi, err := os.Stat(fn)
 	if err != nil {
 		file = false
 		if strings.HasSuffix(fn, ".rss") {
 			rss = true
-			name = fn[0:len(fn)-4]
+			name = fn[0 : len(fn)-4]
 			fn = name
 		}
 		fn += ".md"
 		fi, err = os.Stat(fn)
+	} else if fi.IsDir() {
+		http.Redirect(w, r, path.Join("/view", name, "index"), http.StatusFound)
+		return
 	}
 	if err == nil {
 		h, ok := r.Header["If-Modified-Since"]

view.html

@@ -6,12 +6,12 @@
     <meta name="viewport" content="width=device-width">
     <title>{{.Title}}</title>
     <style>
-html { max-width: 65ch; padding: 1ch; margin: auto; color: #111; background: #ffe; }
+html { max-width: 65ch; padding: 1ch; margin: auto; color: #111; background-color: #ffe; }
 body { hyphens: auto; }
 header a { margin-right: 1ch; }
 form { display: inline-block; }
 input#search { width: 12ch; }
-button { background: #eee; color: inherit; border-radius: 4px; border-width: 1px; }
+button { background-color: #eee; color: inherit; border-radius: 4px; border-width: 1px; }
 footer { border-top: 1px solid #888 }
 img { max-width: 100%; }
     </style>
@@ -22,10 +22,11 @@ img { max-width: 100%; }
       <a href="/view/index">Home</a>
       <a href="/edit/{{.Name}}" accesskey="e">Edit</a>
       <a href="/add/{{.Name}}" accesskey="a">Add</a>
+      <a href="/diff/{{.Name}}" accesskey="d">Diff</a>
       <a href="/upload/{{.Dir}}" accesskey="u">Upload</a>
-      <form role="search" action="/search" method="GET">
+      <form role="search" action="/search/{{.Dir}}" method="GET">
         <label for="search">Search:</label>
-        <input id="search" type="text" spellcheck="false" name="q" accesskey="f" required>
+        <input id="search" type="text" spellcheck="false" name="q" accesskey="f" placeholder="term #tag title:term blog:true" required>
         <button>Go</button>
       </form>
     </header>

view_test.go

@@ -3,6 +3,7 @@ package main
 import (
 	"github.com/stretchr/testify/assert"
 	"net/http"
+	"net/url"
 	"os"
 	"regexp"
 	"testing"
@@ -18,105 +19,97 @@ func TestViewHandler(t *testing.T) {
 		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/index", nil))
 }
 
-// wipes testdata
-func TestPageTitleWithAmp(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+func TestViewHandlerDir(t *testing.T) {
+	HTTPRedirectTo(t, makeHandler(viewHandler, true), "GET", "/view/", nil, "/view/index")
+	HTTPRedirectTo(t, makeHandler(viewHandler, true), "GET", "/view/man", nil, "/view/man/index")
+	HTTPRedirectTo(t, makeHandler(viewHandler, true), "GET", "/view/man/", nil, "/view/man/index")
+}
 
-	p := &Page{Name: "testdata/Rock & Roll", Body: []byte("Dancing")}
+// relies on index.md in the current directory!
+func TestViewHandlerWithId(t *testing.T) {
+	data := make(url.Values)
+	data.Set("id", "index")
+	assert.Regexp(t, regexp.MustCompile("Welcome to Oddµ"),
+		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/", data))
+}
+
+func TestPageTitleWithAmp(t *testing.T) {
+	cleanup(t, "testdata/amp")
+
+	p := &Page{Name: "testdata/amp/Rock & Roll", Body: []byte("Dancing")}
 	p.save()
 
 	assert.Regexp(t, regexp.MustCompile("Rock & Roll"),
-		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/Rock%20%26%20Roll", nil))
+		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/amp/Rock%20%26%20Roll", nil))
 
-	p = &Page{Name: "testdata/Rock & Roll", Body: []byte("# Sex & Drugs & Rock'n'Roll\nOh no!")}
+	p = &Page{Name: "testdata/amp/Rock & Roll", Body: []byte("# Sex & Drugs & Rock'n'Roll\nOh no!")}
 	p.save()
 
 	assert.Regexp(t, regexp.MustCompile("Sex & Drugs"),
-		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/Rock%20%26%20Roll", nil))
-
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+		assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/amp/Rock%20%26%20Roll", nil))
 }
 
-// wipes testdata
 func TestPageTitleWithQuestionMark(t *testing.T) {
-	_ = os.RemoveAll("testdata")
+	cleanup(t, "testdata/q")
 
-	p := &Page{Name: "testdata/How about no?", Body: []byte("No means no")}
+	p := &Page{Name: "testdata/q/How about no?", Body: []byte("No means no")}
 	p.save()
 
-	body := assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/How%20about%20no%3F", nil)
+	body := assert.HTTPBody(makeHandler(viewHandler, true), "GET", "/view/testdata/q/How%20about%20no%3F", nil)
 	assert.Contains(t, body, "No means no")
-	assert.Contains(t, body, "<a href=\"/edit/testdata/How%20about%20no%3F\" accesskey=\"e\">Edit</a>")
-
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+	assert.Contains(t, body, "<a href=\"/edit/testdata/q/How%20about%20no%3F\" accesskey=\"e\">Edit</a>")
 }
 
-// wipes testdata
 func TestFileLastModified(t *testing.T) {
-	_ = os.RemoveAll("testdata")
-	assert.NoError(t, os.Mkdir("testdata", 0755))
-	assert.NoError(t, os.WriteFile("testdata/now.txt", []byte(`
+	cleanup(t, "testdata/file-mod")
+	assert.NoError(t, os.Mkdir("testdata/file-mod", 0755))
+	assert.NoError(t, os.WriteFile("testdata/file-mod/now.txt", []byte(`
 A spider sitting
 Unmoving and still
 In the autumn chill
 `), 0644))
-	fi, err := os.Stat("testdata/now.txt")
+	fi, err := os.Stat("testdata/file-mod/now.txt")
 	assert.NoError(t, err)
 	h := makeHandler(viewHandler, true)
 	assert.Equal(t, []string{fi.ModTime().UTC().Format(http.TimeFormat)},
-		HTTPHeaders(h, "GET", "/view/testdata/now.txt", nil, "Last-Modified"))
-	HTTPStatusCodeIfModifiedSince(t, h, "/view/testdata/now.txt", fi.ModTime())
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+		HTTPHeaders(h, "GET", "/view/testdata/file-mod/now.txt", nil, "Last-Modified"))
+	HTTPStatusCodeIfModifiedSince(t, h, "/view/testdata/file-mod/now.txt", fi.ModTime())
 }
 
 // wipes testdata
 func TestPageLastModified(t *testing.T) {
-	_ = os.RemoveAll("testdata")
-	p := &Page{Name: "testdata/now", Body: []byte(`
+	cleanup(t, "testdata/page-mod")
+	p := &Page{Name: "testdata/page-mod/now", Body: []byte(`
 The sky glows softly
 Sadly, the birds are quiet
 I like spring better
 `)}
 	p.save()
-	fi, err := os.Stat("testdata/now.md")
+	fi, err := os.Stat("testdata/page-mod/now.md")
 	assert.NoError(t, err)
 	h := makeHandler(viewHandler, true)
 	assert.Equal(t, []string{fi.ModTime().UTC().Format(http.TimeFormat)},
-	HTTPHeaders(h, "GET", "/view/testdata/now", nil, "Last-Modified"))
-	HTTPStatusCodeIfModifiedSince(t, h, "/view/testdata/now", fi.ModTime())
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+		HTTPHeaders(h, "GET", "/view/testdata/page-mod/now", nil, "Last-Modified"))
+	HTTPStatusCodeIfModifiedSince(t, h, "/view/testdata/page-mod/now", fi.ModTime())
 }
 
-
-// wipes testdata
 func TestPageHead(t *testing.T) {
-	_ = os.RemoveAll("testdata")
-	p := &Page{Name: "testdata/peace", Body: []byte(`
+	cleanup(t, "testdata/head")
+	p := &Page{Name: "testdata/head/peace", Body: []byte(`
 No urgent typing
 No todos, no list, no queue.
 Just me and the birds.
 `)}
 	p.save()
-	fi, err := os.Stat("testdata/peace.md")
+	fi, err := os.Stat("testdata/head/peace.md")
 	assert.NoError(t, err)
 	h := makeHandler(viewHandler, true)
 	assert.Equal(t, []string(nil),
-		HTTPHeaders(h, "HEAD", "/view/testdata/war", nil, "Last-Modified"))
+		HTTPHeaders(h, "HEAD", "/view/testdata/head/war", nil, "Last-Modified"))
 	assert.Equal(t, []string(nil),
-		HTTPHeaders(h, "GET", "/view/testdata/war", nil, "Last-Modified"))
+		HTTPHeaders(h, "GET", "/view/testdata/head/war", nil, "Last-Modified"))
 	assert.Equal(t, []string{fi.ModTime().UTC().Format(http.TimeFormat)},
-		HTTPHeaders(h, "HEAD", "/view/testdata/peace", nil, "Last-Modified"))
+		HTTPHeaders(h, "HEAD", "/view/testdata/head/peace", nil, "Last-Modified"))
 	assert.Equal(t, "",
-		assert.HTTPBody(h, "HEAD", "/view/testdata/peace", nil))
-	t.Cleanup(func() {
-		_ = os.RemoveAll("testdata")
-	})
+		assert.HTTPBody(h, "HEAD", "/view/testdata/head/peace", nil))
 }

wiki.go

@@ -3,9 +3,9 @@ package main
 import (
 	"context"
 	"flag"
-	"fmt"
 	"github.com/google/subcommands"
 	"html/template"
+	"log"
 	"net/http"
 	"os"
 	"regexp"
@@ -13,8 +13,8 @@ import (
 
 // Templates are parsed at startup.
 var templates = template.Must(
-	template.ParseFiles("edit.html", "add.html", "view.html",
-		"search.html", "upload.html", "feed.html"))
+	template.ParseFiles("edit.html", "add.html", "view.html", "diff.html",
+		"search.html", "static.html", "upload.html", "feed.html"))
 
 // validPath is a regular expression where the second group matches a
 // page, so when the editHandler is called, a URL path of "/edit/foo"
@@ -38,20 +38,28 @@ func renderTemplate(w http.ResponseWriter, tmpl string, data any) {
 	}
 }
 
-// makeHandler returns a handler that uses the URL path without the
-// first path element as its argument, e.g. if the URL path is
-// /edit/foo/bar, the editHandler is called with "foo/bar" as its
-// argument. This uses the second group from the validPath regular
-// expression. The boolean argument indicates whether the following
-// path is required. When false, a URL /upload/ is OK.
+// makeHandler returns a handler that uses the URL path without the first path element as its argument, e.g. if the URL
+// path is /edit/foo/bar, the editHandler is called with "foo/bar" as its argument. This uses the second group from the
+// validPath regular expression. The boolean argument indicates whether the following path is required. When false, a
+// URL like /upload/ is OK. The argument can also be provided using a form parameter, i.e. call /edit/?id=foo/bar.
 func makeHandler(fn func(http.ResponseWriter, *http.Request, string), required bool) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		m := validPath.FindStringSubmatch(r.URL.Path)
 		if m != nil && (!required || len(m[2]) > 0) {
 			fn(w, r, m[2])
-		} else {
-			http.NotFound(w, r)
+			return
 		}
+		err := r.ParseForm()
+		if err != nil {
+			http.Error(w, "Cannot parse form", 400)
+			return
+		}
+		id := r.Form.Get("id")
+		if m != nil {
+			fn(w, r, id)
+			return
+		}
+		http.NotFound(w, r)
 	}
 }
 
@@ -69,12 +77,12 @@ func getPort() string {
 // and after. For testing, call index.load directly and skip the
 // messages.
 func scheduleLoadIndex() {
-	fmt.Print("Indexing pages\n")
+	log.Print("Indexing pages")
 	n, err := index.load()
 	if err == nil {
-		fmt.Printf("Indexed %d pages\n", n)
+		log.Printf("Indexed %d pages", n)
 	} else {
-		fmt.Println("Indexing failed")
+		log.Printf("Indexing failed: %s", err)
 	}
 }
 
@@ -82,27 +90,31 @@ func scheduleLoadIndex() {
 // and after. For testing, call loadLanguages directly and skip the
 // messages.
 func scheduleLoadLanguages() {
-	fmt.Print("Loading languages\n")
+	log.Print("Loading languages")
 	n := loadLanguages()
-	fmt.Printf("Loaded %d languages\n", n)
+	log.Printf("Loaded %d languages", n)
 }
 
 func serve() {
 	http.HandleFunc("/", rootHandler)
 	http.HandleFunc("/view/", makeHandler(viewHandler, true))
+	http.HandleFunc("/diff/", makeHandler(diffHandler, true))
 	http.HandleFunc("/edit/", makeHandler(editHandler, true))
 	http.HandleFunc("/save/", makeHandler(saveHandler, true))
 	http.HandleFunc("/add/", makeHandler(addHandler, true))
 	http.HandleFunc("/append/", makeHandler(appendHandler, true))
 	http.HandleFunc("/upload/", makeHandler(uploadHandler, false))
 	http.HandleFunc("/drop/", makeHandler(dropHandler, false))
-	http.HandleFunc("/search", searchHandler)
+	http.HandleFunc("/search/", makeHandler(searchHandler, false))
 	go scheduleLoadIndex()
 	go scheduleLoadLanguages()
 	initAccounts()
 	port := getPort()
-	fmt.Printf("Serving a wiki on port %s\n", port)
-	http.ListenAndServe(":"+port, nil)
+	log.Printf("Serving a wiki on port %s", port)
+	err := http.ListenAndServe(":"+port, nil)
+	if err != nil {
+		log.Println(err)
+	}
 }
 
 // commands does the command line parsing in case Oddmu is called with
@@ -114,8 +126,11 @@ func commands() {
 	subcommands.Register(subcommands.FlagsCommand(), "")
 	subcommands.Register(subcommands.CommandsCommand(), "")
 	subcommands.Register(&htmlCmd{}, "")
+	subcommands.Register(&staticCmd{}, "")
 	subcommands.Register(&searchCmd{}, "")
 	subcommands.Register(&replaceCmd{}, "")
+	subcommands.Register(&missingCmd{}, "")
+	subcommands.Register(&notifyCmd{}, "")
 
 	flag.Parse()
 	ctx := context.Background()

wiki_test.go

@@ -6,6 +6,8 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"os"
+	"slices"
 	"strings"
 	"testing"
 	"time"
@@ -49,10 +51,8 @@ func HTTPRedirectTo(t *testing.T, handler http.HandlerFunc, method, url string,
 	return isRedirectCode
 }
 
-// HTTPUploadAndRedirectTo checks that the request results in a redirect and it
-// checks the destination of the redirect. It returns whether the
-// request did in fact result in a redirect.
-func HTTPUploadAndRedirectTo(t *testing.T, handler http.HandlerFunc, url, contentType string, body *bytes.Buffer, destination string) bool {
+// HTTPUploadLocation returns the location header after an upload.
+func HTTPUploadLocation(t *testing.T, handler http.HandlerFunc, url, contentType string, body *bytes.Buffer) string {
 	w := httptest.NewRecorder()
 	req, err := http.NewRequest("POST", url, body)
 	req.Header.Set("Content-Type", contentType)
@@ -62,10 +62,19 @@ func HTTPUploadAndRedirectTo(t *testing.T, handler http.HandlerFunc, url, conten
 	isRedirectCode := code >= http.StatusMultipleChoices && code <= http.StatusTemporaryRedirect
 	assert.True(t, isRedirectCode, "Expected HTTP redirect status code for %q but received %d", url, code)
 	headers := w.Result().Header["Location"]
-	assert.True(t, len(headers) == 1 && headers[0] == destination,
-		"Expected HTTP redirect location %s for %q but received %v", destination, url, headers)
-	return isRedirectCode
+	assert.True(t, len(headers) == 1, "Expected a single redirect header but got %d locations", len(headers))
+	return headers[0]
 }
+
+// HTTPUploadAndRedirectTo checks that the request results in a redirect and it
+// checks the destination of the redirect. It returns whether the
+// request did in fact result in a redirect.
+func HTTPUploadAndRedirectTo(t *testing.T, handler http.HandlerFunc, url, contentType string, body *bytes.Buffer, destination string) {
+	location := HTTPUploadLocation(t, handler, url, contentType, body)
+	assert.Equal(t, destination, location,
+		"Expected HTTP redirect location %s for %q but received %s", destination, url, location)
+}
+
 // HTTPStatusCodeIfModifiedSince checks that the request results in a
 // 304 response for the given time.
 func HTTPStatusCodeIfModifiedSince(t *testing.T, handler http.HandlerFunc, url string, ti time.Time) {
@@ -76,3 +85,70 @@ func HTTPStatusCodeIfModifiedSince(t *testing.T, handler http.HandlerFunc, url s
 	handler(w, req)
 	assert.Equal(t, http.StatusNotModified, w.Code)
 }
+
+// restore remembers the file content before the test starts and restores the file at the end. Important for files such
+// as "index.md".
+func restore(t *testing.T, files ...string) {
+	data := make(map[string][]byte)
+	stat := make(map[string]os.FileInfo)
+	for _, file := range files {
+		s, err := os.Stat(file)
+		if err != nil {
+			t.Log("Could not stat ", file, ": ", err)
+			continue
+		}
+		c, err := os.ReadFile(file)
+		if err != nil {
+			t.Log("Could not read ", file, ": ", err)
+			continue
+		}
+		stat[file] = s
+		data[file] = c
+
+	}
+	t.Cleanup(func() {
+		for file, c := range data {
+			m := stat[file].Mode()
+			err := os.WriteFile(file, c, m)
+			if err != nil {
+				t.Log("Could not restore ", file, ": ", err)
+			}
+			t := stat[file].ModTime()
+			os.Chtimes(file, t, t)
+		}
+	})
+}
+
+// cleanup deletes any directories mentioned and removes all pages in those directories from the index. Incidentally, if
+// a filename such as "changes.md" or "changes.md~" is provided instead of a directory, then that page file is removed
+// and any mention of it is removed from the index.
+func cleanup(t *testing.T, dirs ...string) {
+	t.Cleanup(func() {
+		for _, dir := range dirs {
+			_ = os.RemoveAll(dir)
+		}
+		index.Lock()
+		defer index.Unlock()
+		for name := range index.titles {
+			for _, dir := range dirs {
+				if strings.HasPrefix(name, dir) {
+					delete(index.titles, name)
+				}
+			}
+		}
+		ids := []docid{}
+		for id, name := range index.documents {
+			for _, dir := range dirs {
+				if strings.HasPrefix(name, dir) {
+					delete(index.documents, id)
+					ids = append(ids, id)
+				}
+			}
+		}
+		for hashtag, docs := range index.token {
+			index.token[hashtag] = slices.DeleteFunc(ids, func(id docid) bool {
+				return slices.Contains(docs, id)
+			})
+		}
+	})
+}