Files
oddmu/html_cmd.go
2025-12-06 14:10:20 +01:00

91 lines
2.3 KiB
Go

package main
import (
"context"
"flag"
"fmt"
"html/template"
"io"
"os"
"strings"
"github.com/google/subcommands"
)
type htmlCmd struct {
template string
}
func (*htmlCmd) Name() string { return "html" }
func (*htmlCmd) Synopsis() string { return "render a page as HTML" }
func (*htmlCmd) Usage() string {
return `html [-template <template name>] <page name> ...:
Render one or more pages as HTML.
Use a single - to read Markdown from stdin.
`
}
func (cmd *htmlCmd) SetFlags(f *flag.FlagSet) {
f.StringVar(&cmd.template, "template", "",
"use the given HTML file as a template (probably view.html or static.html).")
}
func (cmd *htmlCmd) Execute(_ context.Context, f *flag.FlagSet, _ ...interface{}) subcommands.ExitStatus {
return htmlCli(os.Stdout, cmd.template, f.Args())
}
func htmlCli(w io.Writer, template string, args []string) subcommands.ExitStatus {
if len(args) == 1 && args[0] == "-" {
body, err := io.ReadAll(os.Stdin)
if err != nil {
fmt.Fprintf(w, "Cannot read from stdin: %s\n", err)
return subcommands.ExitFailure
}
p := &Page{Name: "stdin", Body: body}
return p.printHTML(w, template)
}
for _, name := range args {
if !strings.HasSuffix(name, ".md") {
fmt.Fprintf(os.Stderr, "%s does not end in '.md'\n", name)
return subcommands.ExitFailure
}
name = name[0 : len(name)-3]
p, err := loadPage(name)
if err != nil {
fmt.Fprintf(os.Stderr, "Cannot load %s: %s\n", name, err)
return subcommands.ExitFailure
}
status := p.printHTML(w, template)
if status != subcommands.ExitSuccess {
return status
}
}
return subcommands.ExitSuccess
}
func (p *Page) printHTML(w io.Writer, fn string) subcommands.ExitStatus {
if fn == "" {
// do not handle title
p.renderHTML()
_, err := fmt.Fprintln(w, p.HTML)
if err != nil {
fmt.Fprintf(os.Stderr, "Cannot write to stdout: %s\n", err)
return subcommands.ExitFailure
}
return subcommands.ExitSuccess
}
p.handleTitle(true)
p.renderHTML()
t, err := template.ParseFiles(fn)
if err != nil {
fmt.Fprintf(os.Stderr, "Cannot parse template %s for %s: %s\n", fn, p.Name, err)
return subcommands.ExitFailure
}
err = t.Execute(w, p)
if err != nil {
fmt.Fprintf(os.Stderr, "Cannot execute template %s for %s: %s\n", fn, p.Name, err)
return subcommands.ExitFailure
}
return subcommands.ExitSuccess
}