Files
oddmu/upload_drop.go
2023-09-15 21:37:33 +02:00

113 lines
2.9 KiB
Go

package main
import (
"github.com/anthonynsimon/bild/imgio"
"github.com/anthonynsimon/bild/transform"
"image/jpeg"
"io"
"net/http"
"os"
"path"
"path/filepath"
"strconv"
"strings"
)
// uploadHandler uses the "upload.html" template to enable uploads.
// The file is saved using the saveUploadHandler.
func uploadHandler(w http.ResponseWriter, r *http.Request, dir string) {
renderTemplate(w, "upload", dir)
}
// dropHandler takes the "name" form field and the "file" form
// file and saves the file under the given name. The browser is
// redirected to the view of that file.
func dropHandler(w http.ResponseWriter, r *http.Request, dir string) {
d := path.Dir(dir)
// ensure the directory exists
fi, err := os.Stat(d)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
if !fi.IsDir() {
http.Error(w, "file exists", http.StatusInternalServerError)
return
}
name := r.FormValue("name")
filename := filepath.Base(name)
if filename == "." || filepath.Dir(name) != "." {
http.Error(w, "no filename", http.StatusInternalServerError)
return
}
file, _, err := r.FormFile("file")
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
defer file.Close()
// backup an existing file with the same name
_, err = os.Stat(filename)
if err != nil {
os.Rename(filename, filename+"~")
}
// create the new file
path := d + "/" + filename
dst, err := os.Create(path)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
defer dst.Close()
if _, err := io.Copy(dst, file); err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
// if a resize was requested
maxwidth := r.FormValue("maxwidth")
if len(maxwidth) > 0 {
mw, err := strconv.Atoi(maxwidth)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
ext := strings.ToLower(filepath.Ext(path))
var encoder imgio.Encoder
switch ext {
case ".png":
encoder = imgio.PNGEncoder()
case ".jpg", ".jpeg":
q := jpeg.DefaultQuality
quality := r.FormValue("quality")
if len(quality) > 0 {
q, err = strconv.Atoi(quality)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
}
encoder = imgio.JPEGEncoder(q)
default:
http.Error(w, "only .png, .jpg, or .jpeg files are supported", http.StatusInternalServerError)
return
}
img, err := imgio.Open(path)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
rect := img.Bounds()
width := rect.Max.X - rect.Min.X
if width > mw {
height := (rect.Max.Y - rect.Min.Y) * mw / width
img = transform.Resize(img, mw, height, transform.Linear)
if err := imgio.Save(path, img, encoder); err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
}
}
http.Redirect(w, r, "/view/"+path, http.StatusFound)
}