filebrowser/http/preview.go

95 lines
2.2 KiB
Go

package http
import (
"fmt"
"image"
"net/http"
"github.com/disintegration/imaging"
"github.com/gorilla/mux"
"github.com/filebrowser/filebrowser/v2/files"
)
const (
sizeThumb = "thumb"
sizeBig = "big"
)
type imageProcessor func(src image.Image) (image.Image, error)
var previewHandler = withUser(func(w http.ResponseWriter, r *http.Request, d *data) (int, error) {
if !d.user.Perm.Download {
return http.StatusAccepted, nil
}
vars := mux.Vars(r)
size := vars["size"]
if size != sizeBig && size != sizeThumb {
return http.StatusNotImplemented, nil
}
file, err := files.NewFileInfo(files.FileOptions{
Fs: d.user.Fs,
Path: "/" + vars["path"],
Modify: d.user.Perm.Modify,
Expand: true,
Checker: d,
})
if err != nil {
return errToStatus(err), err
}
setContentDisposition(w, r, file)
switch file.Type {
case "image":
return handleImagePreview(w, r, file, size)
default:
return http.StatusNotImplemented, fmt.Errorf("can't create preview for %s type", file.Type)
}
})
func handleImagePreview(w http.ResponseWriter, r *http.Request, file *files.FileInfo, size string) (int, error) {
format, err := imaging.FormatFromExtension(file.Extension)
if err != nil {
// Unsupported extensions directly return the raw data
if err == imaging.ErrUnsupportedFormat {
return rawFileHandler(w, r, file)
}
return errToStatus(err), err
}
var imgProcessor imageProcessor
switch size {
case sizeBig:
imgProcessor = func(img image.Image) (image.Image, error) {
return imaging.Fit(img, 1080, 1080, imaging.Lanczos), nil
}
case sizeThumb:
imgProcessor = func(img image.Image) (image.Image, error) {
return imaging.Thumbnail(img, 128, 128, imaging.Box), nil
}
default:
return http.StatusBadRequest, fmt.Errorf("unsupported preview size %s", size)
}
fd, err := file.Fs.Open(file.Path)
if err != nil {
return errToStatus(err), err
}
defer fd.Close()
img, err := imaging.Decode(fd, imaging.AutoOrientation(true))
if err != nil {
return errToStatus(err), err
}
img, err = imgProcessor(img)
if err != nil {
return errToStatus(err), err
}
if imaging.Encode(w, img, format) != nil {
return errToStatus(err), err
}
return 0, nil
}