filebrowser/http/preview.go
2020-07-27 19:26:44 +02:00

111 lines
2.5 KiB
Go

package http
import (
"context"
"errors"
"fmt"
"io"
"net/http"
"github.com/gorilla/mux"
"github.com/spf13/afero"
"github.com/filebrowser/filebrowser/v2/files"
"github.com/filebrowser/filebrowser/v2/img"
)
const (
sizeThumb = "thumb"
sizeBig = "big"
)
type ImgService interface {
FormatFromExtension(ext string) (img.Format, error)
Resize(ctx context.Context, file afero.File, width, height int, out io.Writer, options ...img.Option) error
}
func previewHandler(imgSvc ImgService) handleFunc {
return 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(imgSvc, w, r, file, size)
default:
return http.StatusNotImplemented, fmt.Errorf("can't create preview for %s type", file.Type)
}
})
}
func handleImagePreview(imgSvc ImgService, w http.ResponseWriter, r *http.Request, file *files.FileInfo, size string) (int, error) {
format, err := imgSvc.FormatFromExtension(file.Extension)
if err != nil {
// Unsupported extensions directly return the raw data
if err == img.ErrUnsupportedFormat {
return rawFileHandler(w, r, file)
}
return errToStatus(err), err
}
fd, err := file.Fs.Open(file.Path)
if err != nil {
return errToStatus(err), err
}
defer fd.Close()
if format == img.FormatGif && size == sizeBig {
if _, err := rawFileHandler(w, r, file); err != nil {
return errToStatus(err), err
}
return 0, nil
}
var (
width int
height int
options []img.Option
)
switch size {
case sizeBig:
width = 1080
height = 1080
options = append(options, img.WithHighPriority())
case sizeThumb:
width = 128
height = 128
options = append(options, img.WithMode(img.ResizeModeFill), img.WithQuality(img.QualityLow))
default:
return http.StatusBadRequest, fmt.Errorf("unsupported preview size %s", size)
}
if err := imgSvc.Resize(r.Context(), fd, width, height, w, options...); err != nil {
switch {
case errors.Is(err, context.DeadlineExceeded), errors.Is(err, context.Canceled):
default:
return 0, err
}
}
return 0, nil
}