Merge remote-tracking branch 'origin/feature/thumbnails' into feature/thumbnails

# Conflicts:
#	frontend/.eslintrc.js
#	frontend/src/components/files/ListingItem.vue
#	frontend/src/components/files/Preview.vue
#	http/http.go

go.mod

@@ -17,6 +17,7 @@ require (
 	github.com/maruel/natural v0.0.0-20180416170133-dbcb3e2e8cf1
 	github.com/mholt/archiver v3.1.1+incompatible
 	github.com/mitchellh/go-homedir v1.1.0
+	github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646
 	github.com/nwaples/rardecode v1.0.0 // indirect
 	github.com/pelletier/go-toml v1.6.0
 	github.com/pierrec/lz4 v0.0.0-20190131084431-473cd7ce01a1 // indirect

go.sum

@@ -143,6 +143,8 @@ github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh
 github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
 github.com/naoina/go-stringutil v0.1.0/go.mod h1:XJ2SJL9jCtBh+P9q5btrd/Ylo8XwT/h1USek5+NqSA0=
 github.com/naoina/toml v0.1.1/go.mod h1:NBIhNtsFMo3G2szEBne+bO4gS192HuIYRqfvOWb4i1E=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/nkovacs/streamquote v0.0.0-20170412213628-49af9bddb229 h1:E2B8qYyeSgv5MXpmzZXRNp8IAQ4vjxIjhpAf5hv/tAg=
 github.com/nkovacs/streamquote v0.0.0-20170412213628-49af9bddb229/go.mod h1:0aYXnNPJ8l7uZxf45rWW1a/uME32OF0rhiYGNQ2oF2E=
 github.com/nwaples/rardecode v1.0.0 h1:r7vGuS5akxOnR4JQSkko62RJ1ReCMXxQRPtxsiFMBOs=

http/preview.go

@@ -0,0 +1,126 @@
+package http
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"github.com/filebrowser/filebrowser/v2/files"
+	"github.com/nfnt/resize"
+	"image"
+	"image/gif"
+	"image/jpeg"
+	"image/png"
+	"io"
+	"mime"
+	"net/http"
+	"net/url"
+)
+
+var compressHandler = withUser(func(w http.ResponseWriter, r *http.Request, d *data) (int, error) {
+	if !d.user.Perm.Download {
+		return http.StatusAccepted, nil
+	}
+
+	file, err := files.NewFileInfo(files.FileOptions{
+		Fs:      d.user.Fs,
+		Path:    r.URL.Path,
+		Modify:  d.user.Perm.Modify,
+		Expand:  true,
+		Checker: d,
+	})
+	if err != nil {
+		return errToStatus(err), err
+	}
+
+	if file.IsDir || file.Type != "image" {
+		return http.StatusNotFound, nil
+	}
+
+	return compressFileHandler(w, r, file)
+})
+
+func compressFileHandler(w http.ResponseWriter, r *http.Request, file *files.FileInfo) (int, error) {
+	fd, err := file.Fs.Open(file.Path)
+	if err != nil {
+		return http.StatusInternalServerError, err
+	}
+	defer fd.Close()
+
+	if r.URL.Query().Get("inline") == "true" {
+		w.Header().Set("Content-Disposition", "inline")
+	} else {
+		// As per RFC6266 section 4.3
+		w.Header().Set("Content-Disposition", "attachment; filename*=utf-8''"+url.PathEscape(file.Name))
+	}
+
+	buf, err := compressImageHandler(file, fd)
+	if err != nil {
+		return errToStatus(err), err
+	}
+	w.Header().Add("Content-Length", fmt.Sprintf("%d", buf.Len()))
+	w.Header().Add("Content-Type", mime.TypeByExtension(file.Extension))
+	io.Copy(w, buf)
+	return 0, nil
+}
+
+func compressImageHandler(file *files.FileInfo, fd io.Reader) (*bytes.Buffer, error) {
+	var (
+		buf *bytes.Buffer
+		m   image.Image
+		err error
+	)
+
+	switch file.Extension {
+	case ".jpg", ".jpeg":
+		buf, m, err = compressImage(jpeg.Decode, fd)
+		if err != nil {
+			return nil, err
+		}
+		err = jpeg.Encode(buf, m, nil)
+		break
+	case ".png":
+		buf, m, err = compressImage(png.Decode, fd)
+		if err != nil {
+			return nil, err
+		}
+		err = png.Encode(buf, m)
+		break
+	case ".gif":
+		buf, m, err = compressImage(gif.Decode, fd)
+		if err != nil {
+			return nil, err
+		}
+		err = gif.Encode(buf, m, nil)
+		break
+	default:
+		return nil, errors.New("extension is not supported")
+	}
+	if err != nil {
+		return nil, err
+	}
+	return buf, nil
+}
+
+const maxSize = 1080
+
+func compressImage(decode func(r io.Reader) (image.Image, error), fd io.Reader) (*bytes.Buffer, image.Image, error) {
+	img, err := decode(fd)
+	if err != nil {
+		return nil, nil, err
+	}
+	buf := bytes.NewBuffer([]byte{})
+	width := img.Bounds().Dx()
+	height := img.Bounds().Dy()
+	if width > maxSize && width > height {
+		width = maxSize
+		height = 0
+	} else if height > maxSize && height > width {
+		width = 0
+		height = maxSize
+	} else {
+		width = 0
+		height = 0
+	}
+	m := resize.Resize(uint(width), uint(height), img, resize.Lanczos3)
+	return buf, m, nil
+}