Add skel for preview generator for ggs

Co-authored-by: Ralf Haferkamp <rhafer@owncloud.com>

Signed-off-by: Christian Richter <crichter@owncloud.com>

services/app-registry/pkg/config/defaults/defaultconfig.go

@@ -111,6 +111,12 @@ func defaultMimeTypeConfig() []config.MimeTypeConfig {
 			Name:        "Compressed markdown file",
 			Description: "Compressed markdown file",
 		},
+		{
+			MimeType:    "application/vnd.geogebra.slides",
+			Extension:   "ggs",
+			Name:        "GeoGebra Slides",
+			Description: "GeoGebra Slides",
+		},
 	}
 }
 

services/thumbnails/pkg/thumbnail/encoding.go

@@ -15,6 +15,7 @@ const (
 	typeJpg  = "jpg"
 	typeJpeg = "jpeg"
 	typeGif  = "gif"
+	typeGgs  = "ggs"
 )
 
 var (
@@ -119,6 +120,8 @@ func GetExtForMime(fileType string) string {
 	switch ext {
 	case typeJpg, typeJpeg, typePng, typeGif:
 		return ext
+	case "application/vnd.geogebra.slides":
+		return typeGgs
 	default:
 		return ""
 	}

services/thumbnails/pkg/thumbnail/generator.go

@@ -71,6 +71,14 @@ func (g GifGenerator) imageToPaletted(img image.Image, p color.Palette) *image.P
 	return pm
 }
 
+// GgsGenerator is used to create a web friendly version of the provided ggs image.
+type GgsGenerator struct{}
+
+func (g GgsGenerator) Generate(size image.Rectangle, img interface{}, processor Processor) (interface{}, error) {
+	// TODO: write zip extractor, get image from zip, process image, return image
+	return nil, nil
+}
+
 // GeneratorForType returns the generator for a given file type
 // or nil if the type is not supported.
 func GeneratorForType(fileType string) (Generator, error) {
@@ -79,6 +87,8 @@ func GeneratorForType(fileType string) (Generator, error) {
 		return SimpleGenerator{}, nil
 	case typeGif:
 		return GifGenerator{}, nil
+	case typeGgs:
+		return GgsGenerator{}, nil
 	default:
 		return nil, ErrNoEncoderForType
 	}

services/web/pkg/config/defaults/defaultconfig.go

@@ -106,14 +106,13 @@ func DefaultConfig() *config.Config {
 								"image/tiff",
 								"image/bmp",
 								"image/x-ms-bmp",
-								"application/vnd.geogebra.slides",
 							},
 						},
 					},
 				},
 				Options: config.Options{
 					ContextHelpersReadMore:   true,
-					PreviewFileMimeTypes:     []string{"image/gif", "image/png", "image/jpeg", "text/plain", "image/tiff", "image/bmp", "image/x-ms-bmp"},
+					PreviewFileMimeTypes:     []string{"image/gif", "image/png", "image/jpeg", "text/plain", "image/tiff", "image/bmp", "image/x-ms-bmp", "application/vnd.geogebra.slides"},
 					SharingRecipientsPerPage: 200,
 					AccountEditLink:          &config.AccountEditLink{},
 					Editor:                   &config.Editor{},