feat(webdav): extract thumbnails through Tika

.woodpecker.star

@@ -8,7 +8,7 @@ docker_repo_slug = "opencloudeu/opencloud"
 
 # images
 ALPINE_GIT = "alpine/git:latest"
-APACHE_TIKA = "apache/tika:4.0.0-full"
+APACHE_TIKA = "apache/tika:4.1.0-full"
 CHKO_DOCKER_PUSHRM = "chko/docker-pushrm:1"
 CODACY_COVERAGE_REPORTER = "codacy/codacy-coverage-reporter:14.1.3"
 COLLABORA_CODE = "collabora/code:24.04.5.1.1"
@@ -3447,6 +3447,17 @@ def tikaService():
         # tika 4 discovers its plugins relative to the image working directory,
         # the workspace default would leave the pipes fetchers empty
         "directory": "/opt/tika-server",
+        # the thumbnail preset ships inert; the config is what activates it
+        "entrypoint": [
+            "java",
+            "-cp",
+            "/opt/tika-server/*:/opt/tika-server/lib/*:/tika-extras/*",
+            "org.apache.tika.server.core.TikaServerCli",
+            "-h",
+            "0.0.0.0",
+            "-c",
+            "%s/tests/config/woodpecker/tika-config.json" % dirs["base"],
+        ],
         "detach": True,
     }, {
         "name": "wait-for-tika-service",

devtools/deployments/opencloud_full/config/tika/tika-config.json

@@ -0,0 +1,12 @@
+{
+  // -h and -p still come from the command line; a config file has to carry the block
+  "server": {
+    "port": 9998,
+    "host": "0.0.0.0"
+  },
+  // the thumbnail preset ships inert in tika-pipes-core; activating it is what serves
+  // PUT /unpack/preset/thumbnail, which the webdav thumbnailer asks for
+  "presets": {
+    "thumbnail": true
+  }
+}

devtools/deployments/opencloud_full/tika.yml

@@ -3,6 +3,10 @@ services:
   tika:
     image: ${TIKA_IMAGE:-apache/tika:latest-full}
     # release notes: https://tika.apache.org
+    # the thumbnail preset ships inert; the config is what activates it
+    command: ['-c', '/tika-config.json']
+    volumes:
+      - ./config/tika/tika-config.json:/tika-config.json
     networks:
       opencloud-net:
     restart: always
@@ -13,5 +17,6 @@ services:
     environment:
       # fulltext search
       SEARCH_EXTRACTOR_TYPE: tika
-      SEARCH_EXTRACTOR_TIKA_TIKA_URL: http://tika:9998
+      # the search extractor and the webdav thumbnailer both read it
+      OC_TIKA_URL: http://tika:9998
       FRONTEND_FULL_TEXT_SEARCH_ENABLED: "true"

services/search/README.md

@@ -107,7 +107,7 @@ As soon as Tika is installed and configured, the search service needs to be told
 The following settings must be set:
 
 *   `SEARCH_EXTRACTOR_TYPE=tika`
-*   `SEARCH_EXTRACTOR_TIKA_TIKA_URL=http://YOUR-TIKA.URL`
+*   `SEARCH_EXTRACTOR_TIKA_TIKA_URL=http://YOUR-TIKA.URL` (or the shared `OC_TIKA_URL`, which the webdav service reads for thumbnails too)
 
 Additionally, the following optional settings can be set:
 

services/search/pkg/config/content.go

@@ -9,6 +9,6 @@ type Extractor struct {
 
 // ExtractorTika configures the Tika extractor
 type ExtractorTika struct {
-	TikaURL        string `yaml:"tika_url" env:"SEARCH_EXTRACTOR_TIKA_TIKA_URL" desc:"URL of the tika server." introductionVersion:"1.0.0"`
+	TikaURL        string `yaml:"tika_url" env:"OC_TIKA_URL;SEARCH_EXTRACTOR_TIKA_TIKA_URL" desc:"URL of the tika server." introductionVersion:"1.0.0"`
 	CleanStopWords bool   `yaml:"clean_stop_words" env:"SEARCH_EXTRACTOR_TIKA_CLEAN_STOP_WORDS" desc:"Defines if stop words should be cleaned or not. See the documentation for more details." introductionVersion:"1.0.0"`
 }

services/webdav/README.md

@@ -10,6 +10,8 @@
 
 The webdav service provides various `GET` endpoints to get the thumbnails of a file in authenticated and unauthenticated contexts. It also provides thumbnails for spaces on different endpoints.
 
+Thumbnails for documents, raw photos, audio cover art and other formats the webdav service cannot render itself come from an Apache Tika server (4.1 or newer) when `OC_TIKA_URL` (or `WEBDAV_TIKA_URL`) is set. Every file that is not a directly supported image is sent to Tika; `OC_TIKA_THUMBNAIL_MIME_TYPES` (or `WEBDAV_TIKA_THUMBNAIL_MIME_TYPES`) restricts that to a list of mime types, where an entry like `image/x-raw-samsung:image/x-samsung-srw` maps a type to the one Tika knows the format by. The webdav service calls `PUT /unpack/preset/thumbnail`, so the Tika server must activate the `thumbnail` catalog preset in its configuration (`"presets": {"thumbnail": true}`). Without Tika, audio cover art and GeoGebra thumbnails are still extracted by the webdav service itself; those built-in extractors are deprecated.
+
 Generated thumbnails are cached by the webdav service itself. The cache backend defaults to `file`, storing entries under `$OC_BASE_DATA_PATH/thumbnails/files` (override with `WEBDAV_THUMBNAIL_CACHE_BACKEND` and `WEBDAV_THUMBNAIL_CACHE_DIR`). Use the `s3` backend when running multiple instances behind a load balancer so they share one cache.
 
 #### Thumbnail Query String Parameters

services/webdav/pkg/config/config.go

@@ -38,6 +38,9 @@ type Config struct {
 	ThumbnailCacheS3AccessKey string   `yaml:"thumbnail_cache_s3_access_key" env:"WEBDAV_THUMBNAIL_CACHE_S3_ACCESS_KEY" desc:"S3 access key for thumbnail cache authentication." introductionVersion:"1.0.0"`
 	ThumbnailCacheS3SecretKey string   `yaml:"thumbnail_cache_s3_secret_key" env:"WEBDAV_THUMBNAIL_CACHE_S3_SECRET_KEY" desc:"S3 secret key for thumbnail cache authentication." introductionVersion:"1.0.0"`
 	FontMapFile               string   `yaml:"font_map_file" env:"WEBDAV_THUMBNAILS_TXT_FONTMAP_FILE;THUMBNAILS_TXT_FONTMAP_FILE" desc:"The path to a font map file for txt thumbnails." introductionVersion:"1.0.0"`
+	TikaURL                   string   `yaml:"tika_url" env:"OC_TIKA_URL;WEBDAV_TIKA_URL" desc:"URL of an Apache Tika server. When set, thumbnails are generated for documents, raw photos, audio cover art and other formats Tika can extract a preview from." introductionVersion:"%%NEXT%%"`
+	TikaThumbnailMimeTypes    []string `yaml:"tika_thumbnail_mime_types" env:"OC_TIKA_THUMBNAIL_MIME_TYPES;WEBDAV_TIKA_THUMBNAIL_MIME_TYPES" desc:"Restrict thumbnail generation via Tika to these mime types. Empty means all types that are not handled directly. An entry can map a type to the one Tika knows the format by, e.g. image/x-raw-samsung:image/x-samsung-srw." introductionVersion:"%%NEXT%%"`
+	ThumbnailFormats          []string `yaml:"thumbnail_formats" env:"OC_THUMBNAIL_FORMATS;WEBDAV_THUMBNAIL_FORMATS" desc:"The type a thumbnail is written in, per type of the image it is made from, as mime:mime entries, e.g. image/vnd.microsoft.icon:image/png. A type that is not listed, or one the generator cannot write, keeps the format of the image itself." introductionVersion:"%%NEXT%%"`
 
 	Context context.Context `yaml:"-"`
 }

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

@@ -1,6 +1,7 @@
 package defaults
 
 import (
+	"github.com/opencloud-eu/opencloud/services/webdav/pkg/thumbnail"
 	"path"
 	"strings"
 
@@ -48,6 +49,7 @@ func DefaultConfig() *config.Config {
 		ThumbnailGeneratorURL:     "http://127.0.0.1:9186",
 		ThumbnailGeneratorTimeout: "30s",
 		MaxInputFileSize:          "50MB",
+		ThumbnailFormats:          thumbnail.DefaultFormats,
 		ThumbnailCacheBackend:     "file",
 		ThumbnailCacheDir:         path.Join(cored.BaseDataPath(), "thumbnails", "files"),
 		ThumbnailResolutions: []string{

services/webdav/pkg/preprocessor/errors.go

@@ -3,7 +3,8 @@ package preprocessor
 import "errors"
 
 var (
-	ErrNoImageFromAudioFile                    = errors.New("preprocessor: could not extract image from audio file")
-	ErrNoConverterForExtractedImageFromGgsFile = errors.New("preprocessor: could not find converter for image extracted from ggs file")
+	ErrNoImageFromAudioFile                      = errors.New("preprocessor: could not extract image from audio file")
+	ErrNoConverterForExtractedImageFromGgsFile   = errors.New("preprocessor: could not find converter for image extracted from ggs file")
 	ErrNoConverterForExtractedImageFromAudioFile = errors.New("preprocessor: could not find converter for image extracted from audio file")
+	ErrNoThumbnail                               = errors.New("preprocessor: the document has no thumbnail")
 )

services/webdav/pkg/preprocessor/preprocessor.go

@@ -6,6 +6,7 @@ import (
 	"bytes"
 	"encoding/base64"
 	"encoding/json"
+	"github.com/opencloud-eu/opencloud/services/webdav/pkg/thumbnail"
 	"image"
 	"image/draw"
 	"image/gif"
@@ -39,7 +40,9 @@ func (i GifDecoder) Convert(r io.Reader) (any, error) {
 	return img, nil
 }
 
-// GgsDecoder is a converter for the geogebra slides file
+// GgsDecoder is a converter for the geogebra slides file.
+//
+// Deprecated: Tika provides the thumbnail; kept for setups without Tika.
 type GgsDecoder struct{ thumbnailpath string }
 
 // Convert reads the ggs file and returns the thumbnail image.
@@ -79,7 +82,9 @@ func (g GgsDecoder) Convert(r io.Reader) (any, error) {
 	return nil, errors.Errorf("%s not found", g.thumbnailpath)
 }
 
-// AudioDecoder is a converter for the audio file
+// AudioDecoder is a converter for the audio file.
+//
+// Deprecated: Tika provides the cover art; kept for setups without Tika.
 type AudioDecoder struct{}
 
 // Convert reads the audio file and extracts the thumbnail image from the id3 tag.
@@ -209,7 +214,9 @@ type GGPStruct struct {
 	}
 }
 
-// GgpDecoder is a converter for the geogebra pinboard file
+// GgpDecoder is a converter for the geogebra pinboard file.
+//
+// Deprecated: see GgsDecoder.
 type GgpDecoder struct{}
 
 // Convert reads the ggp file and returns the first thumbnail image.
@@ -313,6 +320,16 @@ func drawWord(canvas *font.Drawer, word string, minX, maxX, incY, maxY fixed.Int
 	}
 }
 
+// tikaOr prefers a configured Tika server, else the fallback
+func tikaOr(opts map[string]any, mimeType string, fallback FileConverter) FileConverter {
+	tika, _ := opts["tika"].(thumbnail.Tika)
+	if !tika.Supports(mimeType) {
+		return fallback
+	}
+	filename, _ := opts["filename"].(string)
+	return TikaThumbnail{tikaURL: tika.URL, filename: filename, contentType: tika.ContentType(mimeType)}
+}
+
 // ForType returns the converter for the specified mimeType
 func ForType(mimeType string, opts map[string]any) FileConverter {
 	// We can ignore the error here because we parse it in IsMimeTypeSupported before and if it fails
@@ -348,19 +365,22 @@ func ForType(mimeType string, opts map[string]any) FileConverter {
 		return TxtToImageConverter{
 			fontLoader: fontLoader,
 		}
-	case "application/vnd.geogebra.slides":
-		return GgsDecoder{"_slide0/geogebra_thumbnail.png"}
-	case "application/vnd.geogebra.pinboard":
-		return GgpDecoder{}
 	case "image/gif":
 		return GifDecoder{}
-	case "audio/flac":
-		fallthrough
-	case "audio/mpeg":
-		fallthrough
-	case "audio/ogg":
-		return AudioDecoder{}
+	case "application/vnd.geogebra.slides":
+		return tikaOr(opts, mimeType, GgsDecoder{"_slide0/geogebra_thumbnail.png"})
+	case "application/vnd.geogebra.pinboard":
+		return tikaOr(opts, mimeType, GgpDecoder{})
+	case "audio/flac", "audio/mpeg", "audio/ogg":
+		return tikaOr(opts, mimeType, AudioDecoder{})
 	default:
-		return ImageDecoder{}
+		return tikaOr(opts, mimeType, ImageDecoder{})
 	}
 }
+
+// Encoded is an image a converter hands on as it found it. The type decides
+// the format the thumbnail is written in.
+type Encoded struct {
+	ContentType string
+	Data        []byte
+}

services/webdav/pkg/preprocessor/tika.go

@@ -0,0 +1,125 @@
+package preprocessor
+
+import (
+	"archive/zip"
+	"bytes"
+	"fmt"
+	"io"
+	"mime"
+	"net/http"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+// maxTikaResponse bounds what is read back from Tika
+const maxTikaResponse = 100 * 1024 * 1024
+
+var tikaHTTPClient = &http.Client{Timeout: 60 * time.Second}
+
+// TikaThumbnail asks a Tika server for the document's thumbnail.
+type TikaThumbnail struct {
+	tikaURL string
+	// detection hints
+	filename    string
+	contentType string
+}
+
+// Convert hands the thumbnail on undecoded: the generator reads formats webdav
+// cannot, an .ico icon group out of a PE binary for one.
+func (t TikaThumbnail) Convert(r io.Reader) (any, error) {
+	data, err := io.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+
+	contentType, img, err := tikaThumbnail(t.tikaURL, t.filename, t.contentType, data)
+	if err != nil {
+		return nil, err
+	}
+
+	return Encoded{ContentType: contentType, Data: img}, nil
+}
+
+// tikaThumbnail returns the thumbnail Tika found in the document and its
+// content type. The thumbnail catalog preset (Tika 4.1, TIKA-4856) unpacks
+// exactly the raster image a client would show for the document — a stored
+// thumbnail such as a raw photo's embedded preview or an audio file's cover,
+// the rendering of an office document's metafile thumbnail, or the rendered
+// first page of a PDF — so the zip carries that one image and nothing else.
+func tikaThumbnail(tikaURL, filename, contentType string, data []byte) (string, []byte, error) {
+	if contentType == "" {
+		contentType = "application/octet-stream"
+	}
+	req, err := http.NewRequest(http.MethodPut, strings.TrimRight(tikaURL, "/")+"/unpack/preset/thumbnail", bytes.NewReader(data))
+	if err != nil {
+		return "", nil, err
+	}
+	req.Header.Set("Content-Type", contentType)
+	req.Header.Set("Accept", "application/zip")
+	// the extension is what routes a raw image to its parser
+	if filename != "" {
+		req.Header.Set("Content-Disposition", fmt.Sprintf("attachment; filename=%q", filename))
+	}
+
+	resp, err := tikaHTTPClient.Do(req)
+	if err != nil {
+		return "", nil, fmt.Errorf("tika request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	switch resp.StatusCode {
+	case http.StatusOK:
+	case http.StatusNoContent:
+		return "", nil, ErrNoThumbnail
+	case http.StatusNotFound:
+		// the route exists once the catalog preset is active
+		return "", nil, fmt.Errorf(`tika unpack returned %s: the "thumbnail" preset needs Tika >= 4.1 and "presets": {"thumbnail": true} in its config`, resp.Status)
+	default:
+		return "", nil, fmt.Errorf("tika unpack returned %s", resp.Status)
+	}
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, maxTikaResponse))
+	if err != nil {
+		return "", nil, fmt.Errorf("tika unpack response: %w", err)
+	}
+	zr, err := zip.NewReader(bytes.NewReader(body), int64(len(body)))
+	if err != nil {
+		return "", nil, fmt.Errorf("tika unpack response: %w", err)
+	}
+	return thumbnailFromZip(zr)
+}
+
+// thumbnailFromZip takes the one image the preset unpacked. Lenient about the
+// shape: the first regular file that is not a metadata sidecar wins.
+func thumbnailFromZip(zr *zip.Reader) (string, []byte, error) {
+	for _, f := range zr.File {
+		if f.FileInfo().IsDir() || strings.HasSuffix(f.Name, ".metadata.json") {
+			continue
+		}
+		img, err := readZipEntry(zr, f.Name)
+		if err != nil || len(img) == 0 {
+			return "", nil, ErrNoThumbnail
+		}
+		return entryContentType(f.Name, img), img, nil
+	}
+	return "", nil, ErrNoThumbnail
+}
+
+// entryContentType names the image's type. The preset zip carries no metadata
+// entries, so the extension decides and the bytes break the tie.
+func entryContentType(name string, data []byte) string {
+	if byExt := mime.TypeByExtension(filepath.Ext(name)); byExt != "" {
+		return byExt
+	}
+	return http.DetectContentType(data)
+}
+
+func readZipEntry(zr *zip.Reader, name string) ([]byte, error) {
+	rc, err := zr.Open(name)
+	if err != nil {
+		return nil, err
+	}
+	defer rc.Close()
+	return io.ReadAll(io.LimitReader(rc, maxTikaResponse))
+}