Fix #1031: Add get_images() to local library.

docs/changelog.rst

@@ -88,6 +88,9 @@ v0.20.0 (UNRELEASED)
 
 - Sort local playlists by name. (Fixes: :issue:`1026`, PR: :issue:`1028`)
 
+- Add :meth:`mopidy.local.Library.get_images` for looking up images
+  for local URIs. (Fixes: :issue:`1031`, PR: :issue:`1032`)
+
 **File scanner**
 
 - Improve error logging for scan code (Fixes: :issue:`856`, PR: :issue:`874`)

mopidy/local/__init__.py

@@ -4,7 +4,7 @@ import logging
 import os
 
 import mopidy
-from mopidy import config, ext
+from mopidy import config, ext, models
 
 logger = logging.getLogger(__name__)
 
@@ -101,6 +101,27 @@ class Library(object):
         """
         return set()
 
+    def get_images(self, uris):
+        """
+        Lookup the images for the given URIs.
+
+        The default implementation will simply call :meth:`lookup` and
+        try and use the album art for any tracks returned. Most local
+        libraries should replace this with something smarter or simply
+        return an empty dictionary.
+
+        :param list uris: list of URIs to find images for
+        :rtype: {uri: tuple of :class:`mopidy.models.Image`}
+        """
+        result = {}
+        for uri in uris:
+            image_uris = set()
+            for track in self.lookup(uri):
+                if track.album and track.album.images:
+                    image_uris.update(track.album.images)
+            result[uri] = [models.Image(uri=u) for u in image_uris]
+        return result
+
     def load(self):
         """
         (Re)load any tracks stored in memory, if any, otherwise just return

mopidy/local/library.py

@@ -28,6 +28,11 @@ class LocalLibraryProvider(backend.LibraryProvider):
             return set()
         return self._library.get_distinct(field, query)
 
+    def get_images(self, uris):
+        if not self._library:
+            return {}
+        return self._library.get_images(uris)
+
     def refresh(self, uri=None):
         if not self._library:
             return 0

tests/local/test_library.py

@@ -11,7 +11,7 @@ import pykka
 
 from mopidy import core
 from mopidy.local import actor, json
-from mopidy.models import Album, Artist, Track
+from mopidy.models import Album, Artist, Image, Track
 
 from tests import path_to_data_dir
 
@@ -580,3 +580,30 @@ class LocalLibraryProviderTest(unittest.TestCase):
 
         with self.assertRaises(LookupError):
             self.library.search(any=[''])
+
+    def test_default_get_images_impl_no_images(self):
+        result = self.library.get_images([track.uri for track in self.tracks])
+        self.assertEqual(result, {track.uri: tuple() for track in self.tracks})
+
+    @mock.patch.object(json.JsonLibrary, 'lookup')
+    def test_default_get_images_impl_album_images(self, mock_lookup):
+        library = actor.LocalBackend(config=self.config, audio=None).library
+
+        image = Image(uri='imageuri')
+        album = Album(images=[image.uri])
+        track = Track(uri='trackuri', album=album)
+        mock_lookup.return_value = [track]
+
+        result = library.get_images([track.uri])
+        self.assertEqual(result, {track.uri: [image]})
+
+    @mock.patch.object(json.JsonLibrary, 'get_images')
+    def test_local_library_get_images(self, mock_get_images):
+        library = actor.LocalBackend(config=self.config, audio=None).library
+
+        image = Image(uri='imageuri')
+        track = Track(uri='trackuri')
+        mock_get_images.return_value = {track.uri: [image]}
+
+        result = library.get_images([track.uri])
+        self.assertEqual(result, {track.uri: [image]})