Update stored playlists controller to support backends without playlists

mopidy/core/stored_playlists.py

@@ -18,7 +18,8 @@ class StoredPlaylistsController(object):
 
         Read-only. List of :class:`mopidy.models.Playlist`.
         """
-        futures = [b.stored_playlists.playlists for b in self.backends]
+        futures = [b.stored_playlists.playlists
+            for b in self.backends.with_stored_playlists]
         results = pykka.get_all(futures)
         return list(itertools.chain(*results))
 
@@ -40,10 +41,10 @@ class StoredPlaylistsController(object):
         :type uri_scheme: string
         :rtype: :class:`mopidy.models.Playlist`
         """
-        if uri_scheme in self.backends.by_uri_scheme:
+        if uri_scheme in self.backends.with_stored_playlists_by_uri_scheme:
             backend = self.backends.by_uri_scheme[uri_scheme]
         else:
-            backend = self.backends[0]
+            backend = self.backends.with_stored_playlists[0]
         return backend.stored_playlists.create(name).get()
 
     def delete(self, uri):
@@ -57,8 +58,9 @@ class StoredPlaylistsController(object):
         :type uri: string
         """
         uri_scheme = urlparse.urlparse(uri).scheme
-        if uri_scheme in self.backends.by_uri_scheme:
-            backend = self.backends.by_uri_scheme[uri_scheme]
+        backend = self.backends.with_stored_playlists_by_uri_scheme.get(
+            uri_scheme, None)
+        if backend:
             backend.stored_playlists.delete(uri).get()
 
     def get(self, **criteria):
@@ -101,7 +103,8 @@ class StoredPlaylistsController(object):
         :rtype: :class:`mopidy.models.Playlist` or :class:`None`
         """
         uri_scheme = urlparse.urlparse(uri).scheme
-        backend = self.backends.by_uri_scheme.get(uri_scheme, None)
+        backend = self.backends.with_stored_playlists_by_uri_scheme.get(
+            uri_scheme, None)
         if backend:
             return backend.stored_playlists.lookup(uri).get()
         else:
@@ -120,11 +123,13 @@ class StoredPlaylistsController(object):
         :type uri_scheme: string
         """
         if uri_scheme is None:
-            futures = [b.stored_playlists.refresh() for b in self.backends]
+            futures = [b.stored_playlists.refresh()
+                for b in self.backends.with_stored_playlists]
             pykka.get_all(futures)
         else:
-            if uri_scheme in self.backends.by_uri_scheme:
-                backend = self.backends.by_uri_scheme[uri_scheme]
+            backend = self.backends.with_stored_playlists_by_uri_scheme.get(
+                uri_scheme, None)
+            if backend:
                 backend.stored_playlists.refresh().get()
 
     def save(self, playlist):
@@ -152,7 +157,7 @@ class StoredPlaylistsController(object):
         if playlist.uri is None:
             return
         uri_scheme = urlparse.urlparse(playlist.uri).scheme
-        if uri_scheme not in self.backends.by_uri_scheme:
-            return
-        backend = self.backends.by_uri_scheme[uri_scheme]
-        return backend.stored_playlists.save(playlist).get()
+        backend = self.backends.with_stored_playlists_by_uri_scheme.get(
+            uri_scheme, None)
+        if backend:
+            return backend.stored_playlists.save(playlist).get()

tests/core/stored_playlists_test.py

@@ -19,6 +19,12 @@ class StoredPlaylistsTest(unittest.TestCase):
         self.sp2 = mock.Mock(spec=base.BaseStoredPlaylistsProvider)
         self.backend2.stored_playlists = self.sp2
 
+        # A backend without the optional stored playlists provider
+        self.backend3 = mock.Mock()
+        self.backend3.uri_schemes.get.return_value = ['dummy3']
+        self.backend3.has_stored_playlists().get.return_value = False
+        self.backend3.stored_playlists = None
+
         self.pl1a = Playlist(tracks=[Track(uri='dummy1:a')])
         self.pl1b = Playlist(tracks=[Track(uri='dummy1:b')])
         self.sp1.playlists.get.return_value = [self.pl1a, self.pl1b]
@@ -27,7 +33,8 @@ class StoredPlaylistsTest(unittest.TestCase):
         self.pl2b = Playlist(tracks=[Track(uri='dummy2:b')])
         self.sp2.playlists.get.return_value = [self.pl2a, self.pl2b]
 
-        self.core = Core(audio=None, backends=[self.backend1, self.backend2])
+        self.core = Core(audio=None, backends=[
+            self.backend3, self.backend1, self.backend2])
 
     def test_get_playlists_combines_result_from_backends(self):
         result = self.core.stored_playlists.playlists
@@ -59,6 +66,17 @@ class StoredPlaylistsTest(unittest.TestCase):
         self.assertFalse(self.sp1.create.called)
         self.sp2.create.assert_called_once_with('foo')
 
+    def test_create_with_unsupported_uri_scheme_uses_first_backend(self):
+        playlist = Playlist()
+        self.sp1.create().get.return_value = playlist
+        self.sp1.reset_mock()
+
+        result = self.core.stored_playlists.create('foo', uri_scheme='dummy3')
+
+        self.assertEqual(playlist, result)
+        self.sp1.create.assert_called_once_with('foo')
+        self.assertFalse(self.sp2.create.called)
+
     def test_delete_selects_the_dummy1_backend(self):
         self.core.stored_playlists.delete('dummy1:a')
 
@@ -77,6 +95,12 @@ class StoredPlaylistsTest(unittest.TestCase):
         self.assertFalse(self.sp1.delete.called)
         self.assertFalse(self.sp2.delete.called)
 
+    def test_delete_ignores_backend_without_playlist_support(self):
+        self.core.stored_playlists.delete('dummy3:a')
+
+        self.assertFalse(self.sp1.delete.called)
+        self.assertFalse(self.sp2.delete.called)
+
     def test_lookup_selects_the_dummy1_backend(self):
         self.core.stored_playlists.lookup('dummy1:a')
 
@@ -89,6 +113,13 @@ class StoredPlaylistsTest(unittest.TestCase):
         self.assertFalse(self.sp1.lookup.called)
         self.sp2.lookup.assert_called_once_with('dummy2:a')
 
+    def test_lookup_track_in_backend_without_playlists_fails(self):
+        result = self.core.stored_playlists.lookup('dummy3:a')
+
+        self.assertIsNone(result)
+        self.assertFalse(self.sp1.lookup.called)
+        self.assertFalse(self.sp2.lookup.called)
+
     def test_refresh_without_uri_scheme_refreshes_all_backends(self):
         self.core.stored_playlists.refresh()
 
@@ -107,6 +138,12 @@ class StoredPlaylistsTest(unittest.TestCase):
         self.assertFalse(self.sp1.refresh.called)
         self.assertFalse(self.sp2.refresh.called)
 
+    def test_refresh_ignores_backend_without_playlist_support(self):
+        self.core.stored_playlists.refresh(uri_scheme='dummy3')
+
+        self.assertFalse(self.sp1.refresh.called)
+        self.assertFalse(self.sp2.refresh.called)
+
     def test_save_selects_the_dummy1_backend(self):
         playlist = Playlist(uri='dummy1:a')
         self.sp1.save().get.return_value = playlist
@@ -142,3 +179,10 @@ class StoredPlaylistsTest(unittest.TestCase):
         self.assertIsNone(result)
         self.assertFalse(self.sp1.save.called)
         self.assertFalse(self.sp2.save.called)
+
+    def test_save_ignores_backend_without_playlist_support(self):
+        result = self.core.stored_playlists.save(Playlist(uri='dummy3:a'))
+
+        self.assertIsNone(result)
+        self.assertFalse(self.sp1.save.called)
+        self.assertFalse(self.sp2.save.called)