add paging support to playlists

mopidy_youtube/backend.py

@@ -38,7 +38,8 @@ class YouTubeBackend(pykka.ThreadingActor, backend.Backend):
 class YouTubeLibraryProvider(backend.LibraryProvider):
 
     def _get_duration(self, yttime):
-        # convert PT1H2M10S to 3730
+        """Convert youtube time to milliseconds"""
+        # convert PT1H2M10S to 3730000
         m = re.search('PT((?P<hours>\d+)H)?' +
                       '((?P<minutes>\d+)M)?' +
                       '((?P<seconds>\d+)S)?',
@@ -48,7 +49,7 @@ class YouTubeLibraryProvider(backend.LibraryProvider):
                 int(m.group('seconds') or 0)) * 1000
 
     def _get_videos(self, ids):
-        """Get list of youtube ids and return tracks"""
+        """Process youtube ids and return tracks"""
         logger.info("Get videos for '%s'", str(ids))
         query = {
             'part': 'id,snippet,contentDetails',
@@ -73,21 +74,28 @@ class YouTubeLibraryProvider(backend.LibraryProvider):
             tracks.append(track)
         return tracks
 
-    def _get_playlist(self, id, maxresults=30):
+    def _get_playlist(self, id, maxresults=100):
+        """Process youtube playlist and return tracks"""
         logger.info("Get Playlist for '%s'", str(id))
-        query = {
-            'part': 'id,snippet',
-            'fields': 'nextPageToken,items(snippet(resourceId(videoId)))',
-            'maxResults': maxresults,
-            'playlistId': id,
-            'key': yt_key,
-            'pageToken': '',
-        }
-        results = session.get(yt_api_endpoint + 'playlistItems', params=query).json()['items']
-        videoids = [x['snippet']['resourceId']['videoId'] for x in results]
+        page = ''
+        videoids = []
+        while page is not None and len(videoids) < maxresults:
+            query = {
+                'part': 'id,snippet',
+                'fields': 'nextPageToken,items(snippet(resourceId(videoId)))',
+                'maxResults': maxresults,
+                'playlistId': id,
+                'key': yt_key,
+                'pageToken': page,
+            }
+            results = session.get(yt_api_endpoint + 'playlistItems', params=query).json()['items']
+            videoids += [x['snippet']['resourceId']['videoId'] for x in results]
+            page = results['nextPageToken'] or None
+
         return self._get_videos(videoids)
 
     def _get_search(self, query, maxresults=20):
+        """Process youtube search and return tracks"""
         query = {
             'part': 'id',
             'fields': 'items(id)',
@@ -102,6 +110,7 @@ class YouTubeLibraryProvider(backend.LibraryProvider):
         return self._get_videos(videoids)
 
     def lookup(self, uri):
+        """Process youtube playlist or id and return tracks"""
         logger.info("Looking up YouTube for '%s'", uri)
         for scheme in self.backend.uri_schemes:
             if uri.startswith(scheme):
@@ -118,6 +127,7 @@ class YouTubeLibraryProvider(backend.LibraryProvider):
             return self._get_videos([uri])
 
     def search(self, query=None, uris=None, exact=False):
+        """Search for query in youtube and return tracks"""
         # TODO Support exact search
         logger.info("Searching YouTube for query '%s'", query)
 
@@ -136,6 +146,7 @@ class YouTubeLibraryProvider(backend.LibraryProvider):
 class YouTubePlaybackProvider(backend.PlaybackProvider):
 
     def translate_uri(self, uri):
+        """Translate youtube video url or id into ressource url"""
         logger.info("Playing YouTube id: %s" % uri)
         for scheme in self.backend.uri_schemes:
             if uri.startswith(scheme):