Add minimal play and stop support for gstreamer

mopidy/backends/gstreamer.py

@@ -1,5 +1,7 @@
 import logging
 
+import gst
+
 from mopidy import config
 from mopidy.backends import BaseBackend
 from mopidy.models import Artist, Album, Track, Playlist
@@ -7,4 +9,30 @@ from mopidy.models import Artist, Album, Track, Playlist
 logger = logging.getLogger(u'backends.gstreamer')
 
 class GStreamerBackend(BaseBackend):
-    pass
+    def __init__(self, *args, **kwargs):
+        super(GStreamerBackend, self).__init__(*args, **kwargs)
+
+        playlist = []
+        player = gst.element_factory_make("playbin2", "player")
+        fakesink = gst.element_factory_make("fakesink", "fakesink")
+
+        player.set_property("video-sink", fakesink)
+
+        self.player = player
+
+
+    def _play_current_track(self):
+        self.player.set_property("uri", self._current_track.uri)
+        self.player.set_state(gst.STATE_PLAYING)
+
+    def _play(self):
+        if self._current_track is not None:
+            self._play_current_track()
+            return True
+        else:
+            return False
+
+    def _stop(self):
+        self.player.set_state(gst.STATE_NULL)
+
+        return True