Test and implement mpris.Volume property

mopidy/frontends/mpris.py

@@ -15,6 +15,7 @@ from pykka.registry import ActorRegistry
 from mopidy.backends.base import Backend
 from mopidy.backends.base.playback import PlaybackController
 from mopidy.frontends.base import BaseFrontend
+from mopidy.mixers.base import BaseMixer
 
 logger = logging.getLogger('mopidy.frontends.mpris')
 
@@ -90,6 +91,7 @@ class MprisObject(dbus.service.Object):
 
     def __init__(self):
         self._backend = None
+        self._mixer = None
         self.properties = {
             ROOT_IFACE: self._get_root_iface_properties(),
             PLAYER_IFACE: self._get_player_iface_properties(),
@@ -121,8 +123,7 @@ class MprisObject(dbus.service.Object):
             'Metadata': ({
                 'mpris:trackid': '', # TODO Use (cpid, track.uri)
             }, None),
-            # TODO Get/set volume
-            'Volume': (1.0, None),
+            'Volume': (self.get_Volume, self.set_Volume),
             # TODO Get backend.playback.time_position
             'Position': (0, None),
             'MinimumRate': (1.0, None),
@@ -155,6 +156,14 @@ class MprisObject(dbus.service.Object):
             self._backend = backend_refs[0].proxy()
         return self._backend
 
+    @property
+    def mixer(self):
+        if self._mixer is None:
+            mixer_refs = ActorRegistry.get_by_class(BaseMixer)
+            assert len(mixer_refs) == 1, 'Expected exactly one running mixer.'
+            self._mixer = mixer_refs[0].proxy()
+        return self._mixer
+
 
     ### Properties interface
 
@@ -359,3 +368,18 @@ class MprisObject(dbus.service.Object):
             self.backend.playback.shuffle = True
         else:
             self.backend.playback.shuffle = False
+
+    def get_Volume(self):
+        volume = self.mixer.volume.get()
+        if volume is not None:
+            return volume / 100.0
+
+    def set_Volume(self, value):
+        if value is None:
+            return
+        elif value < 0:
+            self.mixer.volume = 0
+        elif value > 1:
+            self.mixer.volume = 100
+        elif 0 <= value <= 1:
+            self.mixer.volume = int(value * 100)

tests/frontends/mpris/player_interface_test.py

@@ -4,6 +4,7 @@ import unittest
 from mopidy.backends.dummy import DummyBackend
 from mopidy.backends.base.playback import PlaybackController
 from mopidy.frontends import mpris
+from mopidy.mixers.dummy import DummyMixer
 from mopidy.models import Track
 
 PLAYING = PlaybackController.PLAYING
@@ -13,12 +14,14 @@ STOPPED = PlaybackController.STOPPED
 class PlayerInterfaceTest(unittest.TestCase):
     def setUp(self):
         mpris.MprisObject._connect_to_dbus = mock.Mock()
+        self.mixer = DummyMixer.start().proxy()
         self.backend = DummyBackend.start().proxy()
         self.mpris = mpris.MprisObject()
         self.mpris._backend = self.backend
 
     def tearDown(self):
         self.backend.stop()
+        self.mixer.stop()
 
     def test_get_playback_status_is_playing_when_playing(self):
         self.backend.playback.state = PLAYING
@@ -107,6 +110,32 @@ class PlayerInterfaceTest(unittest.TestCase):
         result = self.mpris.Set(mpris.PLAYER_IFACE, 'Shuffle', False)
         self.assertFalse(self.backend.playback.shuffle.get())
 
+    def test_get_volume_should_return_volume_between_zero_and_one(self):
+        self.mixer.volume = 0
+        result = self.mpris.Get(mpris.PLAYER_IFACE, 'Volume')
+        self.assertEquals(result, 0)
+
+        self.mixer.volume = 50
+        result = self.mpris.Get(mpris.PLAYER_IFACE, 'Volume')
+        self.assertEquals(result, 0.5)
+
+        self.mixer.volume = 100
+        result = self.mpris.Get(mpris.PLAYER_IFACE, 'Volume')
+        self.assertEquals(result, 1)
+
+    def test_set_volume_to_one_should_set_mixer_volume_to_100(self):
+        self.mpris.Set(mpris.PLAYER_IFACE, 'Volume', 1.0)
+        self.assertEquals(self.mixer.volume.get(), 100)
+
+    def test_set_volume_to_anything_above_one_should_set_mixer_volume_to_100(self):
+        self.mpris.Set(mpris.PLAYER_IFACE, 'Volume', 2.0)
+        self.assertEquals(self.mixer.volume.get(), 100)
+
+    def test_set_volume_to_anything_not_a_number_does_not_change_volume(self):
+        self.mixer.volume = 10
+        self.mpris.Set(mpris.PLAYER_IFACE, 'Volume', None)
+        self.assertEquals(self.mixer.volume.get(), 10)
+
     def test_get_minimum_rate_is_one_or_less(self):
         result = self.mpris.Get(mpris.PLAYER_IFACE, 'MinimumRate')
         self.assert_(result <= 1.0)