Add full support for org.mpris.MediaPlayer2 interface (not including TrackList and Player)

mopidy/frontends/mpris.py

@@ -1,21 +1,22 @@
+import gobject
+gobject.threads_init()
+
 import logging
 import multiprocessing
-import socket
-import time
 
 try:
     import dbus
+    import dbus.service
+    from dbus.mainloop.glib import DBusGMainLoop
 except ImportError as import_error:
     from mopidy import OptionalDependencyError
     raise OptionalDependencyError(import_error)
 
-from mopidy import get_version, settings, SettingsError
 from mopidy.frontends.base import BaseFrontend
 from mopidy.utils.process import BaseThread
 
 logger = logging.getLogger('mopidy.frontends.mpris')
 
-BUS_NAME = u'org.mpris.MediaPlayer2.mopidy'
 
 class MprisFrontend(BaseFrontend):
     """
@@ -50,7 +51,12 @@ class MprisFrontendThread(BaseThread):
         super(MprisFrontendThread, self).__init__(core_queue)
         self.name = u'MprisFrontendThread'
         self.connection = connection
-        self.bus = None
+        self.dbus_objects = []
+
+    def destroy(self):
+        for dbus_object in self.dbus_objects:
+            dbus_object.remove_from_connection()
+        self.dbus_objects = []
 
     def run_inside_try(self):
         self.setup()
@@ -60,8 +66,111 @@ class MprisFrontendThread(BaseThread):
             self.process_message(message)
 
     def setup(self):
-        self.bus = dbus.SystemBus()
-        logger.info(u'Connected to D-Bus/MPRIS')
+        self.dbus_objects.append(MprisObject(self.core_queue))
+
+        # TODO Move to another thread if we need to process messages
+        logger.debug(u'Starting GLib main loop')
+        loop = gobject.MainLoop()
+        loop.run()
 
     def process_message(self, message):
         pass # Ignore commands for other frontends
+
+
+class MprisObject(dbus.service.Object):
+    """Implements http://www.mpris.org/2.0/spec/"""
+
+    bus_name = 'org.mpris.MediaPlayer2.mopidy'
+    object_path = '/org/mpris/MediaPlayer2'
+    property_interface = 'org.freedesktop.DBus.Properties'
+    root_interface = 'org.mpris.MediaPlayer2'
+    player_interface = 'org.mpris.MediaPlayer2.Player'
+    properties = {
+        root_interface: {
+            'CanQuit': (True, None),
+            'CanRaise': (False, None),
+            # TODO Add track list support
+            'HasTrackList': (False, None),
+            'Identity': ('Mopidy', None),
+            # TODO Return URI schemes supported by backend configuration
+            'SupportedUriSchemes': (dbus.Array(signature='s'), None),
+            # TODO Return MIME types supported by local backend if active
+            'SupportedMimeTypes': (dbus.Array(signature='s'), None),
+        },
+        player_interface: {
+            # TODO
+        },
+    }
+
+    def __init__(self, core_queue):
+        self.core_queue = core_queue
+        logger.debug(u'Prepare the D-Bus main loop before connecting')
+        DBusGMainLoop(set_as_default=True)
+        logger.info(u'Connecting to D-Bus')
+        bus = dbus.SessionBus()
+        logger.debug(u'Connecting to D-Bus: claiming service name')
+        # FIXME We segfault at the next line 80% of the time
+        bus_name = dbus.service.BusName(self.bus_name, bus)
+        logger.debug(u'Connecting to D-Bus: registering service object')
+        super(MprisObject, self).__init__(object_path=self.object_path,
+            bus_name=bus_name)
+        logger.debug(u'Connecting to D-Bus: done')
+
+
+    ### Property interface
+
+    @dbus.service.method(dbus_interface=property_interface,
+        in_signature='ss', out_signature='v')
+    def Get(self, interface, prop):
+        getter, setter = self.properties[interface][prop]
+        return getter() if callable(getter) else getter
+
+    @dbus.service.method(dbus_interface=property_interface,
+        in_signature='s', out_signature='a{sv}')
+    def GetAll(self, interface):
+        """
+        To test, start Mopidy and then run the following in a Python shell::
+
+            import dbus
+            bus = dbus.SessionBus()
+            player = bus.get_object('org.mpris.MediaPlayer2.mopidy',
+                '/org/mpris/MediaPlayer2')
+            props = player.GetAll('org.mpris.MediaPlayer2',
+                dbus_interface='org.freedesktop.DBus.Properties')
+        """
+        getters = {}
+        for key, (getter, setter) in self.properties[interface].iteritems():
+            getters[key] = getter() if callable(getter) else getter
+        return getters
+
+    @dbus.service.method(dbus_interface=property_interface,
+        in_signature='ssv', out_signature='')
+    def Set(self, interface, prop, value):
+        getter, setter = self.properties[interface][prop]
+        if setter is not None:
+            setter(value)
+
+
+    ### Root interface
+
+    @dbus.service.method(dbus_interface=root_interface)
+    def Raise(self):
+        pass # We do not have a GUI
+
+    @dbus.service.method(dbus_interface=root_interface)
+    def Quit(self):
+        """
+        To test, start Mopidy and then run the following in a Python shell::
+
+            import dbus
+            bus = dbus.SessionBus()
+            player = bus.get_object('org.mpris.MediaPlayer2.mopidy',
+                '/org/mpris/MediaPlayer2')
+            player.Quit(dbus_interface='org.mpris.MediaPlayer2')
+        """
+        self.core_queue.put({'to': 'core', 'command': 'exit'})
+
+
+    ### Player interface
+
+    # TODO