Merge pull request #377 from jodal/feature/load-extensions

Load backends and frontends from extensions

mopidy/__main__.py

@@ -9,6 +9,7 @@ import sys
 import gobject
 gobject.threads_init()
 
+import pkg_resources
 import pykka.debug
 
 
@@ -54,10 +55,11 @@ def main():
         log.setup_logging(options.verbosity_level, options.save_debug_log)
         check_old_folders()
         setup_settings(options.interactive)
+        extensions = load_extensions()
         audio = setup_audio()
-        backends = setup_backends(audio)
+        backends = setup_backends(extensions, audio)
         core = setup_core(audio, backends)
-        setup_frontends(core)
+        setup_frontends(extensions, core)
         loop.run()
     except exceptions.SettingsError as ex:
         logger.error(ex.message)
@@ -67,9 +69,9 @@ def main():
         logger.exception(ex)
     finally:
         loop.quit()
-        stop_frontends()
+        stop_frontends(extensions)
         stop_core()
-        stop_backends()
+        stop_backends(extensions)
         stop_audio()
         process.stop_remaining_actors()
 
@@ -138,51 +140,86 @@ def setup_settings(interactive):
         sys.exit(1)
 
 
+def load_extensions():
+    extensions = []
+    for entry_point in pkg_resources.iter_entry_points('mopidy.extension'):
+        logger.debug('Loading extension %s', entry_point.name)
+
+        try:
+            extension_class = entry_point.load()
+        except pkg_resources.DistributionNotFound as ex:
+            logger.info(
+                'Disabled extension %s: Dependency %s not found',
+                entry_point.name, ex)
+            continue
+
+        extension = extension_class()
+
+        # TODO Validate configuration, filter out disabled extensions
+
+        try:
+            extension.validate_environment()
+        except exceptions.ExtensionError as ex:
+            logger.info(
+                'Disabled extension: %s (%s)', extension.name, ex.message)
+            continue
+
+        logger.info(
+            'Loaded extension %s: %s %s',
+            entry_point.name, extension.name, extension.version)
+        extensions.append(extension)
+    return extensions
+
+
 def setup_audio():
+    logger.info('Starting Mopidy audio')
     return Audio.start().proxy()
 
 
 def stop_audio():
+    logger.info('Stopping Mopidy audio')
     process.stop_actors_by_class(Audio)
 
 
-def setup_backends(audio):
+def setup_backends(extensions, audio):
+    logger.info('Starting Mopidy backends')
     backends = []
-    for backend_class_name in settings.BACKENDS:
-        backend_class = importing.get_class(backend_class_name)
-        backend = backend_class.start(audio=audio).proxy()
-        backends.append(backend)
+    for extension in extensions:
+        for backend_class in extension.get_backend_classes():
+            backend = backend_class.start(audio=audio).proxy()
+            backends.append(backend)
     return backends
 
 
-def stop_backends():
-    for backend_class_name in settings.BACKENDS:
-        process.stop_actors_by_class(importing.get_class(backend_class_name))
+def stop_backends(extensions):
+    logger.info('Stopping Mopidy backends')
+    for extension in extensions:
+        for backend_class in extension.get_backend_classes():
+            process.stop_actors_by_class(backend_class)
 
 
 def setup_core(audio, backends):
+    logger.info('Starting Mopidy core')
     return Core.start(audio=audio, backends=backends).proxy()
 
 
 def stop_core():
+    logger.info('Stopping Mopidy core')
     process.stop_actors_by_class(Core)
 
 
-def setup_frontends(core):
-    for frontend_class_name in settings.FRONTENDS:
-        try:
-            importing.get_class(frontend_class_name).start(core=core)
-        except exceptions.OptionalDependencyError as ex:
-            logger.info('Disabled: %s (%s)', frontend_class_name, ex)
+def setup_frontends(extensions, core):
+    logger.info('Starting Mopidy frontends')
+    for extension in extensions:
+        for frontend_class in extension.get_frontend_classes():
+            frontend_class.start(core=core)
 
 
-def stop_frontends():
-    for frontend_class_name in settings.FRONTENDS:
-        try:
-            frontend_class = importing.get_class(frontend_class_name)
+def stop_frontends(extensions):
+    logger.info('Stopping Mopidy frontends')
+    for extension in extensions:
+        for frontend_class in extension.get_frontend_classes():
             process.stop_actors_by_class(frontend_class)
-        except exceptions.OptionalDependencyError:
-            pass
 
 
 if __name__ == '__main__':

mopidy/backends/local/__init__.py

@@ -27,10 +27,6 @@ https://github.com/mopidy/mopidy/issues?labels=Local+backend
 """
 
 
-# TODO Move import into method when BACKENDS setting is removed
-from .actor import LocalBackend
-
-
 class Extension(ext.Extension):
 
     name = 'Mopidy-Local'
@@ -46,4 +42,5 @@ class Extension(ext.Extension):
         pass
 
     def get_backend_classes(self):
+        from .actor import LocalBackend
         return [LocalBackend]

mopidy/backends/spotify/__init__.py

@@ -65,10 +65,6 @@ https://github.com/mopidy/mopidy/issues?labels=Spotify+backend
 """ % {'config': indent(config)}
 
 
-# TODO Move import into method when BACKENDS setting is removed
-from .actor import SpotifyBackend
-
-
 class Extension(ext.Extension):
 
     name = 'Mopidy-Spotify'
@@ -92,4 +88,5 @@ class Extension(ext.Extension):
             raise ExtensionError('pyspotify library not found', e)
 
     def get_backend_classes(self):
+        from .actor import SpotifyBackend
         return [SpotifyBackend]

mopidy/backends/stream/__init__.py

@@ -24,10 +24,6 @@ https://github.com/mopidy/mopidy/issues?labels=Stream+backend
 """
 
 
-# TODO Move import into method when BACKENDS setting is removed
-from .actor import StreamBackend
-
-
 class Extension(ext.Extension):
 
     name = 'Mopidy-Stream'
@@ -43,4 +39,5 @@ class Extension(ext.Extension):
         pass
 
     def get_backend_classes(self):
+        from .actor import StreamBackend
         return [StreamBackend]

mopidy/frontends/http/__init__.py

@@ -485,10 +485,6 @@ Example to get started with
 """
 
 
-# TODO Move import into method when FRONTENDS setting is removed
-from .actor import HttpFrontend
-
-
 class Extension(ext.Extension):
 
     name = 'Mopidy-HTTP'
@@ -512,4 +508,5 @@ class Extension(ext.Extension):
             raise ExtensionError('Library ws4py not found', e)
 
     def get_frontend_classes(self):
+        from .actor import HttpFrontend
         return [HttpFrontend]

mopidy/frontends/lastfm/__init__.py

@@ -30,10 +30,6 @@ the Last.fm frontend.
 """
 
 
-# TODO Move import into method when FRONTENDS setting is removed
-from .actor import LastfmFrontend
-
-
 class Extension(ext.Extension):
 
     name = 'Mopidy-Lastfm'
@@ -52,4 +48,5 @@ class Extension(ext.Extension):
             raise ExtensionError('pylast library not found', e)
 
     def get_frontend_classes(self):
+        from .actor import LastfmFrontend
         return [LastfmFrontend]

mopidy/frontends/mpd/__init__.py

@@ -51,10 +51,6 @@ near future:
 """
 
 
-# TODO Move import into method when FRONTENDS setting is removed
-from .actor import MpdFrontend
-
-
 class Extension(ext.Extension):
 
     name = 'Mopidy-MPD'
@@ -70,4 +66,5 @@ class Extension(ext.Extension):
         pass
 
     def get_frontend_classes(self):
+        from .actor import MpdFrontend
         return [MpdFrontend]

mopidy/frontends/mpris/__init__.py

@@ -58,10 +58,6 @@ Now you can control Mopidy through the player object. Examples:
 """
 
 
-# TODO Move import into method when FRONTENDS setting is removed
-from .actor import MprisFrontend
-
-
 class Extension(ext.Extension):
 
     name = 'Mopidy-MPRIS'
@@ -80,4 +76,5 @@ class Extension(ext.Extension):
             raise ExtensionError('Library dbus not found', e)
 
     def get_frontend_classes(self):
+        from .actor import MprisFrontend
         return [MprisFrontend]

setup.py

@@ -45,12 +45,12 @@ setup(
             'mopidy-scan = mopidy.scanner:main',
         ],
         b'mopidy.extension': [
-            'http = mopidy.frontends.http:Extension',
-            'lastfm = mopidy.frontends.lastfm:Extension',
+            'http = mopidy.frontends.http:Extension [http]',
+            'lastfm = mopidy.frontends.lastfm:Extension [lastfm]',
             'local = mopidy.backends.local:Extension',
             'mpd = mopidy.frontends.mpd:Extension',
             'mpris = mopidy.frontends.mpris:Extension',
-            'spotify = mopidy.backends.spotify:Extension',
+            'spotify = mopidy.backends.spotify:Extension [spotify]',
             'stream = mopidy.backends.stream:Extension',
         ],
     },

tests/backends/local/events_test.py

@@ -1,12 +1,12 @@
 from mopidy import settings
-from mopidy.backends.local import LocalBackend
+from mopidy.backends.local import actor
 
 from tests import unittest, path_to_data_dir
 from tests.backends.base import events
 
 
 class LocalBackendEventsTest(events.BackendEventsTest, unittest.TestCase):
-    backend_class = LocalBackend
+    backend_class = actor.LocalBackend
 
     def setUp(self):
         settings.LOCAL_TAG_CACHE_FILE = path_to_data_dir('empty_tag_cache')

tests/backends/local/library_test.py

@@ -1,7 +1,7 @@
 from __future__ import unicode_literals
 
 from mopidy import settings
-from mopidy.backends.local import LocalBackend
+from mopidy.backends.local import actor
 
 from tests import unittest, path_to_data_dir
 from tests.backends.base.library import LibraryControllerTest
@@ -9,7 +9,7 @@ from tests.backends.base.library import LibraryControllerTest
 
 class LocalLibraryControllerTest(LibraryControllerTest, unittest.TestCase):
 
-    backend_class = LocalBackend
+    backend_class = actor.LocalBackend
 
     def setUp(self):
         settings.LOCAL_TAG_CACHE_FILE = path_to_data_dir('library_tag_cache')

tests/backends/local/playback_test.py

@@ -1,7 +1,7 @@
 from __future__ import unicode_literals
 
 from mopidy import settings
-from mopidy.backends.local import LocalBackend
+from mopidy.backends.local import actor
 from mopidy.core import PlaybackState
 from mopidy.models import Track
 from mopidy.utils.path import path_to_uri
@@ -12,7 +12,7 @@ from tests.backends.local import generate_song
 
 
 class LocalPlaybackControllerTest(PlaybackControllerTest, unittest.TestCase):
-    backend_class = LocalBackend
+    backend_class = actor.LocalBackend
     tracks = [
         Track(uri=generate_song(i), length=4464) for i in range(1, 4)]
 

tests/backends/local/playlists_test.py

@@ -3,7 +3,7 @@ from __future__ import unicode_literals
 import os
 
 from mopidy import settings
-from mopidy.backends.local import LocalBackend
+from mopidy.backends.local import actor
 from mopidy.models import Track
 from mopidy.utils.path import path_to_uri
 
@@ -16,7 +16,7 @@ from tests.backends.local import generate_song
 class LocalPlaylistsControllerTest(
         PlaylistsControllerTest, unittest.TestCase):
 
-    backend_class = LocalBackend
+    backend_class = actor.LocalBackend
 
     def setUp(self):
         settings.LOCAL_TAG_CACHE_FILE = path_to_data_dir('empty_tag_cache')

tests/backends/local/tracklist_test.py

@@ -1,7 +1,7 @@
 from __future__ import unicode_literals
 
 from mopidy import settings
-from mopidy.backends.local import LocalBackend
+from mopidy.backends.local import actor
 from mopidy.models import Track
 
 from tests import unittest, path_to_data_dir
@@ -10,7 +10,7 @@ from tests.backends.local import generate_song
 
 
 class LocalTracklistControllerTest(TracklistControllerTest, unittest.TestCase):
-    backend_class = LocalBackend
+    backend_class = actor.LocalBackend
     tracks = [
         Track(uri=generate_song(i), length=4464) for i in range(1, 4)]
 

tests/frontends/http/events_test.py

@@ -12,7 +12,7 @@ import mock
 
 from mopidy.exceptions import OptionalDependencyError
 try:
-    from mopidy.frontends.http import HttpFrontend
+    from mopidy.frontends.http import actor
 except OptionalDependencyError:
     pass
 
@@ -24,7 +24,7 @@ from tests import unittest
 @mock.patch('cherrypy.engine.publish')
 class HttpEventsTest(unittest.TestCase):
     def setUp(self):
-        self.http = HttpFrontend(core=mock.Mock())
+        self.http = actor.HttpFrontend(core=mock.Mock())
 
     def test_track_playback_paused_is_broadcasted(self, publish):
         publish.reset_mock()

tests/frontends/mpris/events_test.py

@@ -8,7 +8,7 @@ from mopidy.exceptions import OptionalDependencyError
 from mopidy.models import Playlist, TlTrack
 
 try:
-    from mopidy.frontends.mpris import MprisFrontend, objects
+    from mopidy.frontends.mpris import actor, objects
 except OptionalDependencyError:
     pass
 
@@ -19,7 +19,7 @@ from tests import unittest
 class BackendEventsTest(unittest.TestCase):
     def setUp(self):
         # As a plain class, not an actor:
-        self.mpris_frontend = MprisFrontend(core=None)
+        self.mpris_frontend = actor.MprisFrontend(core=None)
         self.mpris_object = mock.Mock(spec=objects.MprisObject)
         self.mpris_frontend.mpris_object = self.mpris_object