[WIP] music.mopidy refactor, initial backend rewrite.

docs/source/backends.rst

@@ -8,7 +8,6 @@ Backends
 
     platypush/backend/http.rst
     platypush/backend/midi.rst
-    platypush/backend/music.mopidy.rst
     platypush/backend/music.spotify.rst
     platypush/backend/nodered.rst
     platypush/backend/redis.rst

docs/source/platypush/backend/music.mopidy.rst

@@ -1,6 +0,0 @@
-``music.mopidy``
-==================================
-
-.. automodule:: platypush.backend.music.mopidy
-	:members:
-

docs/source/platypush/plugins/music.mopidy.rst

@@ -0,0 +1,5 @@
+``music.mopidy``
+================
+
+.. automodule:: platypush.plugins.music.mopidy
+    :members:

docs/source/plugins.rst

@@ -84,6 +84,7 @@ Plugins
     platypush/plugins/ml.cv.rst
     platypush/plugins/mobile.join.rst
     platypush/plugins/mqtt.rst
+    platypush/plugins/music.mopidy.rst
     platypush/plugins/music.mpd.rst
     platypush/plugins/music.snapcast.rst
     platypush/plugins/music.spotify.rst

platypush/backend/music/mopidy/__init__.py

@@ -1,324 +0,0 @@
-import json
-import re
-import threading
-
-import websocket
-
-from platypush.backend import Backend
-from platypush.message.event.music import (
-    MusicPlayEvent,
-    MusicPauseEvent,
-    MusicStopEvent,
-    NewPlayingTrackEvent,
-    PlaylistChangeEvent,
-    VolumeChangeEvent,
-    PlaybackConsumeModeChangeEvent,
-    PlaybackSingleModeChangeEvent,
-    PlaybackRepeatModeChangeEvent,
-    PlaybackRandomModeChangeEvent,
-    MuteChangeEvent,
-    SeekChangeEvent,
-)
-
-
-# noinspection PyUnusedLocal
-class MusicMopidyBackend(Backend):
-    """
-    This backend listens for events on a Mopidy music server streaming port.
-    Since this backend leverages the Mopidy websocket interface it is only
-    compatible with Mopidy and not with other MPD servers. Please use the
-    :class:`platypush.backend.music.mpd.MusicMpdBackend` for a similar polling
-    solution if you're not running Mopidy or your instance has the websocket
-    interface or web port disabled.
-
-    Requires:
-
-        * A Mopidy instance running with the HTTP service enabled.
-
-    """
-
-    def __init__(self, host='localhost', port=6680, **kwargs):
-        super().__init__(**kwargs)
-
-        self.host = host
-        self.port = int(port)
-        self.url = 'ws://{}:{}/mopidy/ws'.format(host, port)
-        self._msg_id = 0
-        self._ws = None
-        self._latest_status = {}
-        self._reconnect_thread = None
-        self._connected_event = threading.Event()
-
-        try:
-            self._latest_status = self._get_tracklist_status()
-        except Exception as e:
-            self.logger.warning('Unable to get mopidy status: {}'.format(str(e)))
-
-    @staticmethod
-    def _parse_track(track, pos=None):
-        if not track:
-            return {}
-
-        conv_track = track.get('track', {}).copy()
-        conv_track['id'] = track.get('tlid')
-        conv_track['file'] = conv_track['uri']
-        del conv_track['uri']
-
-        if 'artists' in conv_track:
-            conv_track['artist'] = conv_track['artists'][0].get('name')
-            del conv_track['artists']
-
-        if 'name' in conv_track:
-            conv_track['title'] = conv_track['name']
-            del conv_track['name']
-
-        if 'album' in conv_track:
-            conv_track['album'] = conv_track['album']['name']
-
-        if 'length' in conv_track:
-            conv_track['time'] = (
-                conv_track['length'] / 1000
-                if conv_track['length']
-                else conv_track['length']
-            )
-            del conv_track['length']
-
-        if pos is not None:
-            conv_track['pos'] = pos
-
-        if '__model__' in conv_track:
-            del conv_track['__model__']
-
-        return conv_track
-
-    def _communicate(self, msg):
-        if isinstance(msg, str):
-            msg = json.loads(msg)
-
-        self._msg_id += 1
-        msg['jsonrpc'] = '2.0'
-        msg['id'] = self._msg_id
-        msg = json.dumps(msg)
-
-        ws = websocket.create_connection(self.url)
-        ws.send(msg)
-        response = json.loads(ws.recv()).get('result')
-        ws.close()
-        return response
-
-    def _get_tracklist_status(self):
-        return {
-            'repeat': self._communicate({'method': 'core.tracklist.get_repeat'}),
-            'random': self._communicate({'method': 'core.tracklist.get_random'}),
-            'single': self._communicate({'method': 'core.tracklist.get_single'}),
-            'consume': self._communicate({'method': 'core.tracklist.get_consume'}),
-        }
-
-    def _on_msg(self):
-        def hndl(*args):
-            msg = args[1] if len(args) > 1 else args[0]
-            msg = json.loads(msg)
-            event = msg.get('event')
-            if not event:
-                return
-
-            status = {}
-            track = msg.get('tl_track', {})
-
-            if event == 'track_playback_paused':
-                status['state'] = 'pause'
-                track = self._parse_track(track)
-                if not track:
-                    return
-                self.bus.post(
-                    MusicPauseEvent(status=status, track=track, plugin_name='music.mpd')
-                )
-            elif event == 'track_playback_resumed':
-                status['state'] = 'play'
-                track = self._parse_track(track)
-                if not track:
-                    return
-                self.bus.post(
-                    MusicPlayEvent(status=status, track=track, plugin_name='music.mpd')
-                )
-            elif event == 'track_playback_ended' or (
-                event == 'playback_state_changed' and msg.get('new_state') == 'stopped'
-            ):
-                status['state'] = 'stop'
-                track = self._parse_track(track)
-                self.bus.post(
-                    MusicStopEvent(status=status, track=track, plugin_name='music.mpd')
-                )
-            elif event == 'track_playback_started':
-                track = self._parse_track(track)
-                if not track:
-                    return
-
-                status['state'] = 'play'
-                status['position'] = 0.0
-                status['time'] = track.get('time')
-                self.bus.post(
-                    NewPlayingTrackEvent(
-                        status=status, track=track, plugin_name='music.mpd'
-                    )
-                )
-            elif event == 'stream_title_changed':
-                m = re.match(r'^\s*(.+?)\s+-\s+(.*)\s*$', msg.get('title', ''))
-                if not m:
-                    return
-
-                track['artist'] = m.group(1)
-                track['title'] = m.group(2)
-                status['state'] = 'play'
-                status['position'] = 0.0
-                self.bus.post(
-                    NewPlayingTrackEvent(
-                        status=status, track=track, plugin_name='music.mpd'
-                    )
-                )
-            elif event == 'volume_changed':
-                status['volume'] = msg.get('volume')
-                self.bus.post(
-                    VolumeChangeEvent(
-                        volume=status['volume'],
-                        status=status,
-                        track=track,
-                        plugin_name='music.mpd',
-                    )
-                )
-            elif event == 'mute_changed':
-                status['mute'] = msg.get('mute')
-                self.bus.post(
-                    MuteChangeEvent(
-                        mute=status['mute'],
-                        status=status,
-                        track=track,
-                        plugin_name='music.mpd',
-                    )
-                )
-            elif event == 'seeked':
-                status['position'] = msg.get('time_position') / 1000
-                self.bus.post(
-                    SeekChangeEvent(
-                        position=status['position'],
-                        status=status,
-                        track=track,
-                        plugin_name='music.mpd',
-                    )
-                )
-            elif event == 'tracklist_changed':
-                tracklist = [
-                    self._parse_track(t, pos=i)
-                    for i, t in enumerate(
-                        self._communicate({'method': 'core.tracklist.get_tl_tracks'})
-                    )
-                ]
-
-                self.bus.post(
-                    PlaylistChangeEvent(changes=tracklist, plugin_name='music.mpd')
-                )
-            elif event == 'options_changed':
-                new_status = self._get_tracklist_status()
-                if new_status['random'] != self._latest_status.get('random'):
-                    self.bus.post(
-                        PlaybackRandomModeChangeEvent(
-                            state=new_status['random'], plugin_name='music.mpd'
-                        )
-                    )
-                if new_status['repeat'] != self._latest_status['repeat']:
-                    self.bus.post(
-                        PlaybackRepeatModeChangeEvent(
-                            state=new_status['repeat'], plugin_name='music.mpd'
-                        )
-                    )
-                if new_status['single'] != self._latest_status['single']:
-                    self.bus.post(
-                        PlaybackSingleModeChangeEvent(
-                            state=new_status['single'], plugin_name='music.mpd'
-                        )
-                    )
-                if new_status['consume'] != self._latest_status['consume']:
-                    self.bus.post(
-                        PlaybackConsumeModeChangeEvent(
-                            state=new_status['consume'], plugin_name='music.mpd'
-                        )
-                    )
-
-                self._latest_status = new_status
-
-        return hndl
-
-    def _retry_connect(self):
-        def reconnect():
-            while not self.should_stop() and not self._connected_event.is_set():
-                try:
-                    self._connect()
-                except Exception as e:
-                    self.logger.warning('Error on websocket reconnection: %s', e)
-
-                self._connected_event.wait(timeout=10)
-
-            self._reconnect_thread = None
-
-        if not self._reconnect_thread or not self._reconnect_thread.is_alive():
-            self._reconnect_thread = threading.Thread(target=reconnect)
-            self._reconnect_thread.start()
-
-    def _on_error(self):
-        def hndl(*args):
-            error = args[1] if len(args) > 1 else args[0]
-            ws = args[0] if len(args) > 1 else None
-            self.logger.warning('Mopidy websocket error: {}'.format(error))
-            if ws:
-                ws.close()
-
-        return hndl
-
-    def _on_close(self):
-        def hndl(*_):
-            self._connected_event.clear()
-            self._ws = None
-            self.logger.warning('Mopidy websocket connection closed')
-
-            if not self.should_stop():
-                self._retry_connect()
-
-        return hndl
-
-    def _on_open(self):
-        def hndl(*_):
-            self._connected_event.set()
-            self.logger.info('Mopidy websocket connected')
-
-        return hndl
-
-    def _connect(self):
-        if not self._ws:
-            self._ws = websocket.WebSocketApp(
-                self.url,
-                on_open=self._on_open(),
-                on_message=self._on_msg(),
-                on_error=self._on_error(),
-                on_close=self._on_close(),
-            )
-
-            self._ws.run_forever()
-
-    def run(self):
-        super().run()
-        self.logger.info(
-            'Started tracking Mopidy events backend on {}:{}'.format(
-                self.host, self.port
-            )
-        )
-        self._connect()
-
-    def on_stop(self):
-        self.logger.info('Received STOP event on the Mopidy backend')
-        if self._ws:
-            self._ws.close()
-
-        self.logger.info('Mopidy backend terminated')
-
-
-# vim:sw=4:ts=4:et:

platypush/plugins/music/__init__.py

@@ -1,5 +1,5 @@
 from abc import ABC, abstractmethod
-from typing import Optional
+from typing import Dict, Iterable, Optional
 
 from platypush.plugins import Plugin, action
 
@@ -107,5 +107,18 @@ class MusicPlugin(Plugin, ABC):
     def search(self, query, **kwargs):
         raise NotImplementedError()
 
+    @action
+    def get_images(self, resources: Iterable[str], **__) -> Dict[str, Optional[str]]:
+        """
+        Get the images for a list of URIs.
+
+        .. note:: This is an optional action, and it may not be implemented by all plugins.
+                  If the plugin doesn't implement this action, it will return an empty dictionary.
+
+        :param uris: List of URIs.
+        :return: Dictionary in the form ``{uri: image_url}``.
+        """
+        return {}
+
 
 # vim:sw=4:ts=4:et:

platypush/plugins/music/mopidy/_client.py

@@ -0,0 +1,486 @@
+import json
+import logging
+import re
+import time
+from dataclasses import asdict
+from queue import Empty
+from threading import Event, RLock, Thread
+from typing import Dict, Generator, List, Optional, Type
+
+import websocket
+
+from platypush.context import get_bus
+from platypush.message.event.music import (
+    MusicEvent,
+    MusicPauseEvent,
+    MusicPlayEvent,
+    MusicStopEvent,
+    MuteChangeEvent,
+    NewPlayingTrackEvent,
+    PlaybackConsumeModeChangeEvent,
+    PlaybackRandomModeChangeEvent,
+    PlaybackRepeatModeChangeEvent,
+    PlaybackSingleModeChangeEvent,
+    PlaylistChangeEvent,
+    SeekChangeEvent,
+    VolumeChangeEvent,
+)
+from platypush.plugins.media import PlayerState
+
+from ._common import DEFAULT_TIMEOUT
+from ._conf import MopidyConfig
+from ._status import MopidyStatus
+from ._sync import PlaylistSync
+from ._task import MopidyTask
+from ._track import MopidyTrack
+
+
+class MopidyClient(Thread):
+    """
+    Thread that listens for Mopidy events and posts them to the bus.
+    """
+
+    def __init__(
+        self,
+        config: MopidyConfig,
+        status: MopidyStatus,
+        stop_event: Event,
+        playlist_sync: PlaylistSync,
+        tasks: Dict[int, MopidyTask],
+        **_,
+    ):
+        super().__init__(name='platypush:mopidy:listener')
+
+        self.logger = logging.getLogger('platypush:mopidy:listener')
+        self.config = config
+        self._status = status
+        self._stop_event = stop_event
+        self._playlist_sync = playlist_sync
+        self._tasks = tasks
+        self._refresh_in_progress = Event()
+        self._refresh_lock = RLock()
+        self._req_lock = RLock()
+        self._close_lock = RLock()
+        self._tracks: List[MopidyTrack] = []
+        self._msg_id = 0
+        self._ws = None
+        self.connected_event = Event()
+        self.closed_event = Event()
+
+    @property
+    def _bus(self):
+        return get_bus()
+
+    @property
+    def status(self):
+        return self._status
+
+    @property
+    def tracks(self):
+        return self._tracks
+
+    def should_stop(self):
+        return self._stop_event.is_set()
+
+    def wait_stop(self, timeout: Optional[float] = None):
+        self._stop_event.wait(timeout=timeout)
+
+    def make_task(self, method: str, **args: dict) -> MopidyTask:
+        with self._req_lock:
+            self._msg_id += 1
+            task = MopidyTask(
+                id=self._msg_id,
+                method=method,
+                args=args or {},
+            )
+
+        self._tasks[task.id] = task
+        return task
+
+    def send(self, *tasks: MopidyTask):
+        """
+        Send a list of tasks to the Mopidy server.
+        """
+        assert self._ws, 'Websocket not connected'
+
+        for task in tasks:
+            with self._req_lock:
+                task.send(self._ws)
+
+    def gather(
+        self,
+        *tasks: MopidyTask,
+        timeout: Optional[float] = DEFAULT_TIMEOUT,
+    ) -> Generator:
+        t_start = time.time()
+
+        for task in tasks:
+            remaining_timeout = (
+                max(0, timeout - (time.time() - t_start)) if timeout else None
+            )
+
+            if not self._tasks.get(task.id):
+                yield None
+
+            try:
+                ret = self._tasks[task.id].get_response(timeout=remaining_timeout)
+                assert not isinstance(ret, Exception), ret
+                self.logger.debug('Got response for %s: %s', task, ret)
+                yield ret
+            except Empty as e:
+                t = self._tasks.get(task.id)
+                err = 'Mopidy request timeout'
+                if t:
+                    err += f' - method: {t.method} args: {t.args}'
+
+                raise TimeoutError(err) from e
+            finally:
+                self._tasks.pop(task.id, None)
+
+    def exec(self, *msgs: dict, timeout: Optional[float] = DEFAULT_TIMEOUT) -> list:
+        tasks = [self.make_task(**msg) for msg in msgs]
+        for task in tasks:
+            self.send(task)
+
+        return list(self.gather(*tasks, timeout=timeout))
+
+    def refresh_status(  # pylint: disable=too-many-branches
+        self, timeout: Optional[float] = DEFAULT_TIMEOUT, with_tracks: bool = False
+    ):
+        if self._refresh_in_progress.is_set():
+            return
+
+        events = []
+
+        try:
+            with self._refresh_lock:
+                self._refresh_in_progress.set()
+                # Refresh the tracklist attributes
+                opts = ('repeat', 'random', 'single', 'consume')
+                ret = self.exec(
+                    *[
+                        *[{'method': f'core.tracklist.get_{opt}'} for opt in opts],
+                        {'method': 'core.playback.get_current_tl_track'},
+                        {'method': 'core.playback.get_state'},
+                        {'method': 'core.mixer.get_volume'},
+                        {'method': 'core.playback.get_time_position'},
+                        *(
+                            [{'method': 'core.tracklist.get_tl_tracks'}]
+                            if with_tracks
+                            else []
+                        ),
+                    ],
+                    timeout=timeout,
+                )
+
+                for i, opt in enumerate(opts):
+                    new_value = ret[i]
+                    if opt == 'random' and self._status.random != new_value:
+                        events.append(
+                            (PlaybackRandomModeChangeEvent, {'state': new_value})
+                        )
+                    if opt == 'repeat' and self._status.repeat != new_value:
+                        events.append(
+                            (PlaybackRepeatModeChangeEvent, {'state': new_value})
+                        )
+                    if opt == 'single' and self._status.single != new_value:
+                        events.append(
+                            (PlaybackSingleModeChangeEvent, {'state': new_value})
+                        )
+                    if opt == 'consume' and self._status.consume != new_value:
+                        events.append(
+                            (PlaybackConsumeModeChangeEvent, {'state': new_value})
+                        )
+
+                    setattr(self._status, opt, new_value)
+
+                # Get remaining info
+                track = MopidyTrack.parse(ret[4])
+                state, volume, t = ret[5:8]
+
+                if track:
+                    idx = self.exec(
+                        {
+                            'method': 'core.tracklist.index',
+                            'tlid': track.track_id,
+                        },
+                        timeout=timeout,
+                    )[0]
+
+                    self._status.track = track
+                    self._status.duration = track.time
+                    if idx is not None:
+                        self._status.playing_pos = self._status.track.playlist_pos = idx
+
+                    if track != self._status.track and state != 'stopped':
+                        events.append((NewPlayingTrackEvent, {}))
+
+                if state != self._status.state:
+                    if state == 'paused':
+                        self._status.state = PlayerState.PAUSE
+                        events.append((MusicPauseEvent, {}))
+                    elif state == 'playing':
+                        self._status.state = PlayerState.PLAY
+                        events.append((MusicPlayEvent, {}))
+                    elif state == 'stopped':
+                        self._status.state = PlayerState.STOP
+                        events.append((MusicStopEvent, {}))
+
+                if volume != self._status.volume:
+                    self._status.volume = volume
+                    events.append((VolumeChangeEvent, {'volume': volume}))
+
+                if t != self._status.time:
+                    self._status.time = t / 1000
+                    events.append((SeekChangeEvent, {'position': self._status.time}))
+
+                if with_tracks:
+                    self._tracks = [  # type: ignore
+                        MopidyTrack.parse({**t, 'playlist_pos': i})
+                        for i, t in enumerate(ret[8])
+                    ]
+
+            for evt in events:
+                self._post_event(evt[0], **evt[1])
+        finally:
+            self._refresh_in_progress.clear()
+
+    def _refresh_status(
+        self, timeout: Optional[float] = DEFAULT_TIMEOUT, with_tracks: bool = False
+    ):
+        """
+        Refresh the status from the Mopidy server.
+
+        It runs in a separate thread because the status refresh logic runs in
+        synchronous mode, and it would block the main thread preventing the
+        listener from receiving new messages.
+
+        Also, an event+reenrant lock mechanism is used to ensure that only one
+        refresh task is running at a time.
+        """
+        if self._refresh_in_progress.is_set():
+            return
+
+        with self._refresh_lock:
+            Thread(
+                target=self.refresh_status,
+                kwargs={'timeout': timeout, 'with_tracks': with_tracks},
+                daemon=True,
+            ).start()
+
+    def _post_event(self, evt_cls: Type[MusicEvent], **kwargs):
+        self._bus.post(
+            evt_cls(
+                status=asdict(self._status),
+                track=asdict(self._status.track) if self._status.track else None,
+                plugin_name='music.mopidy',
+                **kwargs,
+            )
+        )
+
+    def _handle_error(self, msg: dict):
+        msg_id = msg.get('id')
+        err = msg.get('error')
+        if not err:
+            return
+
+        err_data = err.get('data', {})
+        tb = err_data.get('traceback')
+        self.logger.warning(
+            'Mopidy error: %s: %s: %s',
+            err.get('message'),
+            err_data.get('type'),
+            err_data.get('message'),
+        )
+        if tb:
+            self.logger.warning(tb)
+
+        if msg_id:
+            task = self._tasks.get(msg_id)
+            if task:
+                task.put_response(
+                    RuntimeError(err.get('message') + ': ' + err_data.get('message'))
+                )
+
+    def on_pause(self, *_, **__):
+        self._status.state = PlayerState.PAUSE
+        self._post_event(MusicPauseEvent)
+
+    def on_resume(self, *_, **__):
+        self._status.state = PlayerState.PLAY
+        self._post_event(MusicPlayEvent)
+
+    def on_start(self, *_, **__):
+        self._refresh_status()
+
+    def on_end(self, *_, **__):
+        self._refresh_status()
+
+    def on_state_change(self, msg: dict, *_, **__):
+        state = msg.get('new_state')
+        if state == PlayerState.PLAY:
+            self._status.state = PlayerState.PLAY
+            self._post_event(MusicPlayEvent)
+        elif state == PlayerState.PAUSE:
+            self._status.state = PlayerState.PAUSE
+            self._post_event(MusicPauseEvent)
+        elif state == PlayerState.STOP:
+            self._status.state = PlayerState.STOP
+            self._post_event(MusicStopEvent)
+
+    def on_title_change(self, msg: dict, *_, track: MopidyTrack, **__):
+        title = msg.get('title', '')
+        m = re.match(r'^\s*(.+?)\s+-\s+(.*)\s*$', title)
+        if not m:
+            return
+
+        track.artist = m.group(1)
+        track.title = m.group(2)
+        self._post_event(NewPlayingTrackEvent)
+
+    def on_volume_change(self, msg: dict, *_, **__):
+        volume = msg.get('volume')
+        if volume is None:
+            return
+
+        self._status.volume = volume
+        self._post_event(VolumeChangeEvent, volume=volume)
+
+    def on_mute_change(self, msg: dict, *_, **__):
+        mute = msg.get('mute')
+        if mute is None:
+            return
+
+        self._status.mute = mute
+        self._post_event(MuteChangeEvent, mute=mute)
+
+    def on_seek(self, msg: dict, *_, **__):
+        position = msg.get('time_position')
+        if position is None:
+            return
+
+        self._status.time = position / 1000
+        self._post_event(SeekChangeEvent, position=self._status.time)
+
+    def on_tracklist_change(self, *_, **__):
+        should_proceed = self._playlist_sync.wait_for_loading(timeout=2)
+        if not should_proceed:
+            return
+
+        self.logger.debug('Tracklist changed, refreshing changes')
+        self._refresh_status(with_tracks=True)
+        self._post_event(PlaylistChangeEvent)
+
+    def on_options_change(self, *_, **__):
+        self._refresh_status()
+
+    def _on_msg(self, *args):
+        msg = args[1] if len(args) > 1 else args[0]
+        msg = json.loads(msg)
+        msg_id = msg.get('id')
+        event = msg.get('event')
+        track: Optional[MopidyTrack] = None
+        self.logger.debug('Received Mopidy message: %s', msg)
+
+        if msg.get('error'):
+            self._handle_error(msg)
+            return
+
+        if msg_id:
+            task = self._tasks.get(msg_id)
+            if task:
+                task.put_response(msg)
+                return
+
+        if not event:
+            return
+
+        if msg.get('tl_track'):
+            track = self._status.track = MopidyTrack.parse(msg['tl_track'])
+
+        hndl = self._msg_handlers.get(event)
+        if not hndl:
+            return
+
+        hndl(self, msg, track=track)
+
+    def _on_error(self, *args):
+        error = args[1] if len(args) > 1 else args[0]
+        ws = args[0] if len(args) > 1 else None
+        self.logger.warning('Mopidy websocket error: %s', error)
+        if ws:
+            ws.close()
+
+    def _on_close(self, *_):
+        self.connected_event.clear()
+        self.closed_event.set()
+
+        if self._ws:
+            try:
+                self._ws.close()
+            except Exception as e:
+                self.logger.debug(e, exc_info=True)
+            finally:
+                self._ws = None
+
+        self.logger.warning('Mopidy websocket connection closed')
+
+    def _on_open(self, *_):
+        self.connected_event.set()
+        self.closed_event.clear()
+        self.logger.info('Mopidy websocket connected')
+        self._refresh_status(with_tracks=True)
+
+    def _connect(self):
+        if not self._ws:
+            self._ws = websocket.WebSocketApp(
+                self.config.url,
+                on_open=self._on_open,
+                on_message=self._on_msg,
+                on_error=self._on_error,
+                on_close=self._on_close,
+            )
+
+            self._ws.run_forever()
+
+    def run(self):
+        while not self.should_stop():
+            try:
+                self._connect()
+            except Exception as e:
+                self.logger.warning(
+                    'Error on websocket connection: %s', e, exc_info=True
+                )
+            finally:
+                self.connected_event.clear()
+                self.closed_event.set()
+                self.wait_stop(10)
+
+    def stop(self):
+        with self._close_lock:
+            if self._ws:
+                self._ws.close()
+                self._ws = None
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *_):
+        self.stop()
+
+    _msg_handlers = {
+        'track_playback_paused': on_pause,
+        'playback_state_changed': on_state_change,
+        'track_playback_resumed': on_resume,
+        'track_playback_ended': on_end,
+        'track_playback_started': on_start,
+        'stream_title_changed': on_title_change,
+        'volume_changed': on_volume_change,
+        'mute_changed': on_mute_change,
+        'seeked': on_seek,
+        'tracklist_changed': on_tracklist_change,
+        'options_changed': on_options_change,
+    }
+
+
+# vim:sw=4:ts=4:et:

platypush/plugins/music/mopidy/_common.py

@@ -0,0 +1,4 @@
+from typing import Final
+
+
+DEFAULT_TIMEOUT: Final[float] = 20

platypush/plugins/music/mopidy/_conf.py

@@ -0,0 +1,23 @@
+from dataclasses import dataclass
+from typing import Optional
+
+from ._common import DEFAULT_TIMEOUT
+
+
+@dataclass
+class MopidyConfig:
+    """
+    Mopidy configuration.
+    """
+
+    host: str = 'localhost'
+    port: int = 6680
+    ssl: bool = False
+    timeout: Optional[float] = DEFAULT_TIMEOUT
+
+    @property
+    def url(self) -> str:
+        return f'ws{"s" if self.ssl else ""}://{self.host}:{self.port}/mopidy/ws'
+
+
+# vim:sw=4:ts=4:et:

platypush/plugins/music/mopidy/_exc.py

@@ -0,0 +1,10 @@
+class MopidyException(Exception):
+    """
+    Base class for all Mopidy exceptions.
+    """
+
+
+class EmptyTrackException(MopidyException, ValueError):
+    """
+    Raised when a parsed track is empty.
+    """

platypush/plugins/music/mopidy/_playlist.py

@@ -0,0 +1,33 @@
+from dataclasses import dataclass, field
+from datetime import datetime
+from typing import List, Optional
+
+from platypush.schemas.mopidy import MopidyPlaylistSchema
+
+from ._track import MopidyTrack
+
+
+@dataclass
+class MopidyPlaylist:
+    """
+    Model for a Mopidy playlist.
+    """
+
+    uri: str
+    name: str
+    last_modified: Optional[datetime] = None
+    tracks: List[MopidyTrack] = field(default_factory=list)
+    type: str = "playlist"
+
+    @classmethod
+    def parse(cls, playlist: dict) -> "MopidyPlaylist":
+        """
+        Parse a Mopidy playlist from a dictionary received from the Mopidy API.
+        """
+        return cls(**MopidyPlaylistSchema().load(playlist))  # type: ignore
+
+    def to_dict(self) -> dict:
+        """
+        Convert the Mopidy playlist to a dictionary.
+        """
+        return dict(MopidyPlaylistSchema().dump(self))

platypush/plugins/music/mopidy/_status.py

@@ -0,0 +1,47 @@
+from dataclasses import asdict, dataclass
+from typing import Optional
+
+from platypush.plugins.media import PlayerState
+from platypush.schemas.mopidy import MopidyStatusSchema
+
+from ._track import MopidyTrack
+
+
+@dataclass
+class MopidyStatus:
+    """
+    A dataclass to hold the status of the Mopidy client.
+    """
+
+    state: PlayerState = PlayerState.STOP
+    volume: float = 0
+    consume: bool = False
+    random: bool = False
+    repeat: bool = False
+    single: bool = False
+    mute: bool = False
+    time: Optional[float] = None
+    duration: Optional[float] = None
+    playing_pos: Optional[int] = None
+    track: Optional[MopidyTrack] = None
+
+    def copy(self):
+        return MopidyStatus(
+            state=self.state,
+            volume=self.volume,
+            consume=self.consume,
+            random=self.random,
+            repeat=self.repeat,
+            single=self.single,
+            mute=self.mute,
+            time=self.time,
+            duration=self.duration,
+            playing_pos=self.playing_pos,
+            track=MopidyTrack(**asdict(self.track)) if self.track else None,
+        )
+
+    def to_dict(self):
+        """
+        Convert the Mopidy status to a dictionary.
+        """
+        return dict(MopidyStatusSchema().dump(self))

platypush/plugins/music/mopidy/_sync.py

@@ -0,0 +1,50 @@
+from dataclasses import dataclass, field
+from threading import Event, RLock
+from typing import Optional
+
+
+@dataclass
+class PlaylistSync:
+    """
+    Object used to synchronize playlist load/change events between threads.
+    """
+
+    _loading_lock: RLock = field(default_factory=RLock)
+    _loading: Event = field(default_factory=Event)
+    _loaded: Event = field(default_factory=Event)
+
+    def wait_for_loading(self, timeout: Optional[float] = None):
+        """
+        Wait for the playlist to be loaded.
+
+        :param timeout: The maximum time to wait for the playlist to be loaded.
+        """
+        # If the loading event is not set, no playlist change - we can proceed
+        # with notifying the event.
+        if not self._loading.is_set():
+            return True
+
+        # Wait for the full playlist to be loaded.
+        return self._loaded.wait(timeout)
+
+    def __enter__(self):
+        """
+        Called when entering a context manager to handle a playlist loading
+        session.
+        """
+        self._loading_lock.acquire()
+        self._loading.set()
+        self._loaded.clear()
+
+    def __exit__(self, *_):
+        """
+        Called when exiting a context manager to handle a playlist loading
+        session.
+        """
+        self._loading.clear()
+        self._loaded.set()
+
+        try:
+            self._loading_lock.release()
+        except RuntimeError:
+            pass

platypush/plugins/music/mopidy/_task.py

@@ -0,0 +1,58 @@
+import json
+from dataclasses import dataclass, field
+from queue import Queue
+from threading import Event
+from typing import Any, Optional, Union
+
+from websocket import WebSocketApp
+
+from ._common import DEFAULT_TIMEOUT
+
+
+@dataclass
+class MopidyTask:
+    """
+    A task to be executed by the Mopidy client.
+    """
+
+    id: int
+    method: str
+    args: dict = field(default_factory=dict)
+    response: Optional[Any] = None
+    response_ready: Event = field(default_factory=Event)
+    response_queue: Queue = field(default_factory=Queue)
+
+    def to_dict(self):
+        return {
+            "jsonrpc": "2.0",
+            "id": self.id,
+            "method": self.method,
+            'params': self.args,
+        }
+
+    def __str__(self):
+        return json.dumps(self.to_dict())
+
+    def send(self, ws: WebSocketApp):
+        assert ws, "Websocket connection not established"
+        self.response_ready.clear()
+        ws.send(str(self))
+
+    def get_response(self, timeout: Optional[float] = DEFAULT_TIMEOUT) -> Any:
+        ret = self.response_queue.get(timeout=timeout)
+        if isinstance(ret, dict):
+            ret = ret.get('result')
+
+        return ret
+
+    def put_response(self, response: Union[dict, Exception]):
+        self.response = response
+        self.response_ready.set()
+        self.response_queue.put_nowait(response)
+
+    def wait(self, timeout: Optional[float] = DEFAULT_TIMEOUT) -> bool:
+        return self.response_ready.wait(timeout=timeout)
+
+    def run(self, ws: WebSocketApp, timeout: Optional[float] = DEFAULT_TIMEOUT):
+        self.send(ws)
+        return self.get_response(timeout=timeout)

platypush/plugins/music/mopidy/_track.py

@@ -0,0 +1,43 @@
+from dataclasses import dataclass
+from typing import Optional
+
+from platypush.schemas.mopidy import MopidyTrackSchema
+
+from ._exc import EmptyTrackException
+
+
+@dataclass
+class MopidyTrack:
+    """
+    Model for a Mopidy track.
+    """
+
+    uri: str
+    artist: Optional[str] = None
+    title: Optional[str] = None
+    album: Optional[str] = None
+    artist_uri: Optional[str] = None
+    album_uri: Optional[str] = None
+    time: Optional[float] = None
+    playlist_pos: Optional[int] = None
+    track_id: Optional[int] = None
+    track_no: Optional[int] = None
+    date: Optional[str] = None
+    genre: Optional[str] = None
+    type: str = 'track'
+
+    @classmethod
+    def parse(cls, track: dict) -> Optional["MopidyTrack"]:
+        """
+        Parse a Mopidy track from a dictionary received from the Mopidy API.
+        """
+        try:
+            return cls(**MopidyTrackSchema().load(track))  # type: ignore
+        except EmptyTrackException:
+            return None
+
+    def to_dict(self) -> dict:
+        """
+        Convert the Mopidy track to a dictionary.
+        """
+        return dict(MopidyTrackSchema().dump(self))

platypush/plugins/music/mopidy/manifest.yaml

@@ -13,5 +13,5 @@ manifest:
     platypush.message.event.music.VolumeChangeEvent: if the main volume has changed
   install:
     pip: []
-  package: platypush.backend.music.mopidy
+  package: platypush.plugins.music.mopidy
-  type: backend
+  type: plugin

platypush/plugins/music/mpd/__init__.py

@@ -21,6 +21,18 @@ class MusicMpdPlugin(MusicPlugin, RunnablePlugin):
     the original protocol and with support for multiple music sources through
     plugins (e.g. Spotify, TuneIn, Soundcloud, local files etc.).
 
+    .. note:: If you use Mopidy, and unless you have quite specific use-cases
+        (like you don't want to expose the Mopidy HTTP interface, or you have
+        some legacy automation that uses the MPD interface), you should use the
+        :class:`platypush.plugins.music.mopidy.MusicMopidyPlugin` plugin instead
+        of this. The Mopidy plugin provides a more complete and feature-rich
+        experience, as not all the features of Mopidy are available through the
+        MPD interface, and its API is 100% compatible with this plugin. Also,
+        this plugin operates a synchronous/polling logic because of the
+        limitations of the MPD protocol, while the Mopidy plugin, as it uses the
+        Mopidy Websocket API, can operate in a more efficient way and provide
+        real-time updates.
+
     .. note:: As of Mopidy 3.0 MPD is an optional interface provided by the
         ``mopidy-mpd`` extension. Make sure that you have the extension
         installed and enabled on your instance to use this plugin if you want to
@@ -645,11 +657,12 @@ class MusicMpdPlugin(MusicPlugin, RunnablePlugin):
         self._exec('rename', playlist, new_name)
 
     @action
-    def lsinfo(self, uri: Optional[str] = None):
+    def browse(self, uri: Optional[str] = None):
-        """
-        Returns the list of playlists and directories on the server.
         """
+        Browse the items under the specified URI.
 
+        :param uri: URI to browse (default: root directory).
+        """
         return (
             self._exec('lsinfo', uri, return_status=False)
             if uri

platypush/schemas/mopidy.py

@@ -0,0 +1,325 @@
+from marshmallow import EXCLUDE, fields, post_dump, post_load, pre_dump, pre_load
+from marshmallow.schema import Schema
+
+from platypush.plugins.media import PlayerState
+from platypush.schemas import DateTime
+
+
+class MopidyTrackSchema(Schema):
+    """
+    Mopidy track schema.
+    """
+
+    uri = fields.String(required=True, metadata={"description": "Track URI"})
+    file = fields.String(
+        metadata={"description": "Track URI, for MPD compatibility purposes"}
+    )
+    artist = fields.String(missing=None, metadata={"description": "Artist name"})
+    title = fields.String(missing=None, metadata={"description": "Track title"})
+    album = fields.String(missing=None, metadata={"description": "Album name"})
+    artist_uri = fields.String(
+        missing=None, metadata={"description": "Artist URI (if available)"}
+    )
+    album_uri = fields.String(
+        missing=None, metadata={"description": "Album URI (if available)"}
+    )
+    time = fields.Float(
+        missing=None, metadata={"description": "Track length (in seconds)"}
+    )
+    playlist_pos = fields.Integer(
+        missing=None,
+        metadata={"description": "Track position in the tracklist/playlist"},
+    )
+    track_id = fields.Integer(
+        missing=None, metadata={"description": "Track ID in the current tracklist"}
+    )
+    track_no = fields.Integer(
+        missing=None, metadata={"description": "Track number in the album"}
+    )
+    date = fields.String(missing=None, metadata={"description": "Track release date"})
+    genre = fields.String(missing=None, metadata={"description": "Track genre"})
+    type = fields.Constant("track", metadata={"description": "Item type"})
+
+    @pre_load
+    def parse(self, track: dict, **_):
+        from platypush.plugins.music.mopidy import EmptyTrackException
+
+        uri = (track or {}).get("uri", (track or {}).get("track", {}).get("uri"))
+        if not uri:
+            raise EmptyTrackException("Empty track")
+
+        tlid = track.get("tlid")
+        playlist_pos = track.get("playlist_pos")
+        if track.get("track"):
+            track = track.get("track", {})
+
+        length = track.get("length", track.get("time", track.get("duration")))
+        return {
+            "uri": uri,
+            "artist": next(
+                iter(item.get("name") for item in track.get("artists", [])),
+                None,
+            ),
+            "title": track.get("name"),
+            "album": track.get("album", {}).get("name"),
+            "artist_uri": next(
+                iter(item.get("uri") for item in track.get("artists", [])), None
+            ),
+            "album_uri": track.get("album", {}).get("uri"),
+            "time": length / 1000 if length is not None else None,
+            "playlist_pos": (
+                track.get("playlist_pos") if playlist_pos is None else playlist_pos
+            ),
+            "date": track.get("date", track.get("album", {}).get("date")),
+            "track_id": tlid,
+            "track_no": track.get("track_no"),
+            "genre": track.get("genre"),
+        }
+
+    @post_dump
+    def to_dict(self, track: dict, **_):
+        """
+        Fill/move missing fields in the dictionary.
+        """
+        return {
+            "file": track["uri"],
+            **track,
+        }
+
+
+class MopidyStatusSchema(Schema):
+    """
+    Mopidy status schema.
+    """
+
+    state = fields.Enum(
+        PlayerState,
+        required=True,
+        metadata={"description": "Player state"},
+    )
+    volume = fields.Float(metadata={"description": "Player volume (0-100)"})
+    consume = fields.Boolean(metadata={"description": "Consume mode"})
+    random = fields.Boolean(metadata={"description": "Random mode"})
+    repeat = fields.Boolean(metadata={"description": "Repeat mode"})
+    single = fields.Boolean(metadata={"description": "Single mode"})
+    mute = fields.Boolean(metadata={"description": "Mute mode"})
+    time = fields.Float(metadata={"description": "Current time (in seconds)"})
+    playing_pos = fields.Integer(
+        metadata={"description": "Index of the currently playing track"}
+    )
+    track = fields.Nested(
+        MopidyTrackSchema, missing=None, metadata={"description": "Current track"}
+    )
+
+    @post_dump
+    def post_dump(self, data: dict, **_):
+        """
+        Post-dump hook.
+        """
+        state = data.get("state")
+        if state:
+            data["state"] = getattr(PlayerState, state).value
+        return data
+
+
+class MopidyPlaylistSchema(Schema):
+    """
+    Mopidy playlist schema.
+    """
+
+    # pylint: disable=too-few-public-methods
+    class Meta:  # type: ignore
+        """
+        Mopidy playlist schema metadata.
+        """
+
+        unknown = EXCLUDE
+
+    uri = fields.String(required=True, metadata={"description": "Playlist URI"})
+    name = fields.String(required=True, metadata={"description": "Playlist name"})
+    last_modified = DateTime(metadata={"description": "Last modified timestamp"})
+    tracks = fields.List(
+        fields.Nested(MopidyTrackSchema),
+        missing=None,
+        metadata={"description": "Playlist tracks"},
+    )
+    type = fields.Constant("playlist", metadata={"description": "Item type"})
+
+    @pre_dump
+    def pre_dump(self, playlist, **_):
+        """
+        Pre-dump hook.
+        """
+        last_modified = (
+            playlist.last_modified
+            if hasattr(playlist, "last_modified")
+            else playlist.get("last_modified")
+        )
+
+        if last_modified:
+            last_modified /= 1000
+        if hasattr(playlist, "last_modified"):
+            playlist.last_modified = last_modified
+        else:
+            playlist["last_modified"] = last_modified
+
+        return playlist
+
+
+class MopidyArtistSchema(Schema):
+    """
+    Mopidy artist schema.
+    """
+
+    uri = fields.String(required=True, metadata={"description": "Artist URI"})
+    file = fields.String(
+        metadata={"description": "Artist URI, for MPD compatibility purposes"}
+    )
+    name = fields.String(missing=None, metadata={"description": "Artist name"})
+    artist = fields.String(
+        missing=None,
+        metadata={"description": "Same as name - for MPD compatibility purposes"},
+    )
+    type = fields.Constant("artist", metadata={"description": "Item type"})
+
+    @post_dump
+    def to_dict(self, artist: dict, **_):
+        """
+        Fill/move missing fields in the dictionary.
+        """
+        return {
+            "file": artist["uri"],
+            "artist": artist["name"],
+            **artist,
+        }
+
+
+class MopidyAlbumSchema(Schema):
+    """
+    Mopidy album schema.
+    """
+
+    uri = fields.String(required=True, metadata={"description": "Album URI"})
+    file = fields.String(
+        metadata={"description": "Artist URI, for MPD compatibility purposes"}
+    )
+    artist = fields.String(missing=None, metadata={"description": "Artist name"})
+    album = fields.String(
+        missing=None,
+        metadata={"description": "Same as name - for MPD compatibility purposes"},
+    )
+    name = fields.String(missing=None, metadata={"description": "Album name"})
+    artist_uri = fields.String(missing=None, metadata={"description": "Artist URI"})
+    date = fields.String(missing=None, metadata={"description": "Album release date"})
+    genre = fields.String(missing=None, metadata={"description": "Album genre"})
+
+    def parse(self, data: dict, **_):
+        assert data.get("uri"), "Album URI is required"
+        return {
+            "uri": data["uri"],
+            "artist": data.get("artist")
+            or next(
+                iter(item.get("name") for item in data.get("artists", [])),
+                None,
+            ),
+            "name": data.get("name"),
+            "artist_uri": data.get("artist_uri")
+            or next(iter(item.get("uri") for item in data.get("artists", [])), None),
+            "album_uri": data.get("album_uri") or data.get("album", {}).get("uri"),
+            "date": data.get("date", data.get("album", {}).get("date")),
+            "genre": data.get("genre"),
+        }
+
+    @pre_load
+    def pre_load(self, album: dict, **_):
+        """
+        Pre-load hook.
+        """
+        return self.parse(album)
+
+    @pre_dump
+    def pre_dump(self, album: dict, **_):
+        """
+        Pre-dump hook.
+        """
+        return self.parse(album)
+
+    @post_dump
+    def to_dict(self, album: dict, **_):
+        """
+        Fill/move missing fields in the dictionary.
+        """
+        return {
+            "file": album["uri"],
+            "album": album["name"],
+            **album,
+        }
+
+
+class MopidyDirectorySchema(Schema):
+    """
+    Mopidy directory schema.
+    """
+
+    uri = fields.String(required=True, metadata={"description": "Directory URI"})
+    name = fields.String(required=True, metadata={"description": "Directory name"})
+    type = fields.Constant("directory", metadata={"description": "Item type"})
+
+
+class MopidyFilterSchema(Schema):
+    """
+    Mopidy filter schema.
+    """
+
+    uris = fields.List(fields.String, metadata={"description": "Filter by URIs"})
+    artist = fields.List(fields.String, metadata={"description": "Artist name(s)"})
+    album = fields.List(fields.String, metadata={"description": "Album name(s)"})
+    title = fields.List(fields.String, metadata={"description": "Track title(s)"})
+    albumartist = fields.List(
+        fields.String, metadata={"description": "Album artist name(s)"}
+    )
+    date = fields.List(fields.String, metadata={"description": "Track release date(s)"})
+    genre = fields.List(fields.String, metadata={"description": "Genre(s)"})
+    comment = fields.List(fields.String, metadata={"description": "Comment(s)"})
+    disc_no = fields.List(fields.Integer, metadata={"description": "Disc number(s)"})
+    musicbrainz_artistid = fields.List(
+        fields.String, metadata={"description": "MusicBrainz artist ID(s)"}
+    )
+    musicbrainz_albumid = fields.List(
+        fields.String, metadata={"description": "MusicBrainz album ID(s)"}
+    )
+    musicbrainz_trackid = fields.List(
+        fields.String, metadata={"description": "MusicBrainz album artist ID(s)"}
+    )
+    any = fields.List(
+        fields.String, metadata={"description": "Generic search string(s)"}
+    )
+
+    @pre_load
+    def pre_load(self, data: dict, **_):
+        """
+        Pre-load hook.
+        """
+        for field_name, field in self.fields.items():
+            value = data.get(field_name)
+
+            # Back-compatibtility with MPD's single-value filters
+            if (
+                value is not None
+                and isinstance(field, fields.List)
+                and isinstance(value, str)
+            ):
+                data[field_name] = [value]
+
+        return data
+
+    @post_load
+    def post_load(self, data: dict, **_):
+        """
+        Post-load hook.
+        """
+        title = data.pop("title", None)
+        if title:
+            data["track_name"] = title
+
+        return data

platypush/utils/threads.py

@@ -35,8 +35,11 @@ def OrEvent(*events, cls: Type = threading.Event):
         e.changed()
 
     def _or_set(e):
+        try:
             e._set()
             e.changed()
+        except RecursionError:
+            pass
 
     for e in events:
         _to_or(e, changed)