From 360ef894a75c3dfa91867e5e74959a0c207aff04 Mon Sep 17 00:00:00 2001 From: Thijs Putman Date: Mon, 27 Nov 2023 18:35:46 +0100 Subject: [PATCH] Use non-persistent connection for MPD (#94507) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * Do not use a persistent connection to MPD In other words, don't rely on the connection management provided by "python-mpd2". Instead of keeping the connection to MPD open, we explicitly connect before and disconnect after each command. There is probably a bit of overhead to this, but as the integration uses a local-polling approach to begin with, no functionality is lost or degraded. This change greatly hardens the MPD integration against both network issues and problems with the daemon itself. All connection-related failure modes have effectively been removed. * Update state retrieval methods Only "async_get_media_image" attempts to connect, all others are either called from there, or from the main "async_update" method (see previous commit) which also attempts to connect. So, this commit mainly revolves around gracefully handling situations where no connection is available when trying to retrieve MPD state. Finally, note the removal of "self._commands". This property is only used at the start of "_async_get_file_image_response" and was thus changed into a local variable. * Update media-player control methods These all need to explicitly connect to MPD as part of their flow. * Correct ruff failure (auto-fixed) * Use "async_timeout.timeout" context manager * Minor changes * Replace "async_timeout" with "asyncio.timeout" * Initialise "self._status" to empty dictionary Used to be initialised as None, which caused "NoneType is not iterable" type of issues in case of an unexpected disconnect (at which point status gets set to None again). Instead of guarding against None everywhere, using an empty dictionary seemed more prudent... Furthermore, more cautiously access its members to prevent potential KeyError-s in similar cases. * Fix livelock in "async_mute_volume()" This method doesn't need a connection; it calls into two other methods that actually connect to MPD – attempting to connect from here resulted in a livelock. --- homeassistant/components/mpd/media_player.py | 328 +++++++++++-------- 1 file changed, 191 insertions(+), 137 deletions(-) diff --git a/homeassistant/components/mpd/media_player.py b/homeassistant/components/mpd/media_player.py index 8eab83b5d41..9b3adb38e0c 100644 --- a/homeassistant/components/mpd/media_player.py +++ b/homeassistant/components/mpd/media_player.py @@ -1,11 +1,13 @@ """Support to interact with a Music Player Daemon.""" from __future__ import annotations -from contextlib import suppress +import asyncio +from contextlib import asynccontextmanager, suppress from datetime import timedelta import hashlib import logging import os +from socket import gaierror from typing import Any import mpd @@ -92,11 +94,11 @@ class MpdDevice(MediaPlayerEntity): self._name = name self.password = password - self._status = None + self._status = {} self._currentsong = None self._playlists = None self._currentplaylist = None - self._is_connected = False + self._is_available = None self._muted = False self._muted_volume = None self._media_position_updated_at = None @@ -104,67 +106,88 @@ class MpdDevice(MediaPlayerEntity): self._media_image_hash = None # Track if the song changed so image doesn't have to be loaded every update. self._media_image_file = None - self._commands = None # set up MPD client self._client = MPDClient() self._client.timeout = 30 - self._client.idletimeout = None + self._client.idletimeout = 10 + self._client_lock = asyncio.Lock() - async def _connect(self): - """Connect to MPD.""" - try: - await self._client.connect(self.server, self.port) - - if self.password is not None: - await self._client.password(self.password) - except mpd.ConnectionError: - return - - self._is_connected = True - - def _disconnect(self): - """Disconnect from MPD.""" - with suppress(mpd.ConnectionError): - self._client.disconnect() - self._is_connected = False - self._status = None - - async def _fetch_status(self): - """Fetch status from MPD.""" - self._status = await self._client.status() - self._currentsong = await self._client.currentsong() - await self._async_update_media_image_hash() - - if (position := self._status.get("elapsed")) is None: - position = self._status.get("time") - - if isinstance(position, str) and ":" in position: - position = position.split(":")[0] - - if position is not None and self._media_position != position: - self._media_position_updated_at = dt_util.utcnow() - self._media_position = int(float(position)) - - await self._update_playlists() - - @property - def available(self): - """Return true if MPD is available and connected.""" - return self._is_connected + # Instead of relying on python-mpd2 to maintain a (persistent) connection to + # MPD, the below explicitly sets up a *non*-persistent connection. This is + # done to workaround the issue as described in: + # + @asynccontextmanager + async def connection(self): + """Handle MPD connect and disconnect.""" + async with self._client_lock: + try: + # MPDClient.connect() doesn't always respect its timeout. To + # prevent a deadlock, enforce an additional (slightly longer) + # timeout on the coroutine itself. + try: + async with asyncio.timeout(self._client.timeout + 5): + await self._client.connect(self.server, self.port) + except asyncio.TimeoutError as error: + # TimeoutError has no message (which hinders logging further + # down the line), so provide one. + raise asyncio.TimeoutError( + "Connection attempt timed out" + ) from error + if self.password is not None: + await self._client.password(self.password) + self._is_available = True + yield + except ( + asyncio.TimeoutError, + gaierror, + mpd.ConnectionError, + OSError, + ) as error: + # Log a warning during startup or when previously connected; for + # subsequent errors a debug message is sufficient. + log_level = logging.DEBUG + if self._is_available is not False: + log_level = logging.WARNING + _LOGGER.log( + log_level, "Error connecting to '%s': %s", self.server, error + ) + self._is_available = False + self._status = {} + # Also yield on failure. Handling mpd.ConnectionErrors caused by + # attempting to control a disconnected client is the + # responsibility of the caller. + yield + finally: + with suppress(mpd.ConnectionError): + self._client.disconnect() async def async_update(self) -> None: - """Get the latest data and update the state.""" - try: - if not self._is_connected: - await self._connect() - self._commands = list(await self._client.commands()) + """Get the latest data from MPD and update the state.""" + async with self.connection(): + try: + self._status = await self._client.status() + self._currentsong = await self._client.currentsong() + await self._async_update_media_image_hash() - await self._fetch_status() - except (mpd.ConnectionError, OSError, ValueError) as error: - # Cleanly disconnect in case connection is not in valid state - _LOGGER.debug("Error updating status: %s", error) - self._disconnect() + if (position := self._status.get("elapsed")) is None: + position = self._status.get("time") + + if isinstance(position, str) and ":" in position: + position = position.split(":")[0] + + if position is not None and self._media_position != position: + self._media_position_updated_at = dt_util.utcnow() + self._media_position = int(float(position)) + + await self._update_playlists() + except (mpd.ConnectionError, ValueError) as error: + _LOGGER.debug("Error updating status: %s", error) + + @property + def available(self) -> bool: + """Return true if MPD is available and connected.""" + return self._is_available is True @property def name(self): @@ -174,13 +197,13 @@ class MpdDevice(MediaPlayerEntity): @property def state(self) -> MediaPlayerState: """Return the media state.""" - if self._status is None: + if not self._status: return MediaPlayerState.OFF - if self._status["state"] == "play": + if self._status.get("state") == "play": return MediaPlayerState.PLAYING - if self._status["state"] == "pause": + if self._status.get("state") == "pause": return MediaPlayerState.PAUSED - if self._status["state"] == "stop": + if self._status.get("state") == "stop": return MediaPlayerState.OFF return MediaPlayerState.OFF @@ -259,20 +282,26 @@ class MpdDevice(MediaPlayerEntity): async def async_get_media_image(self) -> tuple[bytes | None, str | None]: """Fetch media image of current playing track.""" - if not (file := self._currentsong.get("file")): - return None, None - response = await self._async_get_file_image_response(file) - if response is None: - return None, None + async with self.connection(): + if self._currentsong is None or not (file := self._currentsong.get("file")): + return None, None - image = bytes(response["binary"]) - mime = response.get( - "type", "image/png" - ) # readpicture has type, albumart does not - return (image, mime) + with suppress(mpd.ConnectionError): + response = await self._async_get_file_image_response(file) + if response is None: + return None, None + + image = bytes(response["binary"]) + mime = response.get( + "type", "image/png" + ) # readpicture has type, albumart does not + return (image, mime) async def _async_update_media_image_hash(self): """Update the hash value for the media image.""" + if self._currentsong is None: + return + file = self._currentsong.get("file") if file == self._media_image_file: @@ -295,16 +324,21 @@ class MpdDevice(MediaPlayerEntity): self._media_image_file = file async def _async_get_file_image_response(self, file): - # not all MPD implementations and versions support the `albumart` and `fetchpicture` commands - can_albumart = "albumart" in self._commands - can_readpicture = "readpicture" in self._commands + # not all MPD implementations and versions support the `albumart` and + # `fetchpicture` commands. + commands = [] + with suppress(mpd.ConnectionError): + commands = list(await self._client.commands()) + can_albumart = "albumart" in commands + can_readpicture = "readpicture" in commands response = None # read artwork embedded into the media file if can_readpicture: try: - response = await self._client.readpicture(file) + with suppress(mpd.ConnectionError): + response = await self._client.readpicture(file) except mpd.CommandError as error: if error.errno is not mpd.FailureResponseCode.NO_EXIST: _LOGGER.warning( @@ -315,7 +349,8 @@ class MpdDevice(MediaPlayerEntity): # read artwork contained in the media directory (cover.{jpg,png,tiff,bmp}) if none is embedded if can_albumart and not response: try: - response = await self._client.albumart(file) + with suppress(mpd.ConnectionError): + response = await self._client.albumart(file) except mpd.CommandError as error: if error.errno is not mpd.FailureResponseCode.NO_EXIST: _LOGGER.warning( @@ -339,7 +374,7 @@ class MpdDevice(MediaPlayerEntity): @property def supported_features(self) -> MediaPlayerEntityFeature: """Flag media player features that are supported.""" - if self._status is None: + if not self._status: return MediaPlayerEntityFeature(0) supported = SUPPORT_MPD @@ -373,55 +408,64 @@ class MpdDevice(MediaPlayerEntity): """Update available MPD playlists.""" try: self._playlists = [] - for playlist_data in await self._client.listplaylists(): - self._playlists.append(playlist_data["playlist"]) + with suppress(mpd.ConnectionError): + for playlist_data in await self._client.listplaylists(): + self._playlists.append(playlist_data["playlist"]) except mpd.CommandError as error: self._playlists = None _LOGGER.warning("Playlists could not be updated: %s:", error) async def async_set_volume_level(self, volume: float) -> None: """Set volume of media player.""" - if "volume" in self._status: - await self._client.setvol(int(volume * 100)) + async with self.connection(): + if "volume" in self._status: + await self._client.setvol(int(volume * 100)) async def async_volume_up(self) -> None: """Service to send the MPD the command for volume up.""" - if "volume" in self._status: - current_volume = int(self._status["volume"]) + async with self.connection(): + if "volume" in self._status: + current_volume = int(self._status["volume"]) - if current_volume <= 100: - self._client.setvol(current_volume + 5) + if current_volume <= 100: + self._client.setvol(current_volume + 5) async def async_volume_down(self) -> None: """Service to send the MPD the command for volume down.""" - if "volume" in self._status: - current_volume = int(self._status["volume"]) + async with self.connection(): + if "volume" in self._status: + current_volume = int(self._status["volume"]) - if current_volume >= 0: - await self._client.setvol(current_volume - 5) + if current_volume >= 0: + await self._client.setvol(current_volume - 5) async def async_media_play(self) -> None: """Service to send the MPD the command for play/pause.""" - if self._status["state"] == "pause": - await self._client.pause(0) - else: - await self._client.play() + async with self.connection(): + if self._status.get("state") == "pause": + await self._client.pause(0) + else: + await self._client.play() async def async_media_pause(self) -> None: """Service to send the MPD the command for play/pause.""" - await self._client.pause(1) + async with self.connection(): + await self._client.pause(1) async def async_media_stop(self) -> None: """Service to send the MPD the command for stop.""" - await self._client.stop() + async with self.connection(): + await self._client.stop() async def async_media_next_track(self) -> None: """Service to send the MPD the command for next track.""" - await self._client.next() + async with self.connection(): + await self._client.next() async def async_media_previous_track(self) -> None: """Service to send the MPD the command for previous track.""" - await self._client.previous() + async with self.connection(): + await self._client.previous() async def async_mute_volume(self, mute: bool) -> None: """Mute. Emulated with set_volume_level.""" @@ -437,75 +481,82 @@ class MpdDevice(MediaPlayerEntity): self, media_type: MediaType | str, media_id: str, **kwargs: Any ) -> None: """Send the media player the command for playing a playlist.""" - if media_source.is_media_source_id(media_id): - media_type = MediaType.MUSIC - play_item = await media_source.async_resolve_media( - self.hass, media_id, self.entity_id - ) - media_id = async_process_play_media_url(self.hass, play_item.url) + async with self.connection(): + if media_source.is_media_source_id(media_id): + media_type = MediaType.MUSIC + play_item = await media_source.async_resolve_media( + self.hass, media_id, self.entity_id + ) + media_id = async_process_play_media_url(self.hass, play_item.url) - if media_type == MediaType.PLAYLIST: - _LOGGER.debug("Playing playlist: %s", media_id) - if media_id in self._playlists: - self._currentplaylist = media_id + if media_type == MediaType.PLAYLIST: + _LOGGER.debug("Playing playlist: %s", media_id) + if media_id in self._playlists: + self._currentplaylist = media_id + else: + self._currentplaylist = None + _LOGGER.warning("Unknown playlist name %s", media_id) + await self._client.clear() + await self._client.load(media_id) + await self._client.play() else: + await self._client.clear() self._currentplaylist = None - _LOGGER.warning("Unknown playlist name %s", media_id) - await self._client.clear() - await self._client.load(media_id) - await self._client.play() - else: - await self._client.clear() - self._currentplaylist = None - await self._client.add(media_id) - await self._client.play() + await self._client.add(media_id) + await self._client.play() @property def repeat(self) -> RepeatMode: """Return current repeat mode.""" - if self._status["repeat"] == "1": - if self._status["single"] == "1": + if self._status.get("repeat") == "1": + if self._status.get("single") == "1": return RepeatMode.ONE return RepeatMode.ALL return RepeatMode.OFF async def async_set_repeat(self, repeat: RepeatMode) -> None: """Set repeat mode.""" - if repeat == RepeatMode.OFF: - await self._client.repeat(0) - await self._client.single(0) - else: - await self._client.repeat(1) - if repeat == RepeatMode.ONE: - await self._client.single(1) - else: + async with self.connection(): + if repeat == RepeatMode.OFF: + await self._client.repeat(0) await self._client.single(0) + else: + await self._client.repeat(1) + if repeat == RepeatMode.ONE: + await self._client.single(1) + else: + await self._client.single(0) @property def shuffle(self): """Boolean if shuffle is enabled.""" - return bool(int(self._status["random"])) + return bool(int(self._status.get("random"))) async def async_set_shuffle(self, shuffle: bool) -> None: """Enable/disable shuffle mode.""" - await self._client.random(int(shuffle)) + async with self.connection(): + await self._client.random(int(shuffle)) async def async_turn_off(self) -> None: """Service to send the MPD the command to stop playing.""" - await self._client.stop() + async with self.connection(): + await self._client.stop() async def async_turn_on(self) -> None: """Service to send the MPD the command to start playing.""" - await self._client.play() - await self._update_playlists(no_throttle=True) + async with self.connection(): + await self._client.play() + await self._update_playlists(no_throttle=True) async def async_clear_playlist(self) -> None: """Clear players playlist.""" - await self._client.clear() + async with self.connection(): + await self._client.clear() async def async_media_seek(self, position: float) -> None: """Send seek command.""" - await self._client.seekcur(position) + async with self.connection(): + await self._client.seekcur(position) async def async_browse_media( self, @@ -513,8 +564,11 @@ class MpdDevice(MediaPlayerEntity): media_content_id: str | None = None, ) -> BrowseMedia: """Implement the websocket media browsing helper.""" - return await media_source.async_browse_media( - self.hass, - media_content_id, - content_filter=lambda item: item.media_content_type.startswith("audio/"), - ) + async with self.connection(): + return await media_source.async_browse_media( + self.hass, + media_content_id, + content_filter=lambda item: item.media_content_type.startswith( + "audio/" + ), + )