music-assistant-server

1"""Unified AirPlay/RAOP stream session logic for AirPlay devices."""
2
3from __future__ import annotations
4
5import asyncio
6import time
7from collections.abc import AsyncGenerator
8from contextlib import suppress
9from typing import TYPE_CHECKING
10
11from music_assistant_models.errors import PlayerCommandFailed
12
13from music_assistant.constants import CONF_SYNC_ADJUST
14from music_assistant.helpers.audio import get_player_filter_params
15from music_assistant.helpers.ffmpeg import FFMpeg
16from music_assistant.providers.airplay.helpers import ntp_to_unix_time, unix_time_to_ntp
17
18from .constants import (
19    AIRPLAY2_CONNECT_TIME_MS,
20    CONF_ENABLE_LATE_JOIN,
21    ENABLE_LATE_JOIN_DEFAULT,
22    RAOP_CONNECT_TIME_MS,
23    StreamingProtocol,
24)
25from .protocols.airplay2 import AirPlay2Stream
26from .protocols.raop import RaopStream
27
28if TYPE_CHECKING:
29    from music_assistant_models.media_items import AudioFormat
30
31    from .player import AirPlayPlayer
32    from .provider import AirPlayProvider
33
34
35class AirPlayStreamSession:
36    """Stream session (RAOP or AirPlay2) to one or more players."""
37
38    def __init__(
39        self,
40        airplay_provider: AirPlayProvider,
41        sync_clients: list[AirPlayPlayer],
42        pcm_format: AudioFormat,
43    ) -> None:
44        """Initialize AirPlayStreamSession.
45
46        :param airplay_provider: The AirPlay provider instance.
47        :param sync_clients: List of AirPlay players to stream to.
48        :param pcm_format: PCM format of the input stream.
49        """
50        assert sync_clients
51        self.prov = airplay_provider
52        self.mass = airplay_provider.mass
53        self.pcm_format = pcm_format
54        self.sync_clients = sync_clients
55        self._audio_source_task: asyncio.Task[None] | None = None
56        self._player_ffmpeg: dict[str, FFMpeg] = {}
57        self._lock = asyncio.Lock()
58        self.start_ntp: int = 0
59        self.start_time: float = 0.0
60        self.wait_start: float = 0.0
61        self.seconds_streamed: float = 0
62        self._first_chunk_received = asyncio.Event()
63
64    async def start(self, audio_source: AsyncGenerator[bytes, None]) -> None:
65        """Initialize stream session for all players."""
66        cur_time = time.time()
67        has_airplay2_client = any(
68            p.protocol == StreamingProtocol.AIRPLAY2 for p in self.sync_clients
69        )
70        wait_start = AIRPLAY2_CONNECT_TIME_MS if has_airplay2_client else RAOP_CONNECT_TIME_MS
71        wait_start_seconds = wait_start / 1000
72        self.wait_start = wait_start_seconds
73        self.start_time = cur_time + wait_start_seconds
74        self.start_ntp = unix_time_to_ntp(self.start_time)
75        await asyncio.gather(*[self._start_client(p, self.start_ntp) for p in self.sync_clients])
76        self._audio_source_task = asyncio.create_task(self._audio_streamer(audio_source))
77        try:
78            await asyncio.gather(
79                *[p.stream.wait_for_connection() for p in self.sync_clients if p.stream]
80            )
81        except Exception:
82            # playback failed to start, cleanup
83            await self.stop()
84            raise PlayerCommandFailed("Playback failed to start")
85
86    async def stop(self, force: bool = False) -> None:
87        """Stop playback and cleanup."""
88        if self._audio_source_task and not self._audio_source_task.done():
89            self._audio_source_task.cancel()
90            with suppress(asyncio.CancelledError):
91                await self._audio_source_task
92        if force:
93            await asyncio.gather(
94                *[self.stop_client(x, force=True) for x in self.sync_clients],
95            )
96            self.sync_clients = []
97        else:
98            await asyncio.gather(
99                *[self.remove_client(x) for x in self.sync_clients],
100            )
101
102    async def remove_client(self, airplay_player: AirPlayPlayer) -> None:
103        """Remove a sync client from the session."""
104        async with self._lock:
105            if airplay_player not in self.sync_clients:
106                return
107            self.sync_clients.remove(airplay_player)
108        await self.stop_client(airplay_player)
109        # If this was the last client, stop the session
110        if not self.sync_clients:
111            await self.stop()
112            return
113
114    async def stop_client(self, airplay_player: AirPlayPlayer, force: bool = False) -> None:
115        """
116        Stop a client's stream and ffmpeg.
117
118        :param airplay_player: The player to stop.
119        :param force: If True, kill CLI process immediately.
120        """
121        ffmpeg = self._player_ffmpeg.pop(airplay_player.player_id, None)
122        if force:
123            if ffmpeg and not ffmpeg.closed:
124                await ffmpeg.kill()
125            if airplay_player.stream and airplay_player.stream.session == self:
126                await airplay_player.stream.stop(force=True)
127        else:
128            if ffmpeg and not ffmpeg.closed:
129                await ffmpeg.close()
130            if airplay_player.stream and airplay_player.stream.session == self:
131                await airplay_player.stream.stop()
132
133    async def add_client(self, airplay_player: AirPlayPlayer) -> None:
134        """Add a sync client to the session as a late joiner.
135
136        The late joiner will:
137        1. Start playing at a compensated NTP timestamp (start_ntp + offset)
138        2. Receive silence calculated dynamically based on how much audio has been sent
139        3. Then receive real audio chunks in sync with other players
140        """
141        sync_leader = self.sync_clients[0]
142        if not sync_leader.stream or not sync_leader.stream.running:
143            return
144
145        allow_late_join = self.prov.config.get_value(
146            CONF_ENABLE_LATE_JOIN, ENABLE_LATE_JOIN_DEFAULT
147        )
148        if not allow_late_join:
149            await self.stop()
150            if sync_leader.state.current_media:
151                self.mass.call_later(
152                    0.5,
153                    self.mass.players.cmd_resume(sync_leader.player_id),
154                    task_id=f"resync_session_{sync_leader.player_id}",
155                )
156            return
157
158        async with self._lock:
159            skip_seconds = self.seconds_streamed
160            start_at = self.start_time + skip_seconds
161            start_ntp = unix_time_to_ntp(start_at)
162            if airplay_player not in self.sync_clients:
163                self.sync_clients.append(airplay_player)
164
165            await self._start_client(airplay_player, start_ntp)
166            if airplay_player.stream:
167                await airplay_player.stream.wait_for_connection()
168
169    async def _audio_streamer(self, audio_source: AsyncGenerator[bytes, None]) -> None:
170        """Stream audio to all players."""
171        pcm_sample_size = self.pcm_format.pcm_sample_size
172        watchdog_task = asyncio.create_task(self._silence_watchdog(pcm_sample_size))
173        try:
174            async for chunk in audio_source:
175                if not self._first_chunk_received.is_set():
176                    watchdog_task.cancel()
177                    with suppress(asyncio.CancelledError):
178                        await watchdog_task
179                    self._first_chunk_received.set()
180
181                if not self.sync_clients:
182                    break
183
184                await self._write_chunk_to_all_players(chunk)
185                self.seconds_streamed += len(chunk) / pcm_sample_size
186        finally:
187            if not watchdog_task.done():
188                watchdog_task.cancel()
189                with suppress(asyncio.CancelledError):
190                    await watchdog_task
191        async with self._lock:
192            await asyncio.gather(
193                *[
194                    self._write_eof_to_player(x)
195                    for x in self.sync_clients
196                    if x.stream and x.stream.running
197                ],
198                return_exceptions=True,
199            )
200
201    async def _silence_watchdog(self, pcm_sample_size: int) -> None:
202        """Insert silence if audio source is slow to deliver first chunk."""
203        grace_period = 0.2
204        max_silence_padding = 5.0
205        silence_inserted = 0.0
206
207        await asyncio.sleep(grace_period)
208        while not self._first_chunk_received.is_set() and silence_inserted < max_silence_padding:
209            silence_duration = 0.1
210            silence_bytes = int(pcm_sample_size * silence_duration)
211            silence_chunk = bytes(silence_bytes)
212            await self._write_chunk_to_all_players(silence_chunk)
213            self.seconds_streamed += silence_duration
214            silence_inserted += silence_duration
215            await asyncio.sleep(0.05)
216
217        if silence_inserted > 0:
218            self.prov.logger.warning(
219                "Inserted %.1fs silence padding while waiting for audio source",
220                silence_inserted,
221            )
222
223    async def _write_chunk_to_all_players(self, chunk: bytes) -> None:
224        """Write a chunk to all connected players."""
225        async with self._lock:
226            sync_clients = [x for x in self.sync_clients if x.stream and x.stream.running]
227            if not sync_clients:
228                return
229
230            # Write chunk to all players
231            write_tasks = [self._write_chunk_to_player(x, chunk) for x in sync_clients if x.stream]
232            results = await asyncio.gather(*write_tasks, return_exceptions=True)
233
234            # Check for write errors or timeouts
235            players_to_remove: list[AirPlayPlayer] = []
236            for i, result in enumerate(results):
237                if i >= len(sync_clients):
238                    continue
239                player = sync_clients[i]
240
241                if isinstance(result, TimeoutError):
242                    self.prov.logger.warning(
243                        "Removing player %s from session: stopped reading data (write timeout)",
244                        player.player_id,
245                    )
246                    players_to_remove.append(player)
247                elif isinstance(result, Exception):
248                    self.prov.logger.warning(
249                        "Removing player %s from session due to write error: %s",
250                        player.player_id,
251                        result,
252                    )
253                    players_to_remove.append(player)
254
255            for player in players_to_remove:
256                self.mass.create_task(self.remove_client(player))
257
258    async def _write_chunk_to_player(self, airplay_player: AirPlayPlayer, chunk: bytes) -> None:
259        """Write audio chunk to a player's ffmpeg process."""
260        player_id = airplay_player.player_id
261        if ffmpeg := self._player_ffmpeg.get(player_id):
262            if ffmpeg.closed:
263                return
264            await asyncio.wait_for(ffmpeg.write(chunk), timeout=35.0)
265
266    async def _write_eof_to_player(self, airplay_player: AirPlayPlayer) -> None:
267        """Write EOF to a specific player."""
268        if ffmpeg := self._player_ffmpeg.pop(airplay_player.player_id, None):
269            await ffmpeg.write_eof()
270            await ffmpeg.wait_with_timeout(30)
271            if airplay_player.stream and airplay_player.stream._cli_proc:
272                await airplay_player.stream._cli_proc.write_eof()
273
274    async def _start_client(self, airplay_player: AirPlayPlayer, start_ntp: int) -> None:
275        """Start CLI process and ffmpeg for a single client."""
276        if airplay_player.stream and airplay_player.stream.running:
277            await airplay_player.stream.stop()
278        if airplay_player.protocol == StreamingProtocol.AIRPLAY2:
279            airplay_player.stream = AirPlay2Stream(airplay_player)
280        else:
281            airplay_player.stream = RaopStream(airplay_player)
282        airplay_player.stream.session = self
283        sync_adjust = airplay_player.config.get_value(CONF_SYNC_ADJUST, 0)
284        assert isinstance(sync_adjust, int)
285        if sync_adjust != 0:
286            start_ntp = unix_time_to_ntp(ntp_to_unix_time(start_ntp) + (sync_adjust / 1000))
287        await airplay_player.stream.start(start_ntp)
288        # Start ffmpeg to feed audio to CLI stdin
289        if ffmpeg := self._player_ffmpeg.pop(airplay_player.player_id, None):
290            await ffmpeg.close()
291        filter_params = get_player_filter_params(
292            self.mass,
293            airplay_player.player_id,
294            self.pcm_format,
295            airplay_player.stream.pcm_format,
296        )
297        cli_proc = airplay_player.stream._cli_proc
298        assert cli_proc
299        assert cli_proc.proc
300        assert cli_proc.proc.stdin
301        stdin_transport = cli_proc.proc.stdin.transport
302        audio_output: str | int = stdin_transport.get_extra_info("pipe").fileno()
303        ffmpeg = FFMpeg(
304            audio_input="-",
305            input_format=self.pcm_format,
306            output_format=airplay_player.stream.pcm_format,
307            filter_params=filter_params,
308            audio_output=audio_output,
309        )
310        await ffmpeg.start()
311        self._player_ffmpeg[airplay_player.player_id] = ffmpeg
312