Adding websockets to the core script

README.md

@@ -40,7 +40,6 @@ The examples below uses `alsa-utils` to record and play audio:
 sudo apt-get install alsa-utils
 ```
 
-
 ## Remote Wake Word Detection
 
 Run the satellite with remote wake word detection:
@@ -186,5 +185,22 @@ Satellites can respond to events from the server by running commands:
 * `--timer-updated-command` - timer has been paused/unpaused or has time added/removed (json on stdin)
 * `--timer-cancelled-command` - timer has been cancelled (timer id on stdin)
 * `--timer-finished-command` - timer has finished (timer id on stdin)
+* `--websocket-host` - the hostname or IP address where the WebSocket event service will served on, default is `localhost`
+* `--websocket-port` - the port number the WebSocket event service will be served on, default is `8675`
+* `--enable-event-websockets` - enable the WebSocket event service to subscribe to satellite events, default is False
 
 For more advanced scenarios, use an event service (`--event-uri`). See `wyoming_satellite/example_event_client.py` for a basic client that just logs events.
+
+## Websocket Event Service
+
+In order to stream satellite events to a WebSocket client, run with the following configuration.
+
+```shell
+script/run \
+--name 'my satellite' \   
+--uri 'tcp://0.0.0.0:10700' \  
+--mic-command 'arecord -r 16000 -c 1 -f S16_LE -t raw' \   
+--snd-command 'aplay -r 22050 -c 1 -f S16_LE -t raw' \
+--enable-event-websockets True \
+--websocket-host '0.0.0.0'
+```

requirements.txt

@@ -1,3 +1,4 @@
 wyoming==1.5.4
 zeroconf==0.88.0
 pyring-buffer==1.0.0
+websockets==12.0

wyoming_satellite/__main__.py

@@ -2,11 +2,16 @@
 
 import argparse
 import asyncio
+import base64
+import json
 import logging
 import sys
 from functools import partial
+from typing import Optional
 from pathlib import Path
+import websockets
 
+from wyoming.event import Event
 from wyoming.info import Attribution, Info, Satellite
 from wyoming.server import AsyncServer, AsyncTcpServer
 
@@ -297,6 +302,12 @@ async def main() -> None:
         version=__version__,
         help="Print version and exit",
     )
+
+    # Websockets
+    parser.add_argument("--websocket-host", default="localhost")
+    parser.add_argument("--websocket-port", type=int, default=8675)
+    parser.add_argument("--enable-event-websockets", default=False)
+
     args = parser.parse_args()
 
     # Validate args
@@ -466,17 +477,62 @@ async def main() -> None:
         )
 
     satellite_task = asyncio.create_task(satellite.run(), name="satellite run")
+    queue: "asyncio.Queue[Optional[Event]]" = (
+        asyncio.Queue() if args.enable_event_websockets else None
+    )
 
     try:
-        await server.run(partial(SatelliteEventHandler, wyoming_info, satellite, args))
+        if args.enable_event_websockets:
+            async with websockets.serve(
+                partial(websocket_connected, queue),
+                args.websocket_host,
+                args.websocket_port,
+            ):
+                await server.run(
+                    partial(SatelliteEventHandler, wyoming_info, satellite, args, queue)
+                )
+        else:
+            await server.run(
+                partial(SatelliteEventHandler, wyoming_info, satellite, args, queue)
+            )
     except KeyboardInterrupt:
         pass
     finally:
+        if args.enable_event_websockets:
+            queue.put_nowait(None)
+
         await satellite.stop()
         await satellite_task
 
 
-# -----------------------------------------------------------------------------
+async def websocket_connected(queue: "asyncio.Queue[Optional[Event]]", websocket):
+    try:
+        while True:
+            event = await queue.get()
+            if event is None:
+                # Stop signal
+                break
+
+            await websocket.send(
+                json.dumps(
+                    {
+                        "type": event.type,
+                        "data": event.data or {},
+                        "payload": (
+                            base64.b64encode(event.payload)
+                            .decode("utf-8")
+                            .replace("'", '"')
+                            if event.payload
+                            else None
+                        ),
+                    },
+                    ensure_ascii=False,
+                )
+            )
+    except websockets.ConnectionClosed:
+        pass
+    except Exception:
+        _LOGGER.exception("Error in websocket handler")
 
 
 def run():

wyoming_satellite/event_handler.py

@@ -1,7 +1,9 @@
 """Wyoming event handler for satellites."""
 import argparse
+import asyncio
 import logging
 import time
+from typing import Optional
 
 from wyoming.event import Event
 from wyoming.info import Describe, Info
@@ -20,15 +22,18 @@ def __init__(
         wyoming_info: Info,
         satellite: SatelliteBase,
         cli_args: argparse.Namespace,
+        queue: asyncio.Queue[Optional[Event]] | None, 
         *args,
         **kwargs,
     ) -> None:
         super().__init__(*args, **kwargs)
 
         self.cli_args = cli_args
-        self.wyoming_info = wyoming_info
         self.client_id = str(time.monotonic_ns())
+        self.queue = queue
         self.satellite = satellite
+        self.wyoming_info = wyoming_info
+
 
     # -------------------------------------------------------------------------
 
@@ -46,6 +51,9 @@ async def handle_event(self, event: Event) -> bool:
             # New connection
             _LOGGER.debug("Connection cancelled: %s", self.client_id)
             return False
+
+        if self.queue:
+            await self.queue.put(event)
 
         await self.satellite.event_from_server(event)