ria-toolkit-oss/src/ria_toolkit_oss/agent/ws_client.py
2026-04-16 11:13:43 -04:00

129 lines
4.7 KiB
Python

"""Persistent WebSocket client for the streamer agent.
Handles connection lifecycle: connect, heartbeat, auto-reconnect on drop.
The caller drives the I/O loop via ``run()`` with a message handler callback.
"""
from __future__ import annotations
import asyncio
import json
import logging
from typing import Awaitable, Callable
logger = logging.getLogger("ria_agent.ws")
MessageHandler = Callable[[dict], Awaitable[None]]
HeartbeatBuilder = Callable[[], dict]
BinaryHandler = Callable[[bytes], Awaitable[None]]
class WsClient:
"""Persistent WebSocket connection with heartbeat and auto-reconnect.
``url`` should be a full ``wss://host/path`` (or ``ws://``) URL. ``token``
is sent as a bearer in the ``Authorization`` header on connect.
"""
def __init__(
self,
url: str,
token: str,
*,
heartbeat_interval: float = 30.0,
reconnect_pause: float = 5.0,
) -> None:
self.url = url
self.token = token
self.heartbeat_interval = heartbeat_interval
self.reconnect_pause = reconnect_pause
self._ws = None
self._stop = asyncio.Event()
# ------------------------------------------------------------------
async def _connect(self):
import websockets
headers = [("Authorization", f"Bearer {self.token}")] if self.token else None
# websockets >= 12 accepts additional_headers; fall back to extra_headers for older versions.
try:
return await websockets.connect(self.url, additional_headers=headers)
except TypeError:
return await websockets.connect(self.url, extra_headers=headers)
# ------------------------------------------------------------------
async def send_json(self, payload: dict) -> None:
if self._ws is None:
raise ConnectionError("WebSocket is not connected")
await self._ws.send(json.dumps(payload))
async def send_bytes(self, data: bytes) -> None:
if self._ws is None:
raise ConnectionError("WebSocket is not connected")
await self._ws.send(data)
def stop(self) -> None:
self._stop.set()
# ------------------------------------------------------------------
async def run(
self,
on_message: MessageHandler,
heartbeat: HeartbeatBuilder,
on_binary: BinaryHandler | None = None,
) -> None:
"""Main loop: connect, heartbeat, dispatch messages, reconnect on drop."""
while not self._stop.is_set():
try:
self._ws = await self._connect()
logger.info("Connected to %s", self.url)
hb_task = asyncio.create_task(self._heartbeat_loop(heartbeat))
try:
async for raw in self._ws:
if isinstance(raw, bytes):
if on_binary is None:
logger.debug("Discarding unexpected %d-byte binary frame", len(raw))
continue
try:
await on_binary(raw)
except Exception:
logger.exception("on_binary handler raised; dropping frame")
continue
try:
msg = json.loads(raw)
except json.JSONDecodeError:
logger.warning("Malformed control frame: %r", raw[:200])
continue
await on_message(msg)
finally:
hb_task.cancel()
try:
await hb_task
except (asyncio.CancelledError, Exception):
pass
except asyncio.CancelledError:
raise
except Exception as exc:
if self._stop.is_set():
break
logger.warning("WS error: %s — reconnecting in %.1fs", exc, self.reconnect_pause)
finally:
try:
if self._ws is not None:
await self._ws.close()
except Exception:
pass
self._ws = None
if self._stop.is_set():
break
await asyncio.sleep(self.reconnect_pause)
async def _heartbeat_loop(self, heartbeat: HeartbeatBuilder) -> None:
while True:
try:
await self.send_json(heartbeat())
except Exception as exc:
logger.debug("Heartbeat send failed: %s", exc)
return
await asyncio.sleep(self.heartbeat_interval)