refactor(gateway): run inbox and BYO polling from FastAPI lifespan

surfsense_backend/app/gateway/byo_long_poll.py

@@ -0,0 +1,94 @@
+"""FastAPI lifespan integration for self-hosted BYO Telegram long-polling."""
+
+from __future__ import annotations
+
+import asyncio
+import logging
+
+from sqlalchemy import select
+
+from app.config import config
+from app.db import ExternalChatPlatform, ExternalChatAccount, async_session_maker
+from app.gateway.accounts import account_token
+from app.gateway.runner import _run_telegram_account
+
+logger = logging.getLogger(__name__)
+
+_tasks: set[asyncio.Task[None]] = set()
+_shutdown_event: asyncio.Event | None = None
+
+
+async def _sleep_or_shutdown(seconds: float) -> None:
+    if _shutdown_event is None:
+        await asyncio.sleep(seconds)
+        return
+    try:
+        await asyncio.wait_for(_shutdown_event.wait(), timeout=seconds)
+    except TimeoutError:
+        return
+
+
+async def _byo_account_supervisor(account_id: int, token: str) -> None:
+    while _shutdown_event is None or not _shutdown_event.is_set():
+        try:
+            await _run_telegram_account(account_id, token)
+        except asyncio.CancelledError:
+            raise
+        except Exception:
+            logger.exception(
+                "BYO Telegram long-poll failed account_id=%s; retrying in 30s",
+                account_id,
+            )
+        await _sleep_or_shutdown(30)
+
+
+async def start_byo_long_poll_supervisors() -> None:
+    """Start one BYO long-poll supervisor per active non-system Telegram account."""
+
+    global _shutdown_event
+    if not config.GATEWAY_BYO_LONGPOLL_ENABLED:
+        return
+    if _tasks:
+        return
+
+    _shutdown_event = asyncio.Event()
+    async with async_session_maker() as session:
+        result = await session.execute(
+            select(ExternalChatAccount).where(
+                ExternalChatAccount.platform == ExternalChatPlatform.TELEGRAM,
+                ExternalChatAccount.is_system_account.is_(False),
+                ExternalChatAccount.suspended_at.is_(None),
+            )
+        )
+        accounts = list(result.scalars())
+
+    for account in accounts:
+        token = account_token(account)
+        if not token:
+            continue
+        task = asyncio.create_task(
+            _byo_account_supervisor(int(account.id), token),
+            name=f"gateway-byo-telegram-{account.id}",
+        )
+        _tasks.add(task)
+        task.add_done_callback(_tasks.discard)
+        logger.info("Started BYO Telegram long-poll supervisor account_id=%s", account.id)
+
+
+async def stop_byo_long_poll_supervisors() -> None:
+    """Cancel and await all BYO long-poll supervisors."""
+
+    global _shutdown_event
+    if _shutdown_event is not None:
+        _shutdown_event.set()
+    tasks = list(_tasks)
+    for task in tasks:
+        task.cancel()
+    if tasks:
+        try:
+            await asyncio.wait_for(asyncio.gather(*tasks, return_exceptions=True), timeout=10)
+        except TimeoutError:
+            logger.warning("Timed out waiting for BYO Telegram long-poll supervisors to stop")
+    _tasks.clear()
+    _shutdown_event = None
+