First pass at implemenation with pagerduty webhooks

ops_bot/main.py

@@ -0,0 +1,103 @@
+import asyncio
+from typing import Any, Dict, Optional, cast
+
+import uvicorn
+from fastapi import Depends, FastAPI, HTTPException, Request, status
+from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
+from pydantic import BaseSettings
+
+from ops_bot import pagerduty
+from ops_bot.matrix import MatrixClient, MatrixClientSettings
+
+
+class BotSettings(BaseSettings):
+    bearer_token: str
+    routing_keys: Dict[str, str]
+
+    class Config:
+        env_prefix = "BOT_"
+        case_sensitive = False
+
+
+app = FastAPI()
+security = HTTPBearer()
+
+
+async def get_matrix_service(request: Request) -> MatrixClient:
+    """A helper to fetch the matrix client from the app state"""
+    return cast(MatrixClient, request.app.state.matrix_client)
+
+
+async def matrix_main(matrix_client: MatrixClient) -> None:
+    """Execs the matrix client asyncio task"""
+    workers = [asyncio.create_task(matrix_client.start())]
+    await asyncio.gather(*workers)
+
+
+@app.on_event("startup")
+async def startup_event() -> None:
+    bot_settings = BotSettings(_env_file=".env", _env_file_encoding="utf-8")
+    matrix_settings = MatrixClientSettings(_env_file=".env", _env_file_encoding="utf-8")
+    matrix_settings.join_rooms = list(bot_settings.routing_keys.values())
+    c = MatrixClient(settings=matrix_settings)
+    app.state.matrix_client = c
+    app.state.bot_settings = bot_settings
+    asyncio.create_task(matrix_main(c))
+
+
+@app.on_event("shutdown")
+async def shutdown_event() -> None:
+    await app.state.matrix_client.shutdown()
+
+
+@app.get("/")
+async def root() -> Dict[str, str]:
+    return {"message": "Hello World"}
+
+
+def authorize(
+    request: Request, credentials: HTTPAuthorizationCredentials = Depends(security)
+) -> bool:
+    bearer_token = request.app.state.bot_settings.bearer_token
+    if credentials.credentials != bearer_token:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect bearer token",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    return True
+
+
+def get_destination(bot_settings: BotSettings, routing_key: str) -> Optional[str]:
+    return bot_settings.routing_keys.get(routing_key, None)
+
+
+@app.post("/hook/pagerduty/{routing_key}")
+async def pagerduty_hook(
+    request: Request,
+    matrix_client: MatrixClient = Depends(get_matrix_service),
+    auth: bool = Depends(authorize),
+) -> Dict[str, str]:
+    payload: Any = await request.json()
+    room_id = get_destination(
+        request.app.state.bot_settings, request.path_params["routing_key"]
+    )
+    if room_id is None:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND, detail="Unknown routing key"
+        )
+    msg_plain, msg_formatted = pagerduty.parse_pagerduty_event(payload)
+    await matrix_client.room_send(
+        room_id,
+        msg_plain,
+        message_formatted=msg_formatted,
+    )
+    return {"message": msg_plain, "message_formatted": msg_formatted}
+
+
+def start_dev() -> None:
+    uvicorn.run("ops_bot.main:app", port=1111, host="127.0.0.1", reload=True)
+
+
+def start() -> None:
+    uvicorn.run("ops_bot.main:app", port=1111, host="0.0.0.0")  # nosec B104