matrix-alertbot/matrix_alertbot/webhook.py
2022-08-08 12:38:09 +02:00

177 lines
6 KiB
Python

from __future__ import annotations
import logging
import prometheus_client
from aiohttp import ClientError, web, web_request
from aiohttp_prometheus_exporter.handler import metrics
from aiohttp_prometheus_exporter.middleware import prometheus_middleware_factory
from diskcache import Cache
from nio import AsyncClient, LocalProtocolError, SendRetryError
from matrix_alertbot.alert import Alert, AlertRenderer
from matrix_alertbot.alertmanager import AlertmanagerClient
from matrix_alertbot.chat_functions import send_text_to_room
from matrix_alertbot.config import Config
from matrix_alertbot.errors import (
AlertmanagerError,
SilenceExtendError,
SilenceNotFoundError,
)
logger = logging.getLogger(__name__)
routes = web.RouteTableDef()
@routes.get("/health")
async def get_health(request: web_request.Request) -> web.Response:
return web.Response(status=200)
@routes.post("/alerts/{room_id}")
async def create_alerts(request: web_request.Request) -> web.Response:
data = await request.json()
room_id = request.match_info["room_id"]
config: Config = request.app["config"]
if room_id not in config.allowed_rooms:
logger.error("Cannot send alerts to room ID {room_id}.")
return web.Response(
status=401, body=f"Cannot send alerts to room ID {room_id}."
)
if "alerts" not in data:
logger.error("Received data without 'alerts' key")
return web.Response(status=400, body="Data must contain 'alerts' key.")
alert_dicts = data["alerts"]
if not isinstance(data["alerts"], list):
alerts_type = type(alert_dicts).__name__
logger.error(f"Received data with invalid alerts type '{alerts_type}'.")
return web.Response(
status=400, body=f"Alerts must be a list, got '{alerts_type}'."
)
logger.info(f"Received {len(alert_dicts)} alerts for room ID {room_id}: {data}")
if len(data["alerts"]) == 0:
return web.Response(status=400, body="Alerts cannot be empty.")
alerts = []
for alert in alert_dicts:
try:
alert = Alert.from_dict(alert)
except KeyError as e:
logger.error(f"Cannot parse alert dict: {e}")
return web.Response(status=400, body=f"Invalid alert: {alert}.")
alerts.append(alert)
for alert in alerts:
try:
await create_alert(alert, room_id, request)
except AlertmanagerError as e:
logger.error(
f"An error occured with Alertmanager when handling alert with fingerprint {alert.fingerprint}: {e}"
)
return web.Response(
status=500,
body=f"An error occured with Alertmanager when handling alert with fingerprint {alert.fingerprint}.",
)
except (SendRetryError, LocalProtocolError, ClientError) as e:
logger.error(
f"Unable to send alert {alert.fingerprint} to Matrix room: {e}"
)
return web.Response(
status=500,
body=f"An error occured when sending alert with fingerprint '{alert.fingerprint}' to Matrix room.",
)
return web.Response(status=200)
async def create_alert(
alert: Alert, room_id: str, request: web_request.Request
) -> None:
alertmanager_client: AlertmanagerClient = request.app["alertmanager_client"]
alert_renderer: AlertRenderer = request.app["alert_renderer"]
matrix_client: AsyncClient = request.app["matrix_client"]
cache: Cache = request.app["cache"]
config: Config = request.app["config"]
if alert.firing:
try:
silence_id = await alertmanager_client.update_silence(alert.fingerprint)
logger.debug(
f"Extended silence ID {silence_id} for alert with fingerprint {alert.fingerprint}"
)
return
except SilenceNotFoundError as e:
logger.debug(
f"Unable to extend silence for alert with fingerprint {alert.fingerprint}: {e}"
)
cache.delete(alert.fingerprint)
except SilenceExtendError as e:
logger.debug(
f"Unable to extend silence for alert with fingerprint {alert.fingerprint}: {e}"
)
plaintext = alert_renderer.render(alert, html=False)
html = alert_renderer.render(alert, html=True)
event = await send_text_to_room(
matrix_client, room_id, plaintext, html, notice=False
)
if alert.firing:
cache.set(event.event_id, alert.fingerprint, expire=config.cache_expire_time)
else:
cache.delete(alert.fingerprint)
class Webhook:
def __init__(
self,
matrix_client: AsyncClient,
alertmanager_client: AlertmanagerClient,
cache: Cache,
config: Config,
) -> None:
self.app = web.Application(logger=logger)
self.app["matrix_client"] = matrix_client
self.app["alertmanager_client"] = alertmanager_client
self.app["config"] = config
self.app["cache"] = cache
self.app["alert_renderer"] = AlertRenderer(config.template_dir)
self.app.add_routes(routes)
prometheus_registry = prometheus_client.CollectorRegistry(auto_describe=True)
self.app.middlewares.append(
prometheus_middleware_factory(registry=prometheus_registry)
)
self.app.router.add_get("/metrics", metrics())
self.runner = web.AppRunner(self.app)
self.config = config
self.address = config.address
self.port = config.port
self.socket = config.socket
async def start(self) -> None:
await self.runner.setup()
site: web.BaseSite
if self.address and self.port:
site = web.TCPSite(self.runner, self.address, self.port)
logger.info(f"Listening on {self.address}:{self.port}")
elif self.socket:
site = web.UnixSite(self.runner, self.socket)
logger.info(f"Listening on unix://{self.socket}")
await site.start()
async def close(self) -> None:
await self.runner.cleanup()