From 80891eeda2d05632998b6b6e29c8c99c785680a5 Mon Sep 17 00:00:00 2001
From: Jean-Marie Mineau <jean-marie.mineau@protonmail.com>
Date: Tue, 5 Oct 2021 23:36:38 +0200
Subject: [PATCH] add webhook

---
 config.yaml.exp           |  4 +++-
 src/kassandra/__main__.py | 31 ++++++++++++++++++++++++++++---
 src/kassandra/config.py   |  4 +++-
 src/kassandra/webhook.py  | 35 +++++++++++++++++++++++++++++++++++
 4 files changed, 69 insertions(+), 5 deletions(-)
 create mode 100644 src/kassandra/webhook.py

diff --git a/config.yaml.exp b/config.yaml.exp
index 0860f93..f91e69d 100644
--- a/config.yaml.exp
+++ b/config.yaml.exp
@@ -2,7 +2,9 @@
 username: kassandra
 homeserver: https://matrix.org
 password: beware of greeks bearing gifts
-allert_rooms:
+port: 8000
+host: 127.0.0.1
+alert_rooms:
   - "#troy:matrix.org"
   - "#ithaca:matrix.org"
 ...
diff --git a/src/kassandra/__main__.py b/src/kassandra/__main__.py
index 66f648f..f7be0ae 100644
--- a/src/kassandra/__main__.py
+++ b/src/kassandra/__main__.py
@@ -1,9 +1,30 @@
 import argparse
 import asyncio
 
+from typing import (
+    Any,
+    NoReturn
+)
+
 from matrix_bot.client import Client
 from matrix_bot.invite_policy import WhiteList
 from .config import load_config
+from .webhook import run_webhook
+
+async def send_messages(
+    message_queue: asyncio.Queue[dict[str, Any]],
+    bot: Client,
+    rooms: list[str]
+)->NoReturn:
+    """
+        Read messages from a queue and send them via the bot.
+    """
+    while True:
+        message = await message_queue.get()
+        message = str(message)
+        for room in rooms:
+            await bot.send_message(room, message)
+        message_queue.task_done()
 
 async def main():
     parser = argparse.ArgumentParser()
@@ -11,20 +32,24 @@ async def main():
     args = parser.parse_args()
 
     config = load_config(args.config)
+    alert_queue = asyncio.Queue()
+
     client = await Client(
         config.username,
         config.homeserver,
         config.password
     )
-    invite_policy = await WhiteList(client, config.allert_rooms)
+    invite_policy = await WhiteList(client, config.alert_rooms)
     client.set_invite_policy(invite_policy)
 
     # Test:
-    for room in config.allert_rooms:
+    for room in config.alert_rooms:
         await client.send_message(room, f"Hello from {config.username}")
 
     await asyncio.gather(
-        client.run()
+        client.run(),
+        run_webhook(alert_queue, config.host, config.port),
+        send_messages(alert_queue, client, config.alert_rooms)
     )
 
 if __name__ == "__main__":
diff --git a/src/kassandra/config.py b/src/kassandra/config.py
index 92578ad..d695be9 100644
--- a/src/kassandra/config.py
+++ b/src/kassandra/config.py
@@ -10,7 +10,9 @@ class Config:
     username: str
     homeserver: str
     password: str
-    allert_rooms: list[str]
+    port: int
+    host: str
+    alert_rooms: list[str]
 
 def load_config(file:str)->Config:
     """
diff --git a/src/kassandra/webhook.py b/src/kassandra/webhook.py
new file mode 100644
index 0000000..709959c
--- /dev/null
+++ b/src/kassandra/webhook.py
@@ -0,0 +1,35 @@
+"""
+The webhook receiving the alerts from alertmanager.
+"""
+
+import asyncio
+import aiohttp.web
+import aiohttp.web_request
+
+from typing import (
+    Any,
+    NoReturn
+)
+
+ENDPOINT = "/webhook"
+
+async def run_webhook(
+    alert_queue: asyncio.Queue[dict[str, Any]],
+    host: str,
+    port: int
+)->NoReturn:
+    """
+        Run the webhook endpoint and put the alerts in the queue.
+    """
+
+    async def handler(request:aiohttp.web_request.Request):
+        alert = await request.json()
+        await alert_queue.put(alert)
+        return aiohttp.web.Response()
+
+    app = aiohttp.web.Application()
+    app.add_routes([aiohttp.web.post(ENDPOINT, handler)])
+    runner = aiohttp.web.AppRunner(app)
+    await runner.setup()
+    site = aiohttp.web.TCPSite(runner, host, port)
+    await site.start()