Fix MongoDB event loop handling

doorboy.py

@@ -9,22 +9,27 @@ import const
 
 app = Sanic(__name__)
 
-mongodb = AsyncIOMotorClient(const.MONGO_URI)
-db = mongodb.get_default_database()
-
 DOORBOY_SECRET = os.environ["DOORBOY_SECRET"]
 
 assert len(DOORBOY_SECRET) > 10
 
+
+@app.listener("before_server_start")
+async def setup_db(app, loop):
+    # TODO: find cleaner way to do this, for more see
+    # https://github.com/sanic-org/sanic/issues/919
+    app.db = AsyncIOMotorClient(const.MONGO_URI).get_default_database()
+
+
 @app.route("/allowed")
 async def view_doorboy_uids(request):
     if request.headers.get('KEY') != DOORBOY_SECRET:
         return text("how about no")
     allowed_names = []
-    async for obj in db.member.find({"enabled": True}):
+    async for obj in app.db.member.find({"enabled": True}):
         allowed_names.append(obj["_id"])
     allowed_uids = []
-    async for obj in db.inventory.find({"token.uid_hash": {"$exists":True}, "inventory.owner": {"$exists":True}, "token.enabled": {"$exists":True}}, {"inventory.owner": True, "token.uid_hash": True }):
+    async for obj in app.db.inventory.find({"token.uid_hash": {"$exists":True}, "inventory.owner": {"$exists":True}, "token.enabled": {"$exists":True}}, {"inventory.owner": True, "token.uid_hash": True }):
         if obj["inventory"].pop("owner").get("foreign_id") in allowed_names:
             del obj["_id"]
             del obj["inventory"]
@@ -49,7 +54,7 @@ async def view_longpoll(request):
             }
         ]
         try:
-            async with db.eventlog.watch(pipeline) as stream:
+            async with app.db.eventlog.watch(pipeline) as stream:
                 await response.write("data: watch-stream-opened\n\n")
                 async for event in stream:
                     if event["fullDocument"].get("type") == "open-door":