Implement YT websub subscription

endpoint.py

@@ -12,6 +12,7 @@ import pathlib
 import flask
 import persistqueue
 import tweepy
+import requests
 import xmltodict
 
 from twitivity import Twitivity, TwitivityError
@@ -39,8 +40,11 @@ callback_url = config.get('Twitter', 'callback_url')
 webhook_url = config.get('Twitter', 'webhook_url')
 environment_name = config.get('Twitter', 'environment_name')
 
+yt_webhook_url = config.get('YouTube', 'webhook_url')
 yt_channel_id = config.get('YouTube', 'channel_id')
 
+yt_websub_topic = 'https://www.youtube.com/xml/feeds/videos.xml?channel_id={0}'.format(yt_channel_id)
+
 
 def update_twitter_tokens(user_id, access_token):
     path = pathlib.Path(storage_path, 'tokens.json')
@@ -79,6 +83,16 @@ def setup_twitter_webhook(api):
     return True
 
 
+def setup_youtube_webhook():
+    r = requests.post('https://pubsubhubbub.appspot.com/subscribe', data={
+        'hub.mode': 'subscribe',
+        'hub.topic': yt_websub_topic,
+        'hub.callback': yt_webhook_url,
+        'hub.verify': 'async',
+    })
+    return r.status_code in (202, 204)
+
+
 def push_event(data):
     queue = persistqueue.SQLiteQueue(storage_path)
     queue.put(data)
@@ -145,8 +159,7 @@ def youtube_webhook_get():
     mode = flask.request.args.get('hub.mode')
     topic = flask.request.args.get('hub.topic')
     challenge = flask.request.args.get('hub.challenge')
-    if (topic != 'https://www.youtube.com/xml/feeds/videos.xml?channel_id={0}'.format(yt_channel_id) or
+    if topic != yt_websub_topic or mode not in ('subscribe', 'unsubscribe') or not challenge:
-            mode not in ('subscribe', 'unsubscribe') or not challenge):
         return 'Invalid request', 403
     return challenge, 200