blueprints.channels: use ChannelDispatcher for MESSAGE_* events

- storage: add Storage.guild_from_channel

litecord/blueprints/channels.py

@@ -285,7 +285,9 @@ async def create_message(channel_id):
     # we really need dispatch_channel to make dm messages work,
     # since they aren't part of any existing guild.
     payload = await app.storage.get_message(message_id)
-    await app.dispatcher.dispatch_guild(guild_id, 'MESSAGE_CREATE', payload)
+
+    await app.dispatcher.dispatch('channel', channel_id,
+                                  'MESSAGE_CREATE', payload)
 
     # TODO: dispatch the MESSAGE_CREATE to any mentioning user.
 
@@ -330,7 +332,7 @@ async def edit_message(channel_id, message_id):
 
     # only dispatch MESSAGE_UPDATE if we actually had any update to start with
     if updated:
-        await app.dispatcher.dispatch_guild(guild_id,
+        await app.dispatcher.dispatch('channel', channel_id,
                                       'MESSAGE_UPDATE', message)
 
     return jsonify(message)
@@ -355,7 +357,9 @@ async def delete_message(channel_id, message_id):
     WHERE messages.id = $1
     """, message_id)
 
-    await app.dispatcher.dispatch_guild(guild_id, 'MESSAGE_DELETE', {
+    await app.dispatcher.dispatch(
+        'channel', channel_id,
+        'MESSAGE_DELETE', {
             'id': str(message_id),
             'channel_id': str(channel_id),
 

litecord/storage.py

@@ -840,3 +840,10 @@ class Storage:
             res.append(drow)
 
         return res
+
+    async def guild_from_channel(self, channel_id: int):
+        return await self.db.fetchval("""
+        SELECT guild_id
+        FROM guild_channels
+        WHERE id = $1
+        """, channel_id)