logout the matrix bot, comments

main.py

@@ -55,7 +55,7 @@ class MatrixClient(nio.AsyncClient):
         self.logger.info("Doing initial sync.")
         await self.sync(timeout)
 
-        # Set up event callbacks
+        # Set up event callbacks after syncing once to ignore old messages.
         callbacks = Callbacks(self)
 
         self.add_event_callback(
@@ -72,11 +72,14 @@ class MatrixClient(nio.AsyncClient):
             callbacks.typing_callback, nio.EphemeralEvent
         )
 
+        # Wait for Discord client...
         await discord_client.wait_until_ready()
 
         self.logger.info("Syncing forever.")
         await self.sync_forever(timeout=timeout)
 
+        # Logout
+        await self.logout()
         await self.close()
 
     async def upload_emote(self, emote_id):
@@ -202,13 +205,13 @@ height=\"32\" src=\"{emote_}\" data-mx-emoticon />"""
 
         hooks = await channel.webhooks()
 
-        # Create webhook if it doesn't exist
+        # Create webhook if it doesn't exist.
         hook = discord.utils.get(hooks, name=hook_name)
         if not hook:
             hook = await channel.create_webhook(name=hook_name)
 
-        # Username must be between 1 and 80 characters in length
+        # Username must be between 1 and 80 characters in length,
-        # 'wait=True' allows us to store the sent message
+        # 'wait=True' allows us to store the sent message.
         try:
             hook = await hook.send(
                 username=author[:80], avatar_url=avatar,
@@ -236,7 +239,12 @@ class DiscordClient(discord.ext.commands.Bot):
         self.add_cogs()
 
     def add_cogs(self):
-        for cog in os.listdir("./cogs"):
+        cogs_dir = "./cogs"
+
+        if not os.path.isdir(cogs_dir):
+            return
+
+        for cog in os.listdir(cogs_dir):
             if cog.endswith(".py"):
                 cog = f"cogs.{cog[:-3]}"
                 self.load_extension(cog)
@@ -259,6 +267,7 @@ class DiscordClient(discord.ext.commands.Bot):
             channel_store[channel] = self.get_channel(int(channel))
 
     async def on_message(self, message):
+        # Process other stuff like cogs before ignoring the message.
         await self.process_commands(message)
 
         if self.to_return(message.channel.id, message.author):
@@ -279,6 +288,7 @@ class DiscordClient(discord.ext.commands.Bot):
 
         content = await self.process_message(after)
 
+        # Edit message only if it can be looked up in the cache.
         if before.id in message_store:
             await self.matrix_client.message_send(
                 content[0], after.channel.id,
@@ -286,6 +296,7 @@ class DiscordClient(discord.ext.commands.Bot):
             )
 
     async def on_message_delete(self, message):
+        # Delete message only if it can be looked up in the cache.
         if message.id in message_store:
             await self.matrix_client.message_redact(
                 message_store[message.id], message.channel.id
@@ -306,23 +317,27 @@ class DiscordClient(discord.ext.commands.Bot):
         regex = r"<a?:(\w+):(\d+)>"
         emotes = {}
 
+        # Store all emotes in a dict to upload and insert into formatted body.
+        # { "emote_name": "emote_id" }
         for emote in re.findall(regex, content):
             emotes[emote[0]] = emote[1]
 
+        # Get message reference for replies.
         replied_event = None
         if message.reference:
             replied_message = await message.channel.fetch_message(
                 message.reference.message_id
             )
+            # Try to get the corresponding event from the message cache.
             try:
                 replied_event = message_store[replied_message.id]
             except KeyError:
                 pass
 
-        # Replace emote IDs with names
+        # Replace emote IDs with names.
         content = re.sub(regex, r":\g<1>:", content)
 
-        # Append attachments to message
+        # Append attachments to message.
         for attachment in message.attachments:
             content += f"\n{attachment.url}"
 
@@ -351,11 +366,13 @@ class Callbacks(object):
     async def message_callback(self, room, event):
         message = event.body
 
+        # Ignore messages having an empty body.
         if self.to_return(room, event) or not message:
             return
 
         content_dict = event.source.get("content")
 
+        # Get the corresponding Discord channel.
         channel_id = self.get_channel(room)
 
         author = room.user_name(event.sender)
@@ -366,14 +383,18 @@ class Callbacks(object):
 
         try:
             if content_dict["m.relates_to"]["rel_type"] == "m.replace":
+                # Get the original message's event ID.
                 edited_event = content_dict["m.relates_to"]["event_id"]
                 edited_content = await self.process_message(
                     content_dict["m.new_content"]["body"], channel_id
                 )
+
+                # Get the corresponding Discord message.
                 webhook_message = message_store[edited_event]
 
                 try:
                     await webhook_message.edit(content=edited_content)
+                # Handle exception if edited message was deleted on Discord.
                 except (
                     discord.errors.NotFound, discord.errors.HTTPException
                 ) as e:
@@ -388,10 +409,13 @@ class Callbacks(object):
         try:
             if content_dict["m.relates_to"]["m.in_reply_to"]["event_id"] in \
                     message_store.values():
+                # Remove the first occurance of our bot's username if replying.
+                # > <@discordbridge:something.org> [discord user]
                 message = message.replace(f"<{config['username']}>", "", 1)
         except KeyError:
             pass
 
+        # _testuser waves_ (Italics)
         if content_dict["msgtype"] == "m.emote":
             message = f"_{author} {message}_"
 
@@ -399,19 +423,22 @@ class Callbacks(object):
 
         embed = None
 
-        # Get attachments
+        # Get attachments.
         try:
             attachment = event.url.split("/")[-1]
+            # TODO: Fix URL for attachments forwarded from other rooms.
             attachment = f"{url}/{homeserver}/{attachment}"
 
             embed = discord.Embed(colour=discord.Colour.blue(), title=message)
             embed.set_image(url=attachment)
 
+            # Send attachment URL in message along with embed,
+            # Just in-case the attachment is not an image.
             message = attachment
         except AttributeError:
             pass
 
-        # Get avatar
+        # Get avatar.
         for user in room.users.values():
             if user.user_id == event.sender:
                 if user.avatar_url:
@@ -427,10 +454,11 @@ class Callbacks(object):
         if self.to_return(room, event):
             return
 
-        # Redact webhook message
+        # Try to fetch the message from cache.
         try:
             message = message_store[event.redacts]
             await message.delete()
+        # Handle exception if message was already deleted on Discord.
         except discord.errors.NotFound as e:
             self.matrix_client.logger.warning(
                 f"Failed to delete message {event.event_id}: {e}"
@@ -443,12 +471,15 @@ class Callbacks(object):
                 or room.room_id not in config["bridge"].values():
             return
 
+        # Return if the event is sent by our bot.
         if len(room.typing_users) == 1 and \
                 self.matrix_client.user in room.typing_users:
             return
 
+        # Get the corresponding Discord channel.
         channel_id = self.get_channel(room)
 
+        # Send typing event.
         async with channel_store[channel_id].typing():
             return
 
@@ -456,20 +487,27 @@ class Callbacks(object):
         mentions = re.findall(r"(^|\s)(@(\w*))", message)
         emotes = re.findall(r":(\w*):", message)
 
+        # Get the guild from channel ID.
         guild = channel_store[channel_id].guild
 
         added_emotes = []
         for emote in emotes:
+            # Don't replace emote names with IDs multiple times.
+            # :emote: becomes <:emote:emote_id>
             if emote not in added_emotes:
                 added_emotes.append(emote)
                 emote_ = discord.utils.get(guild.emojis, name=emote)
                 if emote_:
                     message = message.replace(f":{emote}:", str(emote_))
 
+        # mentions = [('', '@name', 'name'), (' ', '@', '')]
         for mention in mentions:
+            # Don't fetch member if mention is empty.
+            # Single "@" without any name.
             if mention[2]:
                 member = await guild.query_members(query=mention[2])
                 if member:
+                    # Get first result.
                     message = message.replace(mention[1], member[0].mention)
 
         return message
@@ -478,11 +516,15 @@ class Callbacks(object):
 def main():
     logging.basicConfig(level=logging.INFO)
 
+    # Disable everyone and role mentions.
     allowed_mentions = discord.AllowedMentions(everyone=False, roles=False)
+    # Set command prefix for Discord bot.
     command_prefix = config["discord_prefix"]
+    # Intents to fetch members from guild.
     intents = discord.Intents.default()
     intents.members = True
 
+    # Start Discord bot.
     DiscordClient(
         allowed_mentions=allowed_mentions,
         command_prefix=command_prefix, intents=intents