Some bug fixes

bot/bot.py

@@ -3,7 +3,8 @@
 import socket
 import warnings
 from collections import defaultdict
-from typing import Dict, Optional
+from contextlib import suppress
+from typing import Dict, List, Optional
 
 import aiohttp
 import discord
@@ -70,6 +71,9 @@ def _connect_statsd(self, statsd_url: str, retry_after: int = 2, attempt: int =
                 attempt + 1
             )
 
+        # All tasks that need to block closing until finished
+        self.closing_tasks: List[asyncio.Task] = []
+
     async def cache_filter_list_data(self) -> None:
         """Cache all the data in the FilterList on the site."""
         full_cache = await self.api_client.get('bot/filter-lists')
@@ -145,6 +149,20 @@ def clear(self) -> None:
 
     async def close(self) -> None:
         """Close the Discord connection and the aiohttp session, connector, statsd client, and resolver."""
+        # Done before super().close() to allow tasks finish before the HTTP session closes.
+        for ext in list(self.extensions):
+            with suppress(Exception):
+                self.unload_extension(ext)
+
+        for cog in list(self.cogs):
+            with suppress(Exception):
+                self.remove_cog(cog)
+
+        # Wait until all tasks that have to be completed before bot is closing is done
+        log.trace("Waiting for tasks before closing.")
+        await asyncio.gather(*self.closing_tasks)
+
+        # Now actually do full close of bot
         await super().close()
 
         if self.api_client:

bot/exts/info/reddit.py

@@ -45,7 +45,7 @@ def cog_unload(self) -> None:
         """Stop the loop task and revoke the access token when the cog is unloaded."""
         self.auto_poster_loop.cancel()
         if self.access_token and self.access_token.expires_at > datetime.utcnow():
-            asyncio.create_task(self.revoke_access_token())
+            self.bot.closing_tasks.append(asyncio.create_task(self.revoke_access_token()))
 
     async def init_reddit_ready(self) -> None:
         """Sets the reddit webhook when the cog is loaded."""

bot/exts/moderation/infraction/_scheduler.py

@@ -74,8 +74,21 @@ async def reapply_infraction(
             return
 
         # Allowing mod log since this is a passive action that should be logged.
-        await apply_coro
-        log.info(f"Re-applied {infraction['type']} to user {infraction['user']} upon rejoining.")
+        try:
+            await apply_coro
+        except discord.HTTPException as e:
+            # When user joined and then right after this left again before action completed, this can't apply roles
+            if e.code == 10007 or e.status == 404:
+                log.info(
+                    f"Can't reapply {infraction['type']} to user {infraction['user']} because user left the guild."
+                )
+            else:
+                log.exception(
+                    f"Got unexpected HTTPException (HTTP {e.status}, Discord code {e.code})"
+                    f"when awaiting {infraction['type']} coroutine for {infraction['user']}."
+                )
+        else:
+            log.info(f"Re-applied {infraction['type']} to user {infraction['user']} upon rejoining.")
 
     async def apply_infraction(
         self,
@@ -178,6 +191,10 @@ async def apply_infraction(
                 log_msg = f"Failed to apply {' '.join(infr_type.split('_'))} infraction #{id_} to {user}"
                 if isinstance(e, discord.Forbidden):
                     log.warning(f"{log_msg}: bot lacks permissions.")
+                elif e.code == 10007 or e.status == 404:
+                    log.info(
+                        f"Can't apply {infraction['type']} to user {infraction['user']} because user left from guild."
+                    )
                 else:
                     log.exception(log_msg)
                 failed = True
@@ -352,9 +369,16 @@ async def deactivate_infraction(
             log_text["Failure"] = "The bot lacks permissions to do this (role hierarchy?)"
             log_content = mod_role.mention
         except discord.HTTPException as e:
-            log.exception(f"Failed to deactivate infraction #{id_} ({type_})")
-            log_text["Failure"] = f"HTTPException with status {e.status} and code {e.code}."
-            log_content = mod_role.mention
+            if e.code == 10007 or e.status == 404:
+                log.info(
+                    f"Can't pardon {infraction['type']} for user {infraction['user']} because user left the guild."
+                )
+                log_text["Failure"] = "User left the guild."
+                log_content = mod_role.mention
+            else:
+                log.exception(f"Failed to deactivate infraction #{id_} ({type_})")
+                log_text["Failure"] = f"HTTPException with status {e.status} and code {e.code}."
+                log_content = mod_role.mention
 
         # Check if the user is currently being watched by Big Brother.
         try:

bot/exts/moderation/watchchannels/_watchchannel.py

@@ -342,11 +342,14 @@ def cog_unload(self) -> None:
         """Takes care of unloading the cog and canceling the consumption task."""
         self.log.trace("Unloading the cog")
         if self._consume_task and not self._consume_task.done():
+            def done_callback(task: asyncio.Task) -> None:
+                """Send exception when consuming task have been cancelled."""
+                try:
+                    task.result()
+                except asyncio.CancelledError:
+                    self.log.info(
+                        f"The consume task of {type(self).__name__} was canceled. Messages may be lost."
+                    )
+
+            self._consume_task.add_done_callback(done_callback)
             self._consume_task.cancel()
-            try:
-                self._consume_task.result()
-            except asyncio.CancelledError as e:
-                self.log.exception(
-                    "The consume task was canceled. Messages may be lost.",
-                    exc_info=e
-                )