Use a defaultdict(list) for filter_list_cache.

3 files changed, 7 insertions, 6 deletions

diff --git a/bot/bot.py b/bot/bot.py
index 3dfb4e948..a309e7192 100644
--- a/bot/bot.py
+++ b/bot/bot.py
@@ -2,6 +2,7 @@ import asyncio
 import logging
 import socket
 import warnings
+from collections import defaultdict
 from typing import Optional
 
 import aiohttp
@@ -34,7 +35,7 @@ class Bot(commands.Bot):
         self.redis_ready = asyncio.Event()
         self.redis_closed = False
         self.api_client = api.APIClient(loop=self.loop)
-        self.filter_list_cache = {}
+        self.filter_list_cache = defaultdict(list)
 
         self._connector = None
         self._resolver = None
@@ -64,7 +65,7 @@ class Bot(commands.Bot):
                 "created_at": item.get("created_at"),
                 "updated_at": item.get("updated_at"),
             }
-            self.filter_list_cache.setdefault(f"{type_}.{allowed}", []).append(metadata)
+            self.filter_list_cache[f"{type_}.{allowed}"].append(metadata)
 
     async def _create_redis_session(self) -> None:
         """
diff --git a/bot/cogs/filter_lists.py b/bot/cogs/filter_lists.py
index 9bd2da330..63d74e421 100644
--- a/bot/cogs/filter_lists.py
+++ b/bot/cogs/filter_lists.py
@@ -88,7 +88,7 @@ class FilterLists(Cog):
             "created_at": item.get("created_at"),
             "updated_at": item.get("updated_at"),
         }
-        self.bot.filter_list_cache.setdefault(f"{type_}.{allowed}", []).append(metadata)
+        self.bot.filter_list_cache[f"{type_}.{allowed}"].append(metadata)
         await ctx.message.add_reaction("✅")
 
     async def _delete_data(self, ctx: Context, allowed: bool, list_type: ValidFilterListType, content: str) -> None:
@@ -110,7 +110,7 @@ class FilterLists(Cog):
 
         # Find the content and delete it.
         log.trace(f"Trying to delete the {content} item from the {list_type} {allow_type}")
-        for allow_list in self.bot.filter_list_cache.get(f"{list_type}.{allowed}", []):
+        for allow_list in self.bot.filter_list_cache[f"{list_type}.{allowed}"]:
             if content == allow_list.get("content"):
                 item = allow_list
                 break
@@ -125,7 +125,7 @@ class FilterLists(Cog):
     async def _list_all_data(self, ctx: Context, allowed: bool, list_type: ValidFilterListType) -> None:
         """Paginate and display all items in a filterlist."""
         allow_type = "whitelist" if allowed else "blacklist"
-        result = self.bot.filter_list_cache.get(f"{list_type}.{allowed}", [])
+        result = self.bot.filter_list_cache[f"{list_type}.{allowed}"]
 
         # Build a list of lines we want to show in the paginator
         lines = []
diff --git a/bot/cogs/filtering.py b/bot/cogs/filtering.py
index 652af5ff5..9f9bcc464 100644
--- a/bot/cogs/filtering.py
+++ b/bot/cogs/filtering.py
@@ -101,7 +101,7 @@ class Filtering(Cog):
 
     def _get_filterlist_items(self, list_type: str, *, allowed: bool, compiled: Optional[bool] = False) -> list:
         """Fetch items from the filter_list_cache."""
-        items = self.bot.filter_list_cache.get(f"{list_type.upper()}.{allowed}", [])
+        items = self.bot.filter_list_cache[f"{list_type.upper()}.{allowed}"]
 
         if compiled:
             return [re.compile(fr'{item["content"]}', flags=re.IGNORECASE) for item in items]