Implement basic custom prefixes

Author: No767

bot/libs/utils/prefix.py

@@ -0,0 +1,47 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Union
+
+import discord
+from async_lru import alru_cache
+
+if TYPE_CHECKING:
+    from bot.rodhaj import Rodhaj
+
+
+@alru_cache(maxsize=1024)
+async def get_prefix(bot: Rodhaj, message: discord.Message) -> Union[str, list[str]]:
+    """Obtains the prefix for the guild
+
+    This coroutine is heavily cached in order to reduce database calls
+    and improved performance
+
+
+    Args:
+        bot (Rodhaj): An instance of `Rodhaj`
+        message (discord.Message): The message that is processed
+
+    Returns:
+        Union[str, List[str]]: The default prefix or
+        a list of prefixes (including the default)
+    """
+    user_id = bot.user.id  # type: ignore
+
+    # By putting the base with the mentions, we are effectively
+    # doing the exact same thing as commands.when_mentioned
+    base = [f"<@!{user_id}> ", f"<@{user_id}> ", bot.default_prefix]
+    if message.guild is None:
+        get_prefix.cache_invalidate(bot, message)
+        return base
+
+    query = """
+    SELECT prefix
+    FROM guild_config
+    WHERE id = $1;
+    """
+    prefixes = await bot.pool.fetchval(query, message.guild.id)
+    if prefixes is None:
+        get_prefix.cache_invalidate(bot, message)
+        return base
+    base.extend(item for item in prefixes)
+    return base

bot/rodhaj.py

@@ -19,11 +19,13 @@
     RodhajHelp,
     send_error_embed,
 )
+from libs.utils.prefix import get_prefix
 from libs.utils.reloader import Reloader
 
 if TYPE_CHECKING:
     from cogs.tickets import Tickets
 
+
 TRANSPROGRAMMER_GUILD_ID = 1183302385020436480
 
 
@@ -46,13 +48,14 @@ def __init__(
             allowed_mentions=discord.AllowedMentions(
                 everyone=False, replied_user=False
             ),
-            command_prefix=["r>", "?", "!"],
+            command_prefix=get_prefix,
             help_command=RodhajHelp(),
             intents=intents,
             tree_cls=RodhajCommandTree,
             *args,
             **kwargs,
         )
+        self.default_prefix = "r>"
         self.logger = logging.getLogger("rodhaj")
         self.session = session
         self.partial_config: Optional[PartialConfig] = None