added db functions and join/leave vc

cogs/music/util.py

@@ -0,0 +1,47 @@
+import discord
+from discord.ext import commands
+from discord.ext.commands.context import Context
+from discord.ext.commands.converter import CommandError
+
+
+# Joining/moving to the user's vc in a guild
+async def join_vc(ctx: Context):
+
+    # Get the user's vc
+    author_voice = getattr(ctx.author, "voice")
+    if author_voice is None:
+        # Raise exception if user is not in vc
+        raise CommandError("User is not in voice channel")
+
+    # Get user's vc
+    vc = getattr(author_voice, "channel")
+    if vc is None:
+        raise CommandError("Unable to find voice channel")
+
+    # Join or move to the user's vc
+    if ctx.voice_client is None:
+        await vc.connect()
+    else:
+        # Safe to ignore type error for now
+        await ctx.voice_client.move_to(vc)
+
+
+# Leaving the voice channel of a user
+async def leave_vc(ctx: Context):
+    # If the bot is not in a vc of this server
+    if ctx.voice_client is None:
+        raise CommandError("I am not in a voice channel")
+
+    # if user is not in voice of the server
+    author_voice = getattr(ctx.author, "voice")
+    if author_voice is None:
+        raise CommandError("You are not in a voice channel")
+
+    # Make sure both bot and User are in same vc
+    vc = ctx.voice_client.channel
+    author_vc = getattr(author_voice, "channel")
+    if author_vc is None or vc != author_vc:
+        raise CommandError("You are not in this voice channel")
+
+    # Disconnect
+    await ctx.voice_client.disconnect(force=False)