Add basic support for modules and cogs.

twitchio/ext/commands/__init__.py

@@ -2,3 +2,4 @@
 from .core import *
 from .errors import *
 from .cooldowns import *
+from .meta import Cog

twitchio/ext/commands/bot.py

@@ -23,6 +23,7 @@
 """
 
 import asyncio
+import importlib
 import inspect
 import itertools
 import sys
@@ -33,6 +34,7 @@
 from twitchio.websocket import WSConnection
 from .core import *
 from .errors import *
+from .meta import Cog
 from .stringparser import StringParser
 from .utils import _CaseInsensitiveDict
 
@@ -57,9 +59,9 @@ def __init__(self, irc_token: str, *, nick: str, prefix: Union[str, list, tuple]
             self._commands = {}
             self._command_aliases = {}
 
-        self._events = {}
+        self._modules = {}
         self._cogs = {}
-
+        self._events = {}
         self._checks = []
 
         self.__init__commands__()
@@ -250,6 +252,34 @@ async def handle_checks(self, context):
         except Exception as e:
             return e
 
+    def load_module(self, name: str):
+        """Method which loads a module and it's cogs.
+        Parameters
+        ------------
+        name: str
+            The name of the module to load in dot.path format.
+        """
+        if name in self._modules:
+            return
+
+        module = importlib.import_module(name)
+
+        if hasattr(module, 'prepare'):
+            module.prepare(self)
+        else:
+            del module
+            del sys.modules[name]
+            raise ImportError(f'Module <{name}> is missing a prepare method')
+
+        if name not in self._modules:
+            self._modules[name] = module
+
+    def add_cog(self, cog):
+        if not isinstance(cog, Cog):
+            raise InvalidCog('Cogs must derive from "commands.Cog".')
+
+        cog._load_methods(self)
+
     async def global_before_invoke(self, ctx):
         """|coro|
 

twitchio/ext/commands/core.py

@@ -47,6 +47,9 @@ def __init__(self, name: str, func, **attrs):
         self._cooldowns = []
         self._name = name
 
+        self._instance = None
+        self.cog = None
+
         try:
             self._checks.extend(func.__checks__)
         except AttributeError:
@@ -66,8 +69,6 @@ def __init__(self, name: str, func, **attrs):
         self._after_invoke = None
         self.no_global_checks = attrs.get('no_global_checks', False)
 
-        self._instance = None
-
         for key, value in self.params.items():
             if isinstance(value.annotation, str):
                 self.params[key] = value.replace(annotation=eval(value.annotation, func.__globals__))
@@ -156,7 +157,9 @@ def __init__(self, message, **attrs):
         self.prefix = attrs.get('prefix')
 
         self.command = attrs.get('command')
-        self.cog = attrs.get('cog')
+        if self.command:
+            self.cog = self.command.cog
+
         self.args = attrs.get('args')
         self.kwargs = attrs.get('kwargs')
 

twitchio/ext/commands/errors.py

@@ -31,6 +31,10 @@ class InvalidCogMethod(TwitchCommandError):
     pass
 
 
+class InvalidCog(TwitchCommandError):
+    pass
+
+
 class MissingRequiredArgument(TwitchCommandError):
     pass
 

twitchio/ext/commands/meta.py

@@ -1,7 +1,7 @@
 """
 The MIT License (MIT)
 
-Copyright (c) 2017-2019 TwitchIO
+Copyright (c) 2017-2020 TwitchIO
 
 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the "Software"),
@@ -20,4 +20,40 @@
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 DEALINGS IN THE SOFTWARE.
-"""
+"""
+
+import inspect
+from .core import *
+from .errors import *
+
+
+class Cog:
+
+    __valid_slots__ = ('cog_unload', 'cog_check', 'cog_error', )
+
+    def __init_subclass__(cls, *args, **kwargs):
+
+        try:
+            cls.__name__ = cls.name
+        except AttributeError:
+            cls.name = cls.__name__
+
+        for name, mem in inspect.getmembers(cls):
+            if name.startswith(('cog', 'bot')) and name not in cls.__valid_slots__:  # Invalid method prefixes
+                raise InvalidCogMethod(f'The method "{name}" starts with an invalid prefix (cog or bot).')
+
+        cls._events = {}
+        cls._commands = {}
+
+    def _load_methods(self, bot):
+        for name, method in inspect.getmembers(self):
+            if isinstance(method, Command):
+                method._instance = self
+                method.cog = self
+
+                self._commands[name] = method
+                bot.add_command(method)
+
+    @property
+    def commands(self):
+        return self._commands