Cogs

There comes a point in your bot’s development when you want to organize a collection of commands, listeners, and some state into one class. Cogs allow you to do just that.

The gist:

• Each cog is a Python class Cog.

• Every command is marked with the cog.command() decorator.

• Every listener is marked with the cog.listener() decorator.

• Cogs are then registered with the Bot.add_cog() call.

Quick Example

This example cog defines a Greetings category for your commands, with a single command named hello as well as a listener to listen to an Event.

from tg_botting.cog import Cog, command, lisener

class Greetings(Cog):
    def __init__(self, bot):
        self.bot = bot
        self._last_user = None

    @listener()
    async def on_new_member(self, message):
        user = message.new_chat_member
        # or user = message.new_chat_participant
        # I recommend using user = message.new_chat_member or message.new_chat_participant
        await message.send('Welcome {}!'.format(user.first_name))

    @command('hello')
    async def hello(self, message):
        """Says hello"""
        user_id = message.user.id
        # if you need, you can try to load user by pyrogram who has in tg-botting
        # user = await User.load(user_id)
        if self._last_user is None or self._last_user != user_id:
            await message.send('Hello {}!'.format(user.first_name))
        else:
            await message.send('Hello {}... This feels familiar.'.format(user.first_name))
        self._last_user = user_id

A couple of technical notes to take into consideration:

• All commands must now take a self parameter to allow usage of instance attributes that can be used to maintain state.

Cog Registration

Once you have defined your cogs, you need to tell the bot to register the cogs to be used. We do this via the add_cog() method.

bot.add_cog(Greetings(bot))

This binds the cog to the bot, adding all commands and listeners to the bot automatically.

Inspection

Since cogs ultimately are classes, we have some tools to help us inspect certain properties of the cog.

To get a list of commands, we can refer to dict inside the Bot class

>>> commands = bot.all_commands().get(cog_class_name)
>>> print([c.name for c in commands])