Welcome to this workshop! We're going to build a Discord bot with discord.py and Python. Let's dive right into it!

Build a Discord Bot

Prerequisites

Python and Pip
A Discord account

Step 1: Create a Bot Account

Make sure you’re logged on to the Discord website.
Navigate to the application page
Click on the “New Application” button.
Give the application a name and click “Create”.
Create a Bot User by navigating to the “Bot” tab and clicking “Add Bot”.
- Click “Yes, do it!” to continue.
If you want others to invite your bot, make sure that Public Bot is ticked. Also, make sure that Require OAuth2 Code Grant is unchecked.
Copy the token using the “Copy” button.
- NOTE: This is not the same thing as the Client Secret on the General Information page
- WARNING: This token is equivalent to your bot's password, so do not share it with anyone.

Step 2: Invite Your Bot

Go to the “OAuth2” tab
Tick the “bot” checkbox under “scopes”
Tick the permissions required for your bot to function under “Bot Permissions”
Now the resulting URL can be used to add your bot to a server. Copy and paste the URL into your browser, choose a server to invite the bot to, and click “Authorize”.

Source: https://discordpy.readthedocs.io/en/latest/discord.html

Step 3: Setup Your Environment

Install or upgrade discord.py: pip3 install -U discord.py
- NOTE: you may need to use a variation of the pip command depending on your platform.
Create a Python file and name it anything, such as coolio_bot.py
Open the file in your favorite code editor

Step 4: Let's Get Coding

Start off by importing the discord.py library:

import discord

client = discord.Client()

# Add event handlers here

client.run('Your token from Step 1')

Listen to the ready event

# Event handlers
@client.event
async def on_ready():
    print('We have logged in as {0.user}'.format(client))

Listen for a new message:

@client.event
async def on_message(message):
    if message.author == client.user:
        return

    if message.content.startswith('$hello'):
        await message.channel.send('Hello!')

Final Bootstrap Code:

import discord

client = discord.Client()

# Event handlers
@client.event
async def on_ready():
    print('We have logged in as {0.user}'.format(client))

@client.event
async def on_message(message):
    if message.author == client.user:
        return

    if message.content.startswith('$hello'):
        await message.channel.send('Hello!')

client.run('Your token from Step 1')

Step 5: Start Hacking

So now that you've got your bot set up, what's next? Well, of course, start building! Take the next 30 minutes and see what you can come up with. Be ready to share your bot's commands with others for them to try out what you make!

Examples

Add a command

Let's say we want to add a new command. Here's what you would do:

@client.event
async def on_message(message):
    if message.author == client.user:
        return

    if message.content.startswith('$hello'):
        await message.channel.send('Hello!')
    elif message.content.startswith('$hola'):
	await message.channel.send('Hola amigo!')

Echo

A simple echo bot:

@client.event
async def on_message(message):
    if message.author == client.user:
        return

    await message.channel.send(message.content)

Send a random picture

When someone sends $pic, send a link to a random picture from https://picsum.photos/. Note: the ? + randrange() is just for making discord fetch a new picture everytime you send the same link.

from random import randrange

...

@client.event
async def on_message(message):
    if message.author == client.user:
        return

    if message.content.startswith('$pic'):
        await message.channel.send('https://picsum.photos/400/400?' + str(randrange(1000)))

FoothillCSClub/discord-bot-workshop