accord.py

# Discord bot for playing ABC notation music.
#
# ### Installation
# - Get the dependencies: abc2midi, timidity, ffmpeg, and lame.
# - `pip install discord.py`
# - `ACCORD_TOKEN=(your bot token) python3 accord.py`
#
# ### Usage
# In any channel where the bot is, say: $play (abc notation)
# The input may be multiple lines long, and may be in a ```code block```.
# The bot will respond by uploading an mp3 file.

import discord
import os

client = discord.Client()

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

@client.event
async def on_message(message):
    if message.author == client.user:
        return
    if message.content.startswith('$play'):
        lines = message.content[5:].strip(' \n\r\t`').split('\n')
        if not any(l.startswith('M:') for l in lines): lines = ['M:none'] + lines
        if not any(l.startswith('K:') for l in lines): lines = ['K:C major'] + lines
        if not any(l.startswith('X:') for l in lines): lines = ['X:1'] + lines
        with open('input.abc', 'w') as f:
            f.write('\n'.join(lines) + '\n')
        os.system('rm -f output.mid && abc2midi input.abc -o output.mid')
        if not os.path.isfile('output.mid'):
            await message.channel.send("Couldn't convert to MIDI. Check your syntax!")
            return
        if 0 != os.system('timidity output.mid -EFreverb=0 -Ow -o - | ffmpeg -y -hide_banner -loglevel panic -i - -acodec libmp3lame -ab 256k output.mp3'):
            await message.channel.send("Couldn't convert to mp3. Maybe try again.")
            return
        await message.channel.send(file=discord.File('output.mp3'))

client.run(os.environ['ACCORD_TOKEN'])