using Subprocess to avoid long-running task from disconnecting discord.py bot?

praw relies on the requests library, which is synchronous meaning that the code is blocking. This can cause your bot to freeze if the blocking code takes too long to execute.

To get around this, a separate thread can be created that handles the blocking code. Below is an example of this. Note how blocking_function will use time.sleep to block for 10 minutes (600 seconds). This should be more than enough to freeze and eventually crash the bot. However, since the function is in it's own thread using run_in_executor, the bot continues to operate as normal.

New versions

import time
import asyncio
from discord.ext import commands
from concurrent.futures import ThreadPoolExecutor

def blocking_function():
    print('entering blocking function')
    time.sleep(600)
    print('sleep has been completed')
    return 'Pong'

client = commands.Bot(command_prefix='!')

@client.event
async def on_ready():
    print('client ready')

@client.command()
async def ping(ctx):
    loop = asyncio.get_event_loop()
    block_return = await loop.run_in_executor(ThreadPoolExecutor(), blocking_function)
    await ctx.send(block_return)

client.run('token')

Older async version

import time
import asyncio
from discord.ext import commands
from concurrent.futures import ThreadPoolExecutor

def blocking_function():
    print('entering blocking function')
    time.sleep(600)
    print('sleep has been completed')
    return 'Pong'

client = commands.Bot(command_prefix='!')

@client.event
async def on_ready():
    print('client ready')

@client.command()
async def ping():
    loop = asyncio.get_event_loop()
    block_return = await loop.run_in_executor(ThreadPoolExecutor(), blocking_function)
    await client.say(block_return)

client.run('token')