RuntimeError: There is no current event loop in thread ... DiscordPy MultiThreading

Question

所以我有一个 python 脚本，我想在其中同时运行多个不和谐机器人。这些由数据库（Firebase）中有多少用户定义。我现在要做的是，我为数据库中的每个用户都有一个循环，它将它添加到一个数组中。然后为该数组中的每个用户启动一个脚本：

def main(user):

        client = discord.Client()

        token = db.child("users").child(user).child("token").get().val()
        print(user + ": " + token)

        applicationId = db.child("users").child(user).child("appid").get().val()

        discordId = user

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

        @client.event
        async def on_message(message):
                print(message)
        client.start(token, bot=False)

def testFunction(some_args):
        print(some_args)
        discord_thread = threading.Thread(target=main, args=(some_args,))
        discord_thread.start()

for user in usersArray:
        testFunction(user)

当我启动脚本时，它会一直工作到 client.start 部分。然后我得到每个线程的错误。 错误：

Exception in thread Thread-2:
Traceback (most recent call last):
  File "C:\Users\jonah\AppData\Local\Programs\Python\Python37\lib\threading.py", line 926, in _bootstrap_inner
    self.run()
  File "C:\Users\jonah\AppData\Local\Programs\Python\Python37\lib\threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "discordnotify.py", line 39, in main
    client = discord.Client()
  File "C:\Users\jonah\AppData\Local\Programs\Python\Python37\lib\site-packages\discord\client.py", line 206, in __init__
    self.loop = asyncio.get_event_loop() if loop is None else loop
  File "C:\Users\jonah\AppData\Local\Programs\Python\Python37\lib\asyncio\events.py", line 644, in get_event_loop
    % threading.current_thread().name)
RuntimeError: There is no current event loop in thread 'Thread-2'.

有没有人可以帮助我？快把我逼疯了！

Answer 1

您不想在运行多个不和谐机器人时使用线程。您可以查看here 了解更多信息，但我现在可以为您安排。修复如何启动不和谐机器人将对您有很大帮助。

首先，您必须意识到Client.run 是几个更底层概念的抽象。

有Client.login 登录客户端，然后Client.connect 实际运行处理。这些是协程。

asyncio 提供了将事物放入事件循环的能力，以便它在有时间的时候工作。

类似这样的东西，例如

loop = asyncio.get_event_loop()

async def foo():
  await asyncio.sleep(10)
  loop.close()

loop.create_task(foo())
loop.run_forever()

如果我们想等待另一个协程发生某些事情，asyncio 也通过 asyncio.Event 的同步方式为我们提供了这个功能。您可以将其视为您正在等待的布尔值：

e = asyncio.Event()
loop = asyncio.get_event_loop()

async def foo():
  await e.wait()
  print('we are done waiting...')
  loop.stop()

async def bar():
  await asyncio.sleep(20)
  e.set()

loop.create_task(bar())
loop.create_task(foo())
loop.run_forever() # foo will stop this event loop when 'e' is set to true
loop.close()

使用这个概念，我们可以将其应用于不和谐机器人本身。

import asyncio
import discord
from collections import namedtuple

# First, we must attach an event signalling when the bot has been
# closed to the client itself so we know when to fully close the event loop.

Entry = namedtuple('Entry', 'client event')
entries = [
  Entry(client=discord.Client(), event=asyncio.Event()),
  Entry(client=discord.Client(), event=asyncio.Event())
]

# Then, we should login to all our clients and wrap the connect call
# so it knows when to do the actual full closure

loop = asyncio.get_event_loop()

async def login():
  for e in entries:
    await e.client.login()

async def wrapped_connect(entry):
  try:
    await entry.client.connect()
  except Exception as e:
    await entry.client.close()
    print('We got an exception: ', e.__class__.__name__, e)
    entry.event.set()

# actually check if we should close the event loop:
async def check_close():
  futures = [e.event.wait() for e in entries]
  await asyncio.wait(futures)

# here is when we actually login
loop.run_until_complete(login())

# now we connect to every client
for entry in entries:
  loop.create_task(wrapped_connect(entry))

# now we're waiting for all the clients to close
loop.run_until_complete(check_close())

# finally, we close the event loop
loop.close()