Discord Bot在线但不响应消息的问题排查与解决

问题场景 #

我为Discord服务器制作了一个用于内部玩笑的Bot，核心功能是读取消息最后一个单词的末尾两个字母，若以er结尾，则回复{last_word}, I hardly know her!。Bot启动无报错，在Repl.it及测试Discord服务器中均显示在线状态，但完全不响应任何消息。

初始代码如下：

import discord

client = discord.Client(intents=discord.Intents.default())

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

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

    words = message.content.split()
    last_word = words[-1].lower() if words else ""

    if last_word.endswith("er"):
        response = f"{last_word} I hard know her"
        await message.channel.send(response) 

    # Continue processing other commands
    await client.process_commands(message)

client.run('Token')

初步排查 #

首先怀疑是消息权限问题，于是修改代码开启message_content意图，同时在Discord开发者平台勾选了对应的权限选项：

import discord

intents = discord.Intents.default()
intents.message_content = True

client = discord.Client(intents=intents)

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

async def on_message(message):

    if message.author == client.user:
        return

    words = message.content.split()
    last_word = words[-1].lower() if words else ""

    if last_word.endswith("er"):
        response = f"{last_word} I hard know her"
        await message.channel.send(response) 

    # Continue processing other commands
    await client.process_commands(message)

client.run('Token')

但修改后问题依旧存在。

最终解决 #

经过检查，发现问题根源是on_message函数没有添加@client.event装饰器——Discord.py需要通过这个装饰器来识别消息事件的处理函数。添加装饰器后，Bot正常响应消息，同时我还扩展了检测逻辑，新增对or/ar结尾单词的支持，最终正确代码如下：

import discord

intents = discord.Intents.default()
intents.message_content = True

client = discord.Client(intents=intents)

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

@client.event  # 添加此装饰器将函数注册为消息事件处理器
async def on_message(message):
    if message.author == client.user:
        return

    words = message.content.split()
    last_word = words[-1].lower() if words else ""

    if last_word.endswith("er") or last_word.endswith("or") or last_word.endswith("ar"):
        response = f"{last_word}, I hardly know her!"
        await message.channel.send(response)

    # 继续处理其他命令
    await client.process_commands(message)


client.run('Token')

内容的提问来源于stack exchange，提问作者Phighlow