制作Discord机器人遇TypeError：Token为NoneType问题求助

作为编程新手，制作Discord机器人时持续遇到以下报错：

Traceback (most recent call last):
File "c:\Users\bhati\Desktop\molectron\app.py", line 107, in
bot.run(DISCORD_TOKEN)
File "C:\Users\bhati\AppData\Local\Programs\Python\Python39\lib\site-packages\discord\client.py", line 860, in run
asyncio.run(runner())
File "C:\Users\bhati\AppData\Local\Programs\Python\Python39\lib\asyncio\runners.py", line 44, in run
return loop.run_until_complete(main)
File "C:\Users\bhati\AppData\Local\Programs\Python\Python39\lib\asyncio\base_events.py", line 642, in run_until_complete
return future.result()
File "C:\Users\bhati\AppData\Local\Programs\Python\Python39\lib\site-packages\discord\client.py", line 849, in runner
await self.start(token, reconnect=reconnect)
File "C:\Users\bhati\AppData\Local\Programs\Python\Python39\lib\site-packages\discord\client.py", line 777, in start
await self.login(token)
File "C:\Users\bhati\AppData\Local\Programs\Python\Python39\lib\site-packages\discord\client.py", line 609, in login
raise TypeError(f'expected token to be a str, received {token.class.name} instead')
TypeError: expected token to be a str, received NoneType instead

我的代码如下：

import discord
from discord.ext import commands,tasks
import os
from dotenv import load_dotenv
import youtube_dl
import asyncio
load_dotenv()

# Get the API token from the .env file.
DISCORD_TOKEN = os.getenv("discord_token")
print(DISCORD_TOKEN)

intents = discord.Intents().all()
client = discord.Client(intents=intents)
bot = commands.Bot(command_prefix='!',intents=intents)
youtube_dl.utils.bug_reports_message = lambda: ''

ytdl_format_options = {
    'format': 'bestaudio/best',
    'restrictfilenames': True,
    'noplaylist': True,
    'nocheckcertificate': True,
    'ignoreerrors': False,
    'logtostderr': False,
    'quiet': True,
    'no_warnings': True,
    'default_search': 'auto',
    'source_address': '0.0.0.0' # bind to ipv4 since ipv6 addresses cause issues sometimes
}

ffmpeg_options = {
    'options': '-vn'
}

ytdl = youtube_dl.YoutubeDL(ytdl_format_options)

class YTDLSource(discord.PCMVolumeTransformer):
    def __init__(self, source, *, data, volume=0.5):
        super().__init__(source, volume)
        self.data = data
        self.title = data.get('title')
        self.url = ""

    @classmethod
    async def from_url(cls, url, *, loop=None, stream=False):
        loop = loop or asyncio.get_event_loop()
        data = await loop.run_in_executor(None, lambda: ytdl.extract_info(url, download=not stream))
        if 'entries' in data:
            # take first item from a playlist
            data = data['entries'][0]
        filename = data['title'] if stream else ytdl.prepare_filename(data)
        return filename
@bot.command(name='join', help='Tells the bot to join the voice channel')
async def join(ctx):
    if not ctx.message.author.voice:
        await ctx.send("{} is not connected to a voice channel".format(ctx.message.author.name))
        return
    else:
        channel = ctx.message.author.voice.channel
    await channel.connect()

@bot.command(name='leave', help='To make the bot leave the voice channel')
async def leave(ctx):
    voice_client = ctx.message.guild.voice_client
    if voice_client.is_connected():
        await voice_client.disconnect()
    else:
        await ctx.send("The bot is not connected to a voice channel.")
@bot.command(name='play_song', help='To play song')
async def play(ctx,url):
    try :
        server = ctx.message.guild
        voice_channel = server.voice_client

        async with ctx.typing():
            filename = await YTDLSource.from_url(url, loop=bot.loop)
            voice_channel.play(discord.FFmpegPCMAudio(executable="ffmpeg.exe", source=filename))
        await ctx.send('**Now playing:** {}'.format(filename))
    except:
        await ctx.send("The bot is not connected to a voice channel.")


@bot.command(name='pause', help='This command pauses the song')
async def pause(ctx):
    voice_client = ctx.message.guild.voice_client
    if voice_client.is_playing():
        await voice_client.pause()
    else:
        await ctx.send("The bot is not playing anything at the moment.")
    
@bot.command(name='resume', help='Resumes the song')
async def resume(ctx):
    voice_client = ctx.message.guild.voice_client
    if voice_client.is_paused():
        await voice_client.resume()
    else:
        await ctx.send("The bot was not playing anything before this. Use play_song command")

@bot.command(name='stop', help='Stops the song')
async def stop(ctx):
    voice_client = ctx.message.guild.voice_client
    if voice_client.is_playing():
        await voice_client.stop()
    else:
        await ctx.send("The bot is not playing anything at the moment.")
if __name__ == "__main__" :
    bot.run(DISCORD_TOKEN)

我已经查阅相关指南和文档，重装了所有模块，但都没解决问题。原本期望机器人能上线并响应命令，但未能实现。

解决方法 #

这个报错的核心原因是DISCORD_TOKEN变量的值为None，也就是程序没从.env文件里正确读取到机器人令牌。按以下步骤排查：

1. 检查.env文件的位置和内容

   • .env文件必须和你的app.py放在同一个文件夹里
   • .env文件里的键名要和代码里完全一致，代码里用的是discord_token，所以.env里要写：discord_token=你的机器人令牌字符串，注意不要给令牌加引号，也不要在=前后加空格

2. 指定load_dotenv的路径（可选）
   如果你的.env文件不在当前工作目录，可以手动指定路径：

   load_dotenv(dotenv_path='./.env')  # 这里填.env的实际路径
   

3. 验证环境变量是否加载成功
   在print(DISCORD_TOKEN)后面加一行代码，打印所有环境变量，确认discord_token存在：

   print(os.environ.get("discord_token"))
   

   如果还是None，说明.env文件没被正确读取，检查文件路径和拼写。

4. 代码优化（额外建议）
   你的代码里同时创建了client = discord.Client(intents=intents)和bot = commands.Bot(...)，实际上只需要bot就足够了，删掉client的定义，避免不必要的资源占用。

内容的提问来源于stack exchange，提问作者Moulik Bhatia