Telethon Bot向私有频道发消息被识别为PeerUser的问题求助

问题描述 #

尝试用Telethon框架的Bot向私有频道My_channel发送消息时，系统将频道名称识别为PeerUser，触发如下错误：

Traceback (most recent call last):
  File "/app/telegram_send_msg.py", line 92, in <module>
    main()
  File "/app/telegram_send_msg.py", line 81, in main
    tg.send_message(message["receiver"], message["message"], mark_as_read=profile["name"] == "duchenpaul")
  File "/app/telegram_send_msg.py", line 56, in send_message
    self.client.send_message(entity = receiver, message = message)
  File "/usr/local/lib/python3.11/site-packages/telethon/sync.py", line 39, in syncified
    return loop.run_until_complete(coro)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/asyncio/base_events.py", line 653, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/telethon/client/messages.py", line 838, in send_message
    entity = await self.get_input_entity(entity)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/telethon/client/users.py", line 461, in get_input_entity
    raise ValueError(
ValueError: Could not find the input entity for PeerUser(user_id=1909685838) (PeerUser). Please read https://docs.telethon.dev/en/stable/concepts/entities.html to find out more details.

相关代码实现：

import os
import logging
import time
from telethon import TelegramClient

class Telegram(object):
    """Telegram Class"""

    def __init__(self, name: str, api_id: int, api_hash: str, config_path: str, bot_token=''):
        self.name = name
        self.session = os.path.join(config_path, f'{self.name}.session')
        self.api_id = api_id
        self.api_hash = api_hash
        self.bot_token = bot_token if bot_token else None
        logging.info(f"Telegram: Start session: {self.name}")
        self.client = TelegramClient(self.session, self.api_id, self.api_hash)
        self.client.start(bot_token=self.bot_token)

    def send_message(self, receiver, message, mark_as_read=False):
        """Send telegram message

        Args:
            receiver (str): the reciever's accout, i.e. @someone
            message (str): The message to send
            mark_as_read (bool, optional): If mark reciever's message as read. Defaults to False.
        """
        logging.info(f"Telegram: Sending \"{message}\" to {receiver}.")
        self.client.send_message(entity = receiver, message = message)
        if mark_as_read:
            logging.info(f"Telegram: Mark {receiver}'s message as read.")
            time.sleep(2)
            self.client.send_read_acknowledge(receiver)

    def get_joined_channel(self):
        for dialog in self.client.iter_dialogs():
            channelId = dialog.entity.id
            channelName = dialog.name

    def disconnect(self):
        logging.info(f"Disconnect session: {self.name}")
        self.client.disconnect()

# 假设profile和message是已定义的配置
tg = Telegram(profile["name"], profile["api_id"], profile["api_hash"], config["config_dir"], profile.get("bot_token"))
tg.send_message(message["receiver"], message["message"])

问题核心：私有频道信息未被会话缓存记录，且Bot无法通过iter_dialogs获取私有频道实体。

解决方法 #

1. 手动构造私有频道的InputChannel实体 #

私有频道名称无法被Telethon直接解析，必须通过频道ID和access_hash定位：

• 先用普通用户账号（非Bot）运行以下代码获取频道的ID和access_hash：

  from telethon import TelegramClient
  
  client = TelegramClient("user_session", YOUR_API_ID, YOUR_API_HASH)
  client.start()
  
  # 替换为私有频道的用户名（@xxx）
  entity = client.get_entity("@My_channel")
  print(f"频道ID: {entity.id}")
  print(f"Access Hash: {entity.access_hash}")
  client.disconnect()
  

• 在Bot代码中，手动构造InputChannel实体并传入send_message：
  修改Telegram类，添加专属方法或直接使用构造好的实体：

  from telethon.tl.types import InputChannel
  
  # 在Telegram类中添加方法
  def send_to_private_channel(self, channel_id, access_hash, message):
      channel_entity = InputChannel(channel_id=channel_id, access_hash=access_hash)
      self.client.send_message(entity=channel_entity, message=message)
  
  # 调用示例
  tg.send_to_private_channel(123456789, 9876543210987654321, "测试消息")
  

2. 确保Bot已加入私有频道 #

• 先将Bot账号添加为私有频道的成员（管理员或普通成员均可）
• 添加后，可尝试用Bot客户端调用get_entity传入频道邀请链接获取实体：

  # 替换为私有频道的邀请链接
  entity = await self.client.get_entity("https://t.me/joinchat/ABC123XYZ")
  self.client.send_message(entity=entity, message="测试消息")
  

3. 优化实体处理逻辑 #

避免直接使用字符串作为send_message的entity参数，优先使用明确的实体对象（如InputChannel），减少Telethon自动解析的出错概率。

内容的提问来源于stack exchange，提问作者Chen Du