使用Pytube下载YouTube视频遇RegexMatchError问题求助

问题详情 #

环境：Python 3.9.9、Pytube 15.0.0

使用以下代码下载YouTube视频时出现错误：

from pytube import YouTube

video = YouTube('https://www.youtube.com/watch?v=AWXvSBHB210')
video.streams.get_highest_resolution().download()

错误信息（翻译后） #

Traceback (most recent call last):
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\__main__.py", line 181, in fmt_streams
    extract.apply_signature(stream_manifest, self.vid_info, self.js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\extract.py", line 409, in apply_signature
    cipher = Cipher(js=js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 43, in __init__
    self.throttling_plan = get_throttling_plan(js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 405, in get_throttling_plan
    raw_code = get_throttling_function_code(js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 311, in get_throttling_function_code
    name = re.escape(get_throttling_function_name(js))
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 296, in get_throttling_function_name
    raise RegexMatchError(
pytube.exceptions.RegexMatchError: get_throttling_function_name: 无法匹配到对应的函数名

在处理上述异常期间，又触发了新的异常：

Traceback (most recent call last):
  文件 "c:\Users\Tobias\Desktop\Exal\test01.py", line 4, in <module>
    video.streams.get_highest_resolution().download()
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\__main__.py", line 296, in streams
    return StreamQuery(self.fmt_streams)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\__main__.py", line 188, in fmt_streams
    extract.apply_signature(stream_manifest, self.vid_info, self.js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\extract.py", line 409, in apply_signature
    cipher = Cipher(js=js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 43, in __init__
    self.throttling_plan = get_throttling_plan(js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 405, in get_throttling_plan
    raw_code = get_throttling_function_code(js)
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 311, in get_throttling_function_code
    name = re.escape(get_throttling_function_name(js))
  文件 "C:\Users\Tobias\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py", line 296, in get_throttling_function_name
    raise RegexMatchError(
pytube.exceptions.RegexMatchError: get_throttling_function_name: 无法匹配到对应的函数名

解决方案 #

1. 升级Pytube到最新版本 #

YouTube会频繁更新页面逻辑，旧版本Pytube的正则规则无法适配。执行以下命令升级：

pip install --upgrade pytube

2. 手动修改cipher.py的正则匹配规则 #

如果升级后问题仍存在，找到Pytube安装目录下的cipher.py文件（路径示例：C:\Users\你的用户名\AppData\Roaming\Python\Python39\site-packages\pytube\cipher.py），替换get_throttling_function_name函数为：

def get_throttling_function_name(js: str) -> str:
    pattern = r'a\.[a-zA-Z]\s*&&\s*\([a-z]\s*=\s*a\.get\("n"\)\)\s*&&\s*' \
              r'\([a-z]\s*=\s*([a-zA-Z0-9$]+)(\[\d+\])?\([a-z]\)'
    match = re.search(pattern, js)
    if not match:
        pattern = r'\([a-z]\s*=\s*([a-zA-Z0-9$]+)(\[\d+\])?\([a-z]\)'
        match = re.search(pattern, js)
    if not match:
        raise RegexMatchError(
            caller="get_throttling_function_name", pattern=pattern
        )
    return match.group(1)

3. 改用Pytube的维护fork版本 #

官方Pytube更新不及时时，可以使用社区维护的pytubefix：

pip install pytubefix

修改代码为：

from pytubefix import YouTube

video = YouTube('https://www.youtube.com/watch?v=AWXvSBHB210')
video.streams.get_highest_resolution().download()

内容的提问来源于stack exchange，提问作者Wolfie WS