urllib 请求给出 404 错误，但在浏览器中工作正常

Question

当我尝试这条线时：

import urllib.request

urllib.request.urlretrieve("https://i.redd.it/53tfh959wnv41.jpg", "photo.jpg")

我收到以下错误：

Traceback (most recent call last):
  File "scraper.py", line 26, in <module>
    urllib.request.urlretrieve("https://i.redd.it/53tfh959wnv41.jpg", "photo.jpg")
  File "/usr/lib/python3.6/urllib/request.py", line 248, in urlretrieve 
    with contextlib.closing(urlopen(url, data)) as fp:
  File "/usr/lib/python3.6/urllib/request.py", line 223, in urlopen
    return opener.open(url, data, timeout)
  File "/usr/lib/python3.6/urllib/request.py", line 532, in open
    response = meth(req, response)
  File "/usr/lib/python3.6/urllib/request.py", line 642, in http_response
    'http', request, response, code, msg, hdrs)
  File "/usr/lib/python3.6/urllib/request.py", line 570, in error
    return self._call_chain(*args)
  File "/usr/lib/python3.6/urllib/request.py", line 504, in _call_chain
    result = func(*args)
  File "/usr/lib/python3.6/urllib/request.py", line 650, in http_error_default
    raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 404: Not Found

但是该链接在我的浏览器中可以正常工作吗？为什么它在浏览器中有效，但对请求无效？它适用于同一网站的其他图片。

Answer 1

请求返回

如果您检查您的开发者控制台，它是 404：

所以你看到的是 imgur 的自定义 404“页面”（这是一个图像）。

编辑：

所以urlretrieve 在 404 状态码上失败。如果你想使用请求的内容（即使状态码是 404）你可以这样做：

try:
    urllib.request.urlretrieve("https://i.redd.it/53tfh959wnv41.jpg", "photo.jpg")
except Exception as e:
    with open("error_photo.jpg", 'wb') as fp:
        fp.write(e.read())

Answer 2

尝试更改用户代理。你可以只添加一个 kwarg：

req = urllib.request.urlretrieve("https://i.redd.it/53tfh959wnv41.jpg", "photo.jpg", headers={"User-Agent": "put custom user agent here"})