def download(url, user_agent='wswp', num_retries=2):
print("Downloading: " + url)
headers = {'User-agent': user_agent}
req = request.Request(url, headers)
try:
html = request.urlopen(req).read()
except request.URLError as e:
print("Download error: " + e.reason)
html = None
if num_retries > 0:
if hasattr(e, 'code') and 500 <= e.code < 600:
return download(url, user_agent, num_retries - 1)
return html
完整的报错信息
Traceback (most recent call last):
File "E:/practice/demo.py", line 64, in <module>
download('http://httpstat.us/500')
File "E:/practice/demo.py", line 14, in download
html = request.urlopen(req).read()
File "E:\python\lib\urllib\request.py", line 223, in urlopen
return opener.open(url, data, timeout)
File "E:\python\lib\urllib\request.py", line 526, in open
response = self._open(req, data)
File "E:\python\lib\urllib\request.py", line 544, in _open
'_open', req)
File "E:\python\lib\urllib\request.py", line 504, in _call_chain
result = func(*args)
File "E:\python\lib\urllib\request.py", line 1346, in http_open
return self.do_open(http.client.HTTPConnection, req)
File "E:\python\lib\urllib\request.py", line 1318, in do_open
encode_chunked=req.has_header('Transfer-encoding'))
File "E:\python\lib\http\client.py", line 1239, in request
self._send_request(method, url, body, headers, encode_chunked)
File "E:\python\lib\http\client.py", line 1285, in _send_request
self.endheaders(body, encode_chunked=encode_chunked)
File "E:\python\lib\http\client.py", line 1234, in endheaders
self._send_output(message_body, encode_chunked=encode_chunked)
File "E:\python\lib\http\client.py", line 1064, in _send_output
+ b'\r\n'
TypeError: can't concat str to bytes
就是request.Request()错误
将
req = request.Request(url, headers)
改为
req = request.Request(url=url,headers=headers)