python - 当我使用 urllib2 时回溯，收到 HTTP 500 错误

Question

我的代码如下，但运行时会抛出错误。

search_request = urllib2.Request(url,data=tmp_file_name,headers={'X-Requested-With':'WoMenShi888XMLHttpRequestWin'})
#print search_request.get_method()
search_response = urllib2.urlopen(search_request)
html_data = search_response.read()

错误是:

Traceback (most recent call last):
  File "xx_tmp.py", line 83, in <module>
    print hello_lfi()
  File "xx_tmp.py", line 69, in hello_lfi
    search_response = urllib2.urlopen(search_request)
  File "D:\Python27\lib\urllib2.py", line 126, in urlopen
    return _opener.open(url, data, timeout)
  File "D:\Python27\lib\urllib2.py", line 406, in open
    response = meth(req, response)
  File "D:\Python27\lib\urllib2.py", line 519, in http_response
    'http', request, response, code, msg, hdrs)
  File "D:\Python27\lib\urllib2.py", line 444, in error
    return self._call_chain(*args)
  File "D:\Python27\lib\urllib2.py", line 378, in _call_chain
    result = func(*args)
  File "D:\Python27\lib\urllib2.py", line 527, in http_error_defau
    raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
urllib2.HTTPError: HTTP Error 500: Internal Server Error

不知道怎么解决？我的意思是，当发生错误时，我的代码如何继续工作？

当我尝试使用时

       try:
                search_response = urllib2.urlopen(search_request)
            except urllib2.HTTPError:
                pass

新错误

UnboundLocalError: local variable 'search_response' referenced before assignment

我用

global search_response

并且有错误

NameError: global name 'search_response' is not defined

Answer 1

您可以捕获异常，这将防止您的程序“突然”停止:

try:
  search_response = urllib2.urlopen(search_request)
except urllib2.HTTPError:
  print 'There was an error with the request'

如果您想继续，您可以简单地:

try:
  search_response = urllib2.urlopen(search_request)
except urllib2.HTTPError:
  pass

这将使您的程序能够继续；但您的其他语句 html_data = search_response.read() 不会给您预期的结果。要永久解决此问题，您需要调试您的请求以查看失败的原因；这不是 Python 特有的东西。