SSLError (Read operation timed out) in Python requests

Question

I have a python API script and my script sometimes gets terminated on this line despite using try/except . Here is the code:

    try:
            r = requests.post(URL, data=params, headers=headers, timeout=self.request_timeout)
            try:
                response = r.json()
            except Exception, e:
                message = "ERROR_0104! Unexpected error occured. The error is: "
                message += str(e)
                print message
                aux_func.write_log(message)
                return 'Switch'
    except requests.exceptions.RequestException:
            print "Exception occurred on 'API requests post' procedure."
            counter += 1
            continue
    ...

The error occurs on the second line of above shown code. This is the error:

     r = requests.post(URL, data=params, headers=headers, timeout=self.request_timeout)
      File "/usr/local/lib/python2.7/dist-packages/requests/api.py", line 88, in post
        return request('post', url, data=data, **kwargs)
      File "/usr/local/lib/python2.7/dist-packages/requests/api.py", line 44, in request
        return session.request(method=method, url=url, **kwargs)
      File "/usr/local/lib/python2.7/dist-packages/requests/sessions.py", line 383, in request
        resp = self.send(prep, **send_kwargs)
      File "/usr/local/lib/python2.7/dist-packages/requests/sessions.py", line 486, in send
        r = adapter.send(request, **kwargs)
      File "/usr/local/lib/python2.7/dist-packages/requests/adapters.py", line 394, in send
        r.content
      File "/usr/local/lib/python2.7/dist-packages/requests/models.py", line 679, in content
        self._content = bytes().join(self.iter_content(CONTENT_CHUNK_SIZE)) or bytes()
      File "/usr/local/lib/python2.7/dist-packages/requests/models.py", line 616, in generate
        decode_content=True):
      File "/usr/local/lib/python2.7/dist-packages/requests/packages/urllib3/response.py", line 236, in stream
        data = self.read(amt=amt, decode_content=decode_content)
      File "/usr/local/lib/python2.7/dist-packages/requests/packages/urllib3/response.py", line 183, in read
        data = self._fp.read(amt)
      File "/usr/lib/python2.7/httplib.py", line 543, in read
        return self._read_chunked(amt)
      File "/usr/lib/python2.7/httplib.py", line 585, in _read_chunked
        line = self.fp.readline(_MAXLINE + 1)
      File "/usr/lib/python2.7/socket.py", line 476, in readline
        data = self._sock.recv(self._rbufsize)
      File "/usr/lib/python2.7/ssl.py", line 305, in recv
        return self.read(buflen)
      File "/usr/lib/python2.7/ssl.py", line 224, in read
        return self._sslobj.read(len)
    ssl.SSLError: The read operation timed out

I presume something within the Requests module is causing this, but I don't know what.

Answer 1

The read operation has timed out, as it says.

It times out, however, with an ssl.SSLError . This is not what your except is catching. If you want to catch and retry, you need to catch the right error.

Answer 2

I saw that there was some confusion here regarding what the solution is because of lack of enough details. I posted the answer on the comment to the top post but the formatting is not great in the comment section and I will post a properly formatted answer here.

The problem, as Veedrac has mentioned is that I was not catching all the possible exceptions in the code that I posted in the question. My code only catches "requests.exceptions.RequestException", and any other exception will cause the code to exit abruptly.

Instead, I'm gonna re-write the code like this:

try:
        r = requests.post(URL, data=params, headers=headers, timeout=self.request_timeout)
        try:
            response = r.json()
        except Exception, e:
            message = "ERROR_0104! Unexpected error occured. The error is: "
            message += str(e)
            print message
            aux_func.write_log(message)
            return 'Switch'
except requests.exceptions.RequestException:
        print "Exception occurred on 'API requests post' procedure."
        counter += 1
        continue
except Exception, e:
        print "Exception {0} occurred".format(e)
        continue

All I did was add an extra generic exception catcher at the end which will catch all other unaccounted for exceptions.

I hope this helps.

Thanks.

Answer 3

except Exception, e不适用于> = Python 3 except Exception as e你必须使用它