TypeError: getresponse() got an unexpected keyword argument 'buffering'         

Firstly, please note I have already read issues #1289 and  #1915.

Secondly, please note that I am fully aware that the problem is that the underlying URL fetch failed due to a problem that is outside Requests' control, i.e. a network problem or failure of the remote web server.

My problem is not that an exception is raised - my problem is that the _wrong_ exception is raised. According to the Requests documentation, in this circumstance a `ReadTimeout` exception should be raised, and in any event the exception should be a subclass of `RequestException`. Instead, a `TypeError` is being raised. This is fatal for my application, which needs to know _why_ the request failed and to be sure that it was indeed a network failure and not a bug in the application or Requests itself. As far as I can see, this is indeed a bug in Requests.

 I am using Requests 2.5.3 on Python 3.4.0 on Ubuntu 14.04.2.

```
Traceback (most recent call last):                                                                                                                                                   
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 372, in _make_request                                             
    httplib_response = conn.getresponse(buffering=True)                                                                                                                              
TypeError: getresponse() got an unexpected keyword argument 'buffering'                                                                                                              

During handling of the above exception, another exception occurred:                                                                                                                  

Traceback (most recent call last):                                                                                                                                                   
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 374, in _make_request                                             
    httplib_response = conn.getresponse()                                                                                                                                            
  File "/usr/lib/python3.4/http/client.py", line 1147, in getresponse                                                                                                                
    response.begin()                                                                                                                                                                 
  File "/usr/lib/python3.4/http/client.py", line 351, in begin                                                                                                                       
    version, status, reason = self._read_status()                                                                                                                                    
  File "/usr/lib/python3.4/http/client.py", line 313, in _read_status                                                                                                                
    line = str(self.fp.readline(_MAXLINE + 1), "iso-8859-1")                                                                                                                         
  File "/usr/lib/python3.4/socket.py", line 371, in readinto                                                                                                                         
    return self._sock.recv_into(b)                                                                                                                                                   
socket.timeout: timed out                                                                                                                                                            

During handling of the above exception, another exception occurred:                                                                                                                  

Traceback (most recent call last):                                                                                                                                                   
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/adapters.py", line 370, in send                                                                             
    timeout=timeout                                                                                                                                                                  
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 597, in urlopen                                                   
    _stacktrace=sys.exc_info()[2])                                                                                                                                                   
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/util/retry.py", line 245, in increment                                                     
    raise six.reraise(type(error), error, _stacktrace)                                                                                                                               
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/packages/six.py", line 310, in reraise                                                     
    raise value                                                                                                                                                                      
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 544, in urlopen                                                   
    body=body, headers=headers)                                                                                                                                                      
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 376, in _make_request                                             
    self._raise_timeout(err=e, url=url, timeout_value=read_timeout)                                                                                                                  
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/packages/urllib3/connectionpool.py", line 304, in _raise_timeout                                            
    raise ReadTimeoutError(self, url, "Read timed out. (read timeout=%s)" % timeout_value)                                                                                           
requests.packages.urllib3.exceptions.ReadTimeoutError: HTTPConnectionPool(host='www.libraryofbirmingham.com', port=80): Read timed out. (read timeout=30)                            

During handling of the above exception, another exception occurred:                                                                                                                  

Traceback (most recent call last):                                                                                                                                                   
  File "./bitatawa-client.py", line 231, in check                                                                                                                                    
    timeout=settings.getint("check-timeout", 30))                                                                                                                                    
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/api.py", line 65, in get                                                                                    
    return request('get', url, **kwargs)                                                                                                                                             
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/api.py", line 49, in request                                                                                
    response = session.request(method=method, url=url, **kwargs)                                                                                                                     
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/sessions.py", line 461, in request                                                                          
    resp = self.send(prep, **send_kwargs)                                                                                                                                            
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/sessions.py", line 573, in send                                                                             
    r = adapter.send(request, **kwargs)                                                                                                                                              
  File "/home/jribbens/src/bitatawa/lib/python3.4/site-packages/requests/adapters.py", line 433, in send                                                                             
    raise ReadTimeout(e, request=request)                                                                                                                                            
requests.exceptions.ReadTimeout: HTTPConnectionPool(host='www.libraryofbirmingham.com', port=80): Read timed out. (read timeout=30)                                                  
```


Sorry @jribbens, but you didn't read #1289 or #1915 clearly enough. I will reproduce my statements from those issues again, in the hopes that this will be the last time I have to write this down. =)

This is an unforeseen problem to do with how exception tracebacks are being reported in Python 3. PEP 3134 introduced this 'chaining exceptions' reporting that you can see in the traceback. The purpose of this error reporting is to highlight that some exceptions occur in except blocks, and to work out what chain of exceptions was hit. This is potentially very useful: for instance, you can hit an exception after destroying a resource and then attempt to use that resource in the except block, which hits another exception. It's helpful to be able to see both exceptions at once.

The key is that the `TypeError` raised as the first exception is **unrelated** to the subsequent ones. In fact, that's the standard control flow in urllib3. This means that the real exception that's being raised here is the request.exceptions.ReadTimeout exception that wraps the urllib3.exceptions.ReadTimeoutError exception being raised in urllib3.

The exception that actually bubbled up to the user code is the **last** one, not the first one. The way you read that traceback is as follows:
- I hit a `TypeError` in this method.
- In the `except` block that caught the `TypeError`, I raised a `socket.timeout` (in practice, this is well down the call stack, in a totally standard control flow)
- In the `except` block that caught the `socket.timeout`, I raised a `requests.packages.urllib3.exceptions.ReadTimeoutError`
- In the `except` block that caught the `requests.packages.urllib3.exceptions.ReadTimeoutError`, I raised a `requests.exceptions.ReadTimeout`.
- This exception was never caught.

To be clear, I have stated quite publicly that I think Python 3 screwed users on this 'feature'. I think it's a misfeature that discourages the Easier to Ask Forgiveness than Permission convention in the Python community because it leads to repeated bug reports like this one, even by people who honestly believe that they have read and understood the previous bug reports on this topic.

I promise you, the `ReadTimeout` is exactly what was raised here.


Ah, I see. Thank you for your response. I had wrapped the requests call in a `try: except requests.RequestException` which is why I thought it was not raising `ReadTimeout`, but yet another exception in that block was confusing the issue even further.

Python 3's stack backtrace here does seem to be completely insane. I don't see the point of tracking back past a `raise` unless it was `raise ... from ...`. But this is, of course, not your fault ;-)


> Python 3's stack backtrace here does seem to be completely insane. I don't see the point of tracking back past a raise unless it was raise ... from .... But this is, of course, not your fault ;-)

I'm entirely agreed with you here, this has cost the requests team more time than I'd like. Such is life. =)


Could you not just break the chain with `raise <E> from None`?

```
Python 3.4.1 (v3.4.1:c0e311e010fc, May 18 2014, 00:54:21)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> try:
...     r = 5/0
... except:
...     raise FileNotFoundError
...
Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
ZeroDivisionError: division by zero

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 4, in <module>
FileNotFoundError
>>> try:
...     r = 5/0
... except:
...     raise FileNotFoundError from None
...
Traceback (most recent call last):
  File "<stdin>", line 4, in <module>
FileNotFoundError
```


Nope: we have a common codebase for Python 2 and Python 3, and that syntax isn't valid in Python 2.


Surely a test for legacy python would be worth avoiding all these bug reports?


@Grazfather No, it's a syntax error: Python 2 cannot even parse the file with that in it


A shame. Thanks.


``` python
httplib_response = conn.getresponse(buffering=True)  # This is almost certainly not the error you are looking for!
```


(sorry)