Python requests hook returns a value to cause exception

Question

The Documentation for python requests module says for hooks that "If the callback function returns a value, it is assumed that it is to replace the data that was passed in. If the function doesn’t return anything, nothing else is effected" Now i am trying to return a value(int in my case) from my hook function and it throws an exception. This will be valid in all the cases when the return value is an object that DOESNOT have the raw() method defined for it. Here is some code ``` def hook(resp,**kwargs): print resp.url return 1 def main() s = requests.Session() s.hooks = {"response":hook} r = s.get("http://localhost/index.html") ``` And here is the exception: ``` http://localhost/index.html Traceback (most recent call last): File "/home/talha/ws/test.py", line 85, in <module> main() File "/home/talha/ws/test.py", line 72, in main r = s.get("http://localhost/index.html") File "/usr/lib/python2.7/site-packages/requests/sessions.py", line 347, in get return self.request('GET', url, **kwar…

Accepted Answer

If the callback function returns a value, it is assumed that it is to replace the data that was passed in. If the function doesn’t return anything, nothing else is effected.

This means that whatever you return is expected to take the place of the response object you were passed.

Nothing in the documentation states that you can return just anything. What did you expect to happen instead?

If you wanted to return a response that has different data, return something that acts like a response still. This means that either you need to subclass the `requests` response object, or implement something that provides the same API:

```
from requests.models import Response

class MyIntResponse(Response):
    def __init__(self, integer):
        super(MyIntResponse, self).__init__()
        self._content_consumed = True
        self._content = integer

def hook(resp,**kwargs):
    print resp.url
    newresp = MyIntResponse(1)
    newresp.raw = resp.raw  # copy across original HTTP response object
```

You may want to copy over some of the other attributes from the original response; check the documentation on what attributes `Response` objects have.

Python requests hook returns a value to cause exception

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