Support using custom function in request.auth

[sohoffice]

As stated in the requests document, user may pass a sub class of AuthBase as the auth parameter. This is very useful when the authentication is a little bit more complicated than passing the session token or basic auth.

I guess this can be worked around by allowing user to pass a custom function which return AuthBase subclass? Something similar to the below.

request:
  auth:
    $ext:
      function: security:prepare_auth
      extra_kwargs:
        username: "{username_variable}"

In the security.py, the caller can do the below

from requests.auth import AuthBase

class PizzaAuth(AuthBase):
    """Attaches HTTP Pizza Authentication to the given Request object."""
    def __init__(self, username):
        # setup any auth-related data here
        self.username = username

    def __call__(self, r):
        # modify and return the request
        r.headers['X-Pizza'] = self.username
        return r

def prepare_auth(**kwargs):
    username = kwargs['username']
    return PizzaAuth(username)

I hope this makes sense ?

I do have a fix which can be submitted shortly. Let me know what you think.

[sohoffice]

In case anyone is interested, I've a branch for the above feature.
The branch allows us to use a custom function as request.auth.
It may be installed via pip install git+https://github.com/sohoffice/tavern.git@douglas/auth-function

[jesuslinares]

Any update on this?
It would be very useful to use along with requests-aws4auth.
Thanks!