Added the ability to use custom renderers for the JWT endpoints.

[Jwpe]

Ran into a use-case today where I wanted to modify the format of the error response from a failed login attempt. I've already written a DRF custom renderer to neatly wrap my responses and errors, and I thought it would be cool if I could apply this renderer to the JWT endpoints as well.

As far as I can tell it's an extremely simple change! Would definitely appreciate thoughts and feedback though.

[Jwpe]

@jpadilla does this seem like something you'd want to add?

[jpadilla]

@Jwpe wouldn't just setting DEFAULT_RENDERER_CLASSES work? You can also do something like:

urlpatterns = [
    url(r'^api-token-auth/', ObtainJSONWebToken.as_view(renderer_classes=[CustomRenderer]),
]

[Jwpe]

@jpadilla the first suggestion wouldn't work, unfortunately, because the render_classes on the base view is hard-coded as rest_framework.renderers.JSONRenderer. It could be made to work if that was changed just to use DRF's DEFAULT_RENDERER_CLASSES - might be preferable to a specific setting just for this.

The second way does work, but in my mind it's less elegant than permitting a global setting. It requires importing the view and the custom renderer into your urls.py.

Maybe a good middle ground would just be changing the base class to have:

from rest_framework.settings import api_settings as drf_api_settings
...

class JSONWebTokenAPIView(APIView):
...
renderer_classes =  drf_api_settings.DEFAULT_RENDERER_CLASSES

[jpadilla]

@Jwpe I'm thinking parser_classes and renderer_classes are better off removed. It'll just default to whatever you set on your DRF settings. Thoughts?

[Jwpe]

@jpadilla that totally works. It would be a lot simpler. If you like I can change the PR to reflect that?

[jpadilla]

@Jwpe that'd be great, yeah!

[Jwpe]

@jpadilla modified this and rebased to take out the irrelevant changes I made before.

[jpadilla]

@Jwpe thanks!