Get request parameters for redirect url.

def get_redirect_args(self, request, callback):
        """Get request parameters for redirect url."""
        callback = request.build_absolute_uri(callback)
        args = {
            'client_id': self.consumer_key,
            'redirect_uri': callback,
            'response_type': 'code',
        }

        scope = self.get_scope(request)
        if scope:
            args['scope'] = self.scope_separator.join(self.get_scope(request))

        state = self.get_application_state(request, callback)
        if state is not None:
            args['state'] = state
            request.session[self.session_key] = state

        auth_params = self.get_auth_params(request)
        if auth_params:
            args.update(auth_params)

        return args