emilyhorsman/socialauth

import jwt

import socialauth.providers
from . import InvalidUsage


def validate_provider(provider):
    return provider in (
        'twitter',
        'facebook',
    )


def http_get_provider(provider,
                      request_url, params, token_secret, token_cookie = None):
    '''Handle HTTP GET requests on an authentication endpoint.

    Authentication flow begins when ``params`` has a ``login`` key with a value
    of ``start``. For instance, ``/auth/twitter?login=start``.

    :param str provider: An provider to obtain a user ID from.
    :param str request_url: The authentication endpoint/callback.
    :param dict params: GET parameters from the query string.
    :param str token_secret: An app secret to encode/decode JSON web tokens.
    :param str token_cookie: The current JSON web token, if available.
    :return: A dict containing any of the following possible keys:

        ``status``: an HTTP status code the server should sent

        ``redirect``: where the client should be directed to continue the flow

        ``set_token_cookie``: contains a JSON web token and should be stored by
        the client and passed in the next call.

        ``provider_user_id``: the user ID from the login provider

        ``provider_user_name``: the user name from the login provider
    '''

    if not validate_provider(provider):
        raise InvalidUsage('Provider not supported')

    klass    = getattr(socialauth.providers, provider.capitalize())
    provider = klass(request_url, params, token_secret, token_cookie)
    if provider.status == 302:
        ret = dict(status = 302, redirect = provider.redirect)
        tc  = getattr(provider, 'set_token_cookie', None)
        if tc is not None:
            ret['set_token_cookie'] = tc

        return ret

    if provider.status == 200 and provider.user_id is not None:
        ret = dict(status = 200, provider_user_id = provider.user_id)
        if provider.user_name is not None:
            ret['provider_user_name'] = provider.user_name

        return ret

    raise InvalidUsage('Invalid request')  # pragma: no cover