Source code for oauth_dropins.indieauth

"""IndieAuth drop-in.

https://indieauth.com/developers
"""

import json
import logging
import urllib
import urlparse
from webob import exc

import bs4
import appengine_config
import handlers
import mf2py
import mf2util
import models
import requests
from webutil import util

from google.appengine.ext import ndb


INDIEAUTH_URL = 'https://indieauth.com/auth'


[docs]def discover_authorization_endpoint(me, resp=None): """Fetch a URL and look for authorization_endpoint Link header or rel-value. Args: me: string, URL to fetch resp: requests.Response (optional), re-use response if it's already been fetched Return: string, the discovered indieauth URL or the default indieauth.com URL """ try: resp = resp or util.requests_get(me) except requests.RequestException as e: raise exc.HTTPBadRequest(str(e)) if resp.status_code // 100 != 2: logging.warning( 'could not fetch user url "%s". got response code: %d', me, resp.status_code) return INDIEAUTH_URL # check authorization_endpoint header first auth_endpoint = resp.links.get('authorization_endpoint', {}).get('url') if auth_endpoint: return auth_endpoint # check the html content soup = bs4.BeautifulSoup(resp.text) auth_link = soup.find('link', {'rel': 'authorization_endpoint'}) auth_endpoint = auth_link and auth_link.get('href') if auth_endpoint: return auth_endpoint return INDIEAUTH_URL
[docs]def build_user_json(me, resp=None): """user_json contains an h-card, rel-me links, and "me" Args: me: string, URL of the user, returned by resp: requests.Response (optional), re-use response if it's already been fetched Return: dict, with 'me', the URL for this person; 'h-card', the representative h-card for this page; 'rel-me', a list of rel-me URLs found at this page """ user_json = {'me': me} resp = resp or util.requests_get(me) if resp.status_code // 100 != 2: logging.warning( 'could not fetch user url "%s". got response code: %d', me, resp.status_code) return user_json # Requests doesn't look at the HTML body to find <meta charset> # tags, so if the character encoding isn't given in a header, then # we pass on the raw bytes and let BS4 deal with it. p = mf2py.parse(doc=resp.text if 'charset' in resp.headers.get('content-type', '') else resp.content, url=me) user_json['rel-me'] = p.get('rels', {}).get('me') user_json['h-card'] = mf2util.representative_hcard(p, me) logging.debug('built user-json %r', user_json) return util.trim_nulls(user_json)
[docs]class IndieAuth(models.BaseAuth): """An authenticated IndieAuth user. Provides methods that return information about this user. Stores credentials in the datastore. Key is the domain name. See models.BaseAuth for usage details. """ user_json = ndb.TextProperty(required=True) # generally this has only 'me'
[docs] def site_name(self): return 'IndieAuth'
[docs] def user_display_name(self): """Returns the user's domain.""" return self.key.string_id()
[docs] def access_token(self): """Return the access token, N/A for IndieAuth""" return None
[docs]class StartHandler(handlers.StartHandler): """Starts the IndieAuth flow. Requires the 'me' parameter with the user URL that we want to authenticate. """
[docs] def redirect_url(self, state=None, me=None): assert appengine_config.INDIEAUTH_CLIENT_ID, ( "Please fill in the indieauth_client_id in your app's root directory.") if not me: me = util.get_required_param(self, 'me') parsed = urlparse.urlparse(me) if not parsed.scheme: me = 'http://' + me redirect_uri = self.to_url() endpoint = discover_authorization_endpoint(me) url = endpoint + '?' + urllib.urlencode({ 'me': me, 'client_id': appengine_config.INDIEAUTH_CLIENT_ID, 'redirect_uri': redirect_uri, 'state': util.encode_oauth_state({ 'endpoint': endpoint, 'me': me, 'state': state, }), }) logging.info('Redirecting to IndieAuth: %s', url) return str(url)
[docs]class CallbackHandler(handlers.CallbackHandler): """The callback handler from the IndieAuth request. POSTs back to the auth endpoint to verify the authentication code.""" def get(self): code = util.get_required_param(self, 'code') state = util.decode_oauth_state(util.get_required_param(self, 'state')) endpoint = state.get('endpoint') me = state.get('me') if not endpoint or not me: raise exc.HTTPBadRequest("invalid state parameter") state = state.get('state') or '' validate_resp = util.requests_post(endpoint, data={ 'me': me, 'client_id': appengine_config.INDIEAUTH_CLIENT_ID, 'code': code, 'redirect_uri': self.request.path_url, 'state': state, }) if validate_resp.status_code // 100 == 2: data = util.sniff_json_or_form_encoded(validate_resp.content) if data.get('me'): verified = data.get('me') user_json = build_user_json(verified) indie_auth = IndieAuth(id=verified, user_json=json.dumps(user_json)) indie_auth.put() self.finish(indie_auth, state=state) else: raise exc.HTTPBadRequest( 'Verification response missing required "me" field') else: raise exc.HTTPBadRequest('IndieAuth verification failed: %s %s' % (validate_resp.status_code, validate_resp.text))