Create Django cache backed OpenID provider store

common/djangoapps/external_auth/djangostore.py

+"""A openid store using django cache"""
+
+from openid.store.interface import OpenIDStore
+from openid.store import nonce
+
+from django.core.cache import cache
+
+import logging
+import time
+
+DEFAULT_ASSOCIATION_TIMEOUT = 60
+DEFAULT_NONCE_TIMEOUT = 600
+
+ASSOCIATIONS_KEY_PREFIX = 'openid.provider.associations.'
+NONCE_KEY_PREFIX = 'openid.provider.nonce.'
+
+log = logging.getLogger('DjangoOpenIDStore')
+
+
+def get_url_key(server_url):
+    key = ASSOCIATIONS_KEY_PREFIX + server_url
+    return key
+
+
+def get_nonce_key(server_url, timestamp, salt):
+    key = '{prefix}{url}.{ts}.{salt}'.format(prefix=NONCE_KEY_PREFIX,
+                                             url=server_url,
+                                             ts=timestamp,
+                                             salt=salt)
+    return key
+
+
+class DjangoOpenIDStore(OpenIDStore):
+    def __init__(self):
+        log.info('DjangoStore cache:' + str(cache.__class__))
+
+    def storeAssociation(self, server_url, association):
+        key = get_url_key(server_url)
+
+        log.info('storeAssociation {0}'.format(key))
+
+        associations = cache.get(key, {})
+        associations[association.handle] = association
+
+        cache.set(key, associations, DEFAULT_ASSOCIATION_TIMEOUT)
+
+    def getAssociation(self, server_url, handle=None):
+        key = get_url_key(server_url)
+
+        log.info('getAssociation {0}'.format(key))
+
+        associations = cache.get(key)
+
+        association = None
+
+        if associations:
+            if handle is None:
+                # get best association
+                valid = [a for a in associations if a.getExpiresIn() > 0]
+                if valid:
+                    association = valid[0]
+            else:
+                association = associations.get(handle)
+
+        # check expiration and remove if it has expired
+        if association and association.getExpiresIn() <= 0:
+            if handle is None:
+                cache.delete(key)
+            else:
+                associations.pop(handle)
+                cache.set(key, association, DEFAULT_ASSOCIATION_TIMEOUT)
+            association = None
+
+        return association
+
+    def removeAssociation(self, server_url, handle):
+        key = get_url_key(server_url)
+
+        log.info('removeAssociation {0}'.format(key))
+
+        associations = cache.get(key)
+
+        removed = False
+
+        if associations:
+            if handle is None:
+                cache.delete(key)
+                removed = True
+            else:
+                association = associations.pop(handle)
+                if association:
+                    cache.set(key, association, DEFAULT_ASSOCIATION_TIMEOUT)
+                    removed = True
+
+        return removed
+
+    def useNonce(self, server_url, timestamp, salt):
+        key = get_nonce_key(server_url, timestamp, salt)
+
+        log.info('useNonce {0}'.format(key))
+
+        if abs(timestamp - time.time()) > nonce.SKEW:
+            return False
+
+        anonce = cache.get(key)
+
+        found = False
+
+        if anonce is None:
+            cache.set(key, '-', DEFAULT_NONCE_TIMEOUT)
+            found = False
+        else:
+            found = True
+
+        return found
+
+    def cleanupNonces(self):
+        # not necesary, keys will timeout
+        return 0
+
+    def cleanupAssociations(self):
+        # not necesary, keys will timeout
+        return 0

common/djangoapps/external_auth/views.py

@@ -7,6 +7,7 @@ import string
 import fnmatch
 
 from external_auth.models import ExternalAuthMap
+from external_auth.djangostore import DjangoOpenIDStore
 
 from django.conf import settings
 from django.contrib.auth import REDIRECT_FIELD_NAME, authenticate, login
@@ -30,7 +31,6 @@ from openid.consumer.consumer import SUCCESS
 
 from openid.server.server import Server
 from openid.server.trustroot import TrustRoot
-from openid.store.filestore import FileOpenIDStore
 from openid.extensions import ax, sreg
 
 import student.views as student_views
@@ -400,7 +400,7 @@ def provider_login(request):
         return default_render_failure(request, "Invalid OpenID request")
 
     # initialize store and server
-    store = FileOpenIDStore('/tmp/openid_provider')
+    store = DjangoOpenIDStore()
     server = Server(store, endpoint)
 
     # handle OpenID request