Fix astakos stale session messages

Consume session messages in get_services api response. When get_services is
loaded from an astakos page, messages should have already been consumed
in the html response. When get_services is loaded from another
domain/service we consume them in get_services view so that no stale
messages to appear if user visits an astakos view later on.

snf-astakos-app/astakos/im/api/__init__.py

@@ -40,6 +40,7 @@ from django.utils import simplejson as json
 from django.conf import settings
 from django.core.urlresolvers import reverse
 from django.utils.translation import ugettext as _
+from django.contrib import messages
 
 from astakos.im.models import AstakosUser, Service, Resource
 from astakos.im.api.faults import (
@@ -103,6 +104,15 @@ def get_services(request):
     data = json.dumps(get_services_dict())
 
     if callback:
+        # Consume session messages. When get_services is loaded from an astakos
+        # page, messages should have already been consumed in the html
+        # response. When get_services is loaded from another domain/service we
+        # consume them here so that no stale messages to appear if user visits
+        # an astakos view later on.
+        # TODO: messages could be served to other services/sites in the dict
+        # response of get_services and/or get_menu. Services could handle those
+        # messages respectively.
+        messages_list = list(messages.get_messages(request))
         mimetype = 'application/javascript'
         data = '%s(%s)' % (callback, data)