"""

Copyright 2015 Archive Analytics Solutions - University of Liverpool

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
"""

from django.core.cache import cache

class CassandraAuth(object):

    def process_request(self, request):
        from indigo.models import User

        username = request.session.get('user')
        if not username:
            return None

        # Cache the user rather than hitting the database for
        # each request.  We can also invalidate the entry if the
        # user is marked as inactive.
        user = cache.get('user_{}'.format(username), None)
        if not user:
            user = User.find(username)
        request.user = user
        cache.set('user_{}'.format(username), user, 60)

        return None