Anonymous Tracking Middleware for Django

gistfile1.py

import uuid
import base64
from trubrain.settings import (
    ANON_TRACKING_COOKIE,
    ANON_TRACKING_COOKIE_MAX_AGE
)


class AnonTrackingMiddleware(object):
    salt = 'anon_tracking'

    def _get_cookie(self, request):
        return request.get_signed_cookie(
            ANON_TRACKING_COOKIE, None, salt=self.salt
        )

    def _set_cookie(self, response, anon_uuid):
        response.set_signed_cookie(
            ANON_TRACKING_COOKIE,
            anon_uuid,
            max_age=ANON_TRACKING_COOKIE_MAX_AGE,
            salt=self.salt,
        )

    def _delete_cookie(self, response):
        response.delete_cookie(ANON_TRACKING_COOKIE)

    def process_request(self, request):
        # If ANON_TRACKING_COOKIE cookie set, save value in request
        if not request.user.is_authenticated():
            anon_uuid = self._get_cookie(request)
            if anon_uuid is not None:
                request.anon_uuid = anon_uuid
            else:
                request.anon_uuid = str(uuid.uuid4())

    def process_response(self, request, response):
        # If not authenticated and cookie is None, set new anon_uuid
        if hasattr(request, 'user') and not request.user.is_authenticated():
            if self._get_cookie(request) is None and \
               hasattr(request, 'anon_uuid'):
                self._set_cookie(response, request.anon_uuid)
        elif hasattr(request, 'user') and request.user.is_authenticated():
            # Just in case if the user is authenticated we delete the cookie
            # response.delete_cookie fails silently if no cookie exists.
            self._delete_cookie(response)

        return response