Summary
In this chapter, you built a follow system using many-to-many relationships with an intermediary model. You also created an activity stream using generic relations and you optimized QuerySets to retrieve related objects. This chapter then introduced you to Django signals, and you created a signal receiver function to denormalize related object counts. We covered application configuration classes, which you used to load your signal handlers. You also learned how to install and configure Redis in your Django project. Finally, you used Redis in your project to store item views, and you built an image ranking with Redis.
In the next chapter, you will learn how to build an online shop. You will create a product catalog and build a shopping cart using sessions. You will also discover how to launch asynchronous tasks using Celery.
