Introduction

Autocache addresses two of the most common scenarios for caching and cache invalidation for django models: instance caching and related objects caching.

Instance Caching

This is the practice of caching individual model instances. Autocache provides a CacheController that you can attach to models to cause automatic caching and invalidations.

class Model(django.models.Model):
    cache = autocache.CacheController()
    field = django.models.TextField()

Model.objects.get(pk=27)    # hits the database
Model.cache.get(27)         # Tries cache first

Related Objects Caching

Having fetched an instance of a model, a frequent database operation is to find all the instances of another model that are related to your instance via foreign keys. You can attach a RelatedCacheController to your model to enable automatic caching and invalidation of these relations.

instance = Model.cache.get(pk=27)
related_things = instance.things_set.all()  # hits the database
related_things = instance.cache.things_set  # Tries cache first

The RelatedCacheController will automatically detect and cache objects related to the model it resides on by ForeignKeys, ManyToManyFields, and OneToOneFields.