Django Design Patterns and Best Practices - Second Edition

Problem details

While designing models, you might find certain common attributes or behaviors shared across model classes. For example, a post and comment model needs to keep track of its created date and modified date. Manually copying and pasting the fields and their associated method is not a very DRY approach.

Since Django models are classes, object-oriented approaches such as composition and inheritance are possible solutions. However, compositions (by having a property that contains an instance of the shared class) will need an additional level of indirection to access fields.

Inheritance can get tricky. We can use a common base class for post and comments. However, there are three kinds of inheritance in Django: concrete, abstract, ...