Real-world examples

The decorator pattern is generally used for extending the functionality of an object. In everyday life, examples of such extensions are: adding a silencer to a gun, using different camera lenses, and so on.

In the Django Framework, which uses decorators a lot, we have the View decorators which can be used for (j.mp/djangodec) the following:

• Restricting access to views based on the HTTP request
• Controlling the caching behavior on specific views
• Controlling compression on a per-view basis
• Controlling caching based on specific HTTP request headers

Both the Pyramid Framework and the Zope application server also use decorators to achieve various goals:

• Registering a function as an event subscriber
• Protecting a method with a specific permission
• Implementing the adapter pattern