Simple PHP Dependency Injection with Interfaces Example

By on

I created this graphic as a simple way to visualize dependency injection, unit testing and the use of php interfaces. The interface provides the “agreement/contract” between the implementations and  class \ControllerForExample. You can see that $httpClient can be any one of the implementations. \ControllerForExample doesn’t need to know the details of each implementation, only that the contract/implementation is valid.

View Full Size Graphic
php dependency injection and interfaces