PSR11

PSR11, also known as the Container Interface, is a PHP Standard Recommendation that defines a common interface for dependency injection containers. It aims to standardize how libraries and frameworks interact with container implementations, making it easier to swap out different container solutions without altering application code. The core of PSR11 is the Container Interface, which specifies two methods: get() and has().

The get() method is used to retrieve an object or value from the container by its identifier, typically a string. If the identifier is not found in the container, it should throw a NotFoundException. The has() method checks if an identifier exists within the container, returning a boolean value. This interface provides a simple yet effective way to abstract away the complexities of dependency management.

Many popular PHP dependency injection containers, such as PHP-DI, Symfony's DependencyInjection component, and League Container, have implemented the PSR11 interface. This widespread adoption means that developers can rely on a consistent way to access services regardless of the underlying container technology. The benefits include improved portability of code, reduced vendor lock-in, and a more predictable development experience when working with reusable components or libraries. PSR11 has become a foundational standard in the modern PHP ecosystem.