Dependency Injection

This document provides a guide for developers on how to use and configure dependency injection in the WebFramework. The framework uses PHP-DI for managing dependencies, allowing you to define and override services and classes in a flexible manner.

Overview

Dependency injection in WebFramework is managed using PHP-DI, a powerful dependency injection container for PHP. It allows you to define how classes and services are instantiated and configured, making it easy to manage dependencies across your application.

The BootstrapService and SlimAppTask classes are responsible for setting up the dependency injection container and registering services. They use the configured definition files to do this.

Default Definition Files

The base configuration specifies a default set of definition files that are used for dependency injection. These files are:

• /vendor/avoutic/web-framework/definitions/web_framework_definitions.php
• /definitions/app_definitions.php

Meaning that if will load the base definition file from the WebFramework, then the application definition file.

Setting Another Set of Files

To set your own definition files, you need to specify them in the base_config.php file under the definition_files key. These files contain PHP-DI definitions that configure how services and classes are instantiated.

Example Configuration

return [
    // Other configuration settings...

    'definition_files' => [
        '/vendor/avoutic/web-framework/definitions/web_framework_definitions.php',
        '/definitions/my_definitions.php', // Your custom definitions
    ],
];

In this example, my_definitions.php is a custom definition file that you can use to define your own services and override existing ones.

Overriding Classes

To override a class like Instrumentation, you need to provide a new implementation in your definition file. This is done using PHP-DI's autowire and constructor methods.

Example: Overriding Instrumentation

Suppose you want to replace the default Instrumentation implementation with a custom one. You can do this by adding the following entry to your definition file:

use App\Instrumentation\CustomInstrumentation;
use WebFramework\Core\Instrumentation;

return [
    Instrumentation::class => DI\autowire(CustomInstrumentation::class),
];

In this example, CustomInstrumentation is a class that implements the Instrumentation interface. By using DI\autowire, PHP-DI will automatically inject dependencies into the CustomInstrumentation class.

For more information on PHP-DI, see the PHP-DI documentation.