Di Bundle Laravel Package

Getting Started

Minimal Steps

1. Installation:

   composer require da/di-bundle:dev-master
   

   Add to AppKernel.php:

   new Da\DiBundle\DaDiBundle(),
   

2. First Use Case: Replace FileLocator with YamlFileLoader in your bundle’s Extension class:

   use Da\DiBundle\DependencyInjection\Loader\YamlFileLoader;
   
   $loader = YamlFileLoader::decorate($container, new FileLocator(__DIR__.'/../Resources/config'));
   $loader->load('services.yml');
   

3. Enable Custom Parameters: Define a custom parameter (e.g., interface) in services.yml:

   services:
       my_service:
           class: App\Service\MyService
           arguments:
               - '@some_other_service'
           tags:
               - { name: 'my_tag', interface: 'App\Contract\MyInterface' }
   

Implementation Patterns

Core Workflows

1. Decorating Loaders: Use YamlFileLoader::decorate() to wrap existing loaders (e.g., FileLocator) for extended DI features.

   $loader = YamlFileLoader::decorate($container, $existingLocator);
   

2. Custom Parameter Support: Define custom parameters (e.g., interface, priority) in YAML/XML:

   services:
       my_service:
           class: App\Service\MyService
           calls:
               - [setPriority, [100]]
           tags:
               - { name: 'my_tag', interface: 'App\Contract\MyInterface' }
   

3. Integration with Symfony’s DI: Leverage the bundle’s extended ContainerBuilder to validate/process custom parameters before compilation.

Advanced Patterns

• Dynamic Service Configuration: Use the bundle to dynamically generate services based on runtime conditions (e.g., environment variables).

  services:
      dynamic_service:
          class: App\Service\DynamicService
          arguments:
              - '%env(DYNAMIC_VALUE)%'
  

• Tag-Based Grouping: Extend Symfony’s tagging system with custom parameters (e.g., interface for polymorphic services):

  services:
      _defaults:
          autowire: true
          autoconfigure: true
      App\Contract\MyInterface:
          resource: '../src/Contract/MyInterface.php'
          tags: { name: 'my_tag', interface: 'App\Contract\MyInterface' }
  

Gotchas and Tips

Pitfalls

1. Loader Decoration Order: Ensure YamlFileLoader::decorate() is called before loading services to avoid missing custom parameter support.

   // ❌ Wrong: Load first, then decorate.
   $loader->load('services.yml');
   YamlFileLoader::decorate($container, $loader);
   
   // ✅ Correct: Decorate first.
   $loader = YamlFileLoader::decorate($container, $loader);
   $loader->load('services.yml');
   

2. Parameter Validation: Custom parameters (e.g., interface) must be validated in your Configuration class or via ContainerBuilder events. Unvalidated parameters may cause runtime errors.

3. Backward Compatibility: The bundle modifies Symfony’s DI behavior. Test thoroughly with existing services to avoid breaking changes.

Debugging Tips

• Check Compilation Errors: Enable Symfony’s debug mode (APP_DEBUG=1) to catch DI compilation issues early.

  php bin/console debug:container --parameters
  

• Inspect Custom Parameters: Dump the processed configuration to verify custom parameters are parsed correctly:

  $container->dumpService('my_service'); // Check arguments/tags.
  

Extension Points

1. Custom Parameter Handlers: Extend the bundle by implementing Da\DiBundle\DependencyInjection\ParameterHandlerInterface to add support for new parameters (e.g., timeout for HTTP clients).

2. Event Subscribers: Use Symfony’s ContainerBuilder events to intercept and modify service definitions:

   $container->getCompilerPassConfig()->addCompilerPass(new CustomPass());
   

3. Integration with Other Bundles: Combine with SensioFrameworkExtraBundle for route-based service configuration or ApiPlatform for API resource parameters.

Configuration Quirks

• YAML vs. XML: The bundle primarily extends YAML loading. For XML, use XmlFileLoader with similar decoration patterns.
• Parameter Precedence: Custom parameters in YAML override those in PHP config. Use %my_param% for consistency.