apigility-app

Static access to the Application and ServiceManager objects from within Apigility

This module allows a developer to get an instance of the Application object from anywhere in the application. Through the Application object, developers have access to the ServiceManager, ModuleManager, EventManager and other objects that were previously difficult to access from within a standard class.

Having access to the ServiceManager makes it possible to use the pre-defined factories to create "new" instances of classes and thus to avoid the PHP new operation. This solves several problems with testing. The test can create a mock, set this in the ServiceManager ahead of time, and this mock will be given to the requesting class (presumably, the subject under test) in place of the actual class.

This module should not be used in place of good dependency injection designs. We have developed it as a remedy for legacy code as we refactor it step-by-step. If development schedules allow, we expect to use this code only in a transition phase. But this is the real world.

Installation

This package is set up for installation via Composer.

php composer.phar require dealerinspire/apigility-app

Then you must add this module to your config/application.config.php file. Within the modules array, add 'DealerInspire\\ApigilityApp'.

return [
    'modules' => [
        ...
        'DealerInspire\\ApigilityApp'
    ],
]

Usage

If properly initialized, retrieving the Application object or the ServiceManager object is a static call.

$application = App::getApplication();
$serviceManager = App::getServiceManager();

For convenience, there is a get method that will return any class or alias known to the ServiceManager.

$config = App::get('config');
$myClass = App::get(MyClass::class);

Classes you want to retrieve in this way must be properly set up with factories. Simple classes with no dependencies can be defined as "invokables". As an example, your module.config.php might contain lines like the following.

return [
    'service_manager' => [
        'factories' => [
            MyClass::class => function(ContainerInterface $container, $requestedName) {
                return new MyClass(
                    $container->get(SimpleClass::class)
                );
            }
        ],
        'invokables' => [
            SimpleClass::class => SimpleClass::class,
        ],
    ],
];

For other ServiceManager options, refer to Configuring the Service Manager.

Modifications to Unit Tests

You may find that the App class is not properly initialized in your unit test environment. Typically, this is evidenced by an exception with a message "call to getServiceManager on null". This indicates that the modules have not been loaded or that the Application object has not been initialized (it must call the 'bootstrap' event).

Somewhere within your TestCase, you need to include code similar to the following.

use Zend\Mvc\Service\ServiceManagerConfig;
use Zend\ServiceManager\ServiceManager;
use ZF\Apigility\Application;

$config = require('../config/application.config.php');

$serviceManager = new ServiceManager(new ServiceManagerConfig());
$serviceManager->setService('ApplicationConfig', $config);
$serviceManager->get('ModuleManager')->loadModules();
$application = new Application($config, $serviceManager);
$application->bootstrap();

You will almost certainly need to modify the paths within your $config variable so they are referenced from your test directory. Expect other changes, too. This subject is beyond our scope here but you can make it work! I believe in you!