How to make extension to perform custom initialization on a Magento 2 start

October 12, 2015 - Magento 2

There are at least two use cases in this situation. In Magento 2 you can custom mini-libraries with such short popular global functions as rm_customer_logged_in():

<type name='\Magento\Framework\AppInterface'>
    <plugin
        name='Df\Framework\AppInterfacePlugin'
        type='Df\Framework\AppInterfacePlugin'
        sortOrder='100'
    />
</type>

<?php
namespace Df\Framework;
use \Magento\Framework\AppInterface;
class AppInterfacePlugin {
    /**
    * @see \Magento\Framework\AppInterface::launch()
    * @param AppInterface $subject
    * @return array
    */
    public function beforeLaunch(AppInterface $subject) {
        // Place your custom initialization code here.
        return [];
    }
}

<plugin

name='Df\Framework\AppInterfacePlugin'

type='Df\Framework\AppInterfacePlugin'

sortOrder='100'

</type>

<?php

namespace Df\Framework;

use \Magento\Framework\AppInterface;

class AppInterfacePlugin {

/**

* @see \Magento\Framework\AppInterface::launch()

* @param AppInterface $subject

* @return array

public function beforeLaunch(AppInterface $subject) {

// Place your custom initialization code here.

return [];

}

Unfortunately, such approach does not work for console apps. Therefore, for applications like setup:upgrade, use event handlers:

<event name='store_collection_load_before'>
    <observer
        name='Df\Core\Boot'
        instance='Df\Core\Boot'
        method='storeCollectionLoadBefore'
    />
</event>

<?php
namespace Df\Core;
use \Magento\Framework\Event\Invoker\InvokerDefault;
use \Magento\Framework\Event\Observer as _O;
class Boot {
    /**
    * @used-by InvokerDefault::_callObserverMethod()
    * @param _O $o
    * @return void
    */
    public function storeCollectionLoadBefore(_O $o) {
        if (!self::$_done && 'cli' === PHP_SAPI) {
            self::run();
        }
    }
    // other code here...
}