What is the differences between type and virtualType? in this article, I assume you already understand about the preferences & type. In this article, I tried to create custom command line of fiko:training

1. I defined helper file of app/code/Fiko/Training/Helper/Data.php (scroll down to see the file).

2. app/code/Fiko/Training/Console/Command/Testing.php defined for the custom command class.

3. app/code/Fiko/Training/etc/di.xml to define custom command and define type & virtualType

• The basic difference is: type will affect all instances, whereas virtualType affects only on sub-class (specific instances)

• if you use type to change class attribute, it will be used by all instances. All instances / classes use that class (app/code/Fiko/Training/Helper/Data.php) will have this value.

app/code/Fiko/Training/Helper/Data.php

<?php

declare(strict_types=1);

namespace Fiko\Training\Helper;

class Data
{
    /** @var array */
    public $data;

    /**
     * Constructor
     *
     * @param array $data
     */
    public function __construct(array $data = [])
    {
        $this->data = $data;
    }

    /**
     * This method will return what's the bypassed parameter
     *
     * @param string $name
     * @return string
     */
    public function getName($name): string
    {
        return "{$this->data['prefix']} {$name}";
    }
}

Notes:

• This class is original file that I will use to practice.

app/code/Fiko/Training/Console/Command/Testing.php

<?php

declare(strict_types=1);

namespace Fiko\Training\Console\Command;

use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;

use Fiko\Training\Helper\Data as HelperData;

class Testing extends Command
{
    private $helper;

    public function __construct(HelperData $helper)
    {
        $this->helper = $helper;

        parent::__construct(null);
    }

    protected function configure(): void
    {
        $this->setName('fiko:training');

        parent::configure();
    }

    /**
     * Execute the command
     *
     * @param InputInterface $input
     * @param OutputInterface $output
     *
     * @return int
     */
     protected function execute(InputInterface $input, OutputInterface $output): int
     {
        $output->writeln($this->helper->getName('Borizqy'));

        return 1;
     }
}

Notes:

• this class is used as the command line executable class.

app/code/Fiko/Training/etc/di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
   <!-- BEGIN: Defining custom command -->
   <type name="Magento\Framework\Console\CommandList">
       <arguments>
           <argument name="commands" xsi:type="array">
               <item name="fiko:training" xsi:type="object">Fiko\Training\Console\Command\Testing</item>
           </argument>
       </arguments>
   </type>
   <!-- END: Defining custom command -->

   <!-- BEGIN: example of type implementation -->
   <type name="Fiko\Training\Helper\Data">
        <arguments>
            <argument name="data" xsi:type="array">
                <item name="prefix" xsi:type="string">Mr.</item>
            </argument>
        </arguments>
   </type>
   <!-- END: example of type implementation -->

   <!-- BEGIN: example of virtualType implementation -->
   <type name="Fiko\Training\Console\Command\Testing">
        <arguments>
            <argument name="helper" xsi:type="object">data_example</argument>
        </arguments>
   </type>
   <virtualType name="data_example" type="Fiko\Training\Helper\Data">
        <arguments>
            <argument name="data" xsi:type="array">
                <item name="prefix" xsi:type="string">Tuan</item>
            </argument>
        </arguments>
   </virtualType>
   <!-- END: example of virtualType implementation -->
</config>

Notes:

• Defining custom command, to define the custom command line of bin/magento fiko:training

• example of type implementation, all instances use Fiko\Training\Helper\Data will have $data['prefix'] and the value is Mr..

• example of virtualType implementation, specifically Fiko\Training\Helper\Data used by Fiko\Training\Console\Command\Testing will have have $data['prefix'] and the value is Tuan.

References:

• https://www.codedecorator.com/blog/what-is-the-difference-between-type-and-virtualtype-practical-example/

• https://medium.com/@mishra.anshu1710/magento2-difference-between-type-and-virtual-type-5ac4d2e46568

• https://magently.com/blog/magento-2-design-patterns-preferences-virtual-types/