di.xml Reference Documentation

• Introduction
• File Location
• Syntax
  • <type> Element
  • <arguments> Element
  • <plugin> Element
• Conclusion

Introduction

The di.xml file is a crucial configuration file in Magento 2 that controls the dependency injection (DI) framework. It is used to define and manage dependencies between objects in a Magento installation. This file allows developers to configure how objects are instantiated and how they are injected into other objects.

In this reference documentation, we will explore the structure and syntax of the di.xml file, and explain how to use it to manage dependencies effectively in your Magento 2 project.

File Location

By default, the di.xml file is located in the etc directory of a module. The complete path to the file is app/code/{Vendor}/{Module}/etc/di.xml. For example, if you have a module called MyModule developed by vendor MyVendor, the path to the di.xml file would be app/code/MyVendor/MyModule/etc/di.xml.

Syntax

The di.xml file uses XML syntax to define and configure dependencies. It consists of a root <config> element, which contains multiple <type> elements. Each <type> element represents a class or interface for which dependencies are defined. Within a <type> element, you can have multiple <arguments> and <plugin> elements.

Here's an example of the basic structure of a di.xml file:

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="{Class/Interface}">
        <!-- Define dependencies here -->
    </type>
</config>

Let's examine each component of this structure in detail.

<type> Element

The <type> element is the main building block of the di.xml file. It represents a class or interface for which dependencies are defined. The name attribute of the <type> element specifies the fully qualified class or interface name.

For example, if we want to configure dependencies for the Magento\Catalog\Api\ProductRepositoryInterface interface, the <type> element would look like this:

<type name="Magento\Catalog\Api\ProductRepositoryInterface">
    <!-- Define dependencies here -->
</type>

<arguments> Element

The <arguments> element is used to define constructor arguments for a class. Within the <arguments> element, you can have multiple <argument> elements. Each <argument> element represents a constructor argument.

Here's an example of how to define constructor arguments for the Magento\Catalog\Api\ProductRepositoryInterface interface:

<type name="Magento\Catalog\Api\ProductRepositoryInterface">
    <arguments>
        <argument xsi:type="object" name="productFactory">Magento\Catalog\Model\ProductFactory</argument>
        <argument xsi:type="object" name="resourceModel">Magento\Catalog\Model\ResourceModel\Product</argument>
    </arguments>
</type>

In this example, we define two constructor arguments, namely productFactory and resourceModel. The xsi:type attribute specifies the type of the argument, which can be either object or string. The name attribute specifies the name of the argument, which can be any valid string.

<plugin> Element

The <plugin> element is used to define a plugin for a class. Plugins are used to modify the behavior of existing class methods by intercepting their execution.

To define a plugin, you need to specify the <type> of the class you want to plugin, the <plugin> type (a class that implements the plugin), and the name of the method you want to intercept.

Here's an example of how to define a plugin for the Magento\Catalog\Api\ProductRepositoryInterface interface:

<type name="Magento\Catalog\Api\ProductRepositoryInterface">
    <plugin name="my_plugin" type="MyVendor\MyModule\Plugin\ProductRepositoryPlugin" sortOrder="10" disabled="false"/>
</type>

In this example, we define a plugin with the name my_plugin, implemented by the class MyVendor\MyModule\Plugin\ProductRepositoryPlugin. We also specify the sortOrder attribute to control the order in which plugins are executed, and the disabled attribute to enable or disable the plugin.

Conclusion

The di.xml file is a powerful tool for managing dependencies in Magento 2. By understanding its structure and syntax, you can effectively configure and control how objects are instantiated and injected in your Magento project.

This reference documentation has covered the basic components and syntax of the di.xml file. We hope that this information will help you confidently navigate and utilize the power of the Magento 2 DI framework.