How to Extend an existing GraphQL schema

In this article, We will learn about how to extend an existing GraphQL schema from our module.

First off, We will create a module.

Step-1: Define the configuration field in  etc/graphql/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">
  <type name="Magento\StoreGraphQl\Model\Resolver\Store\StoreConfigDataProvider">
    <arguments>
      <argument name="extendedConfigData" xsi:type="array">
        <item name="section_group_field" xsi:type="string">section/group/field</item>
      </argument>
    </arguments>
  </type>
</config>

Step-2: Extend the type storeConfig in etc/schema.graphqls file.

type StoreConfig {
    section_group_field : String  @doc(description: "Extended Config Data - section/group/field")
}

Step-3: Write our custom query in ChromeiQl.

{
  storeConfig{
    section_group_field
  }
}

Hope this will help you.

Thanks 🙂