Extending GraphQL

Adding Fields

New fields can be added to the GraphQL schema, on any object type. This can be used to register a field on a post type object, the global media type, or even an ACF field group. When you need to add a new field, you can find the object type name using the GraphQL IDE.

Add a field to a Type in the GraphQL Schema:


register_graphql_field(string $type_name, string $field_name, array $config);

$type_name (string): The name of the GraphQL Type in the Schema to register the field to
$field_name (string): The name of the field. Should be unique to the Type the field is being registered to.
$config (array): Configuration for the field
- $type (string | array): The name of the GraphQL Type the field will return. The resolve function must return this type. For non-null fields: 'type' => [ 'non_null' => 'TypeName' ] For listOf fields: 'type' => [ 'list_of' => 'TypeName' ]
- $description (string): Description of the field. This will be used to self-document the schema and should describe to clients how the field should be used.
- $resolve (function): Function that will execute when the field is asked for in a query.

Adding Object Types

When adding a new field that should contain subfields, you’ll also want to register an object type.