Add WooCommerce Product Bundles to GraphQL API

product-bundle.php

<?php

namespace App\GraphQL;

const TYPE_BUNDLE_PRODUCT = 'BundleProduct';

/**
 * Register BundleProduct Type
 */
add_action( 'graphql_register_types', function () {
	
	/**
	 * Register our bundle object type
	 */
	register_graphql_object_type( TYPE_BUNDLE_PRODUCT, [
			'description' => 'A product bundle object',
			'interfaces'  => [ 'Node', 'Product' ],
			'fields'      =>
				[
					'bundlePriceMin' => [
						'type'    => 'String',
						'resolve' => function ( $source ) {
							return $source->get_bundle_price( 'min' );
						}
					],
					'bundlePriceMax' => [
						'type'    => 'String',
						'resolve' => function ( $source ) {
							return $source->get_bundle_price( 'max' );
						}
					],
					'groupMode'=> [
						'type'    => 'String',
						'resolve' => function ( $source ) {
							return $source->get_group_mode();
						}
					],
					'price' => [
						'type'    => 'String',
						'resolve' => function ( $source ) {
							return $source->get_price();
						},
					],
					'salePrice' => [
						'type'    => 'String',
						'resolve' => function ( $source ) {
							return $source->get_sale_price();
						},
					],
					'regularPrice' => [
						'type'    => 'String',
						'resolve' => function ( $source ) {
							return $source->get_regular_price();
						},
					],
					'bundledItems' => [
						'type'    => 'String',
						'resolve' => function ( $source ) {
              						return 'tbd. still need to solve this.';
						},
					],
          				// still need to add more fields...
				],
		]
	);
	
	
	/**
	 * Register root query for bundle
   	 *
   	 * @todo - still need to provide args to pass in filter values such as ID
	 */
	register_graphql_field(
		'RootQuery',
		'bundleProduct',
		[
			'type' => TYPE_BUNDLE_PRODUCT,
		]
	);
	
} );

/**
 * Add the `bundle` type to GraphQL product types
 */
add_filter( 'graphql_woocommerce_product_types', function ( $product_types ) {
	$product_types['bundle'] = TYPE_BUNDLE_PRODUCT;
	
	return $product_types;
} );

/**
 * Add the bundle to the product input->where to allow for filtering by bundles
 */
add_filter( 'graphql_product_types_enum_values', function ( $values ) {
	$values['BUNDLE'] = [
		'value'       => 'bundle',
		'description' => 'A bundle product',
	];
	
	return $values;
} );