Merge pull request #152 from alleyinteractive/150-add-support-for-gra…

…phql-via-wpgraphql-hooks

Add support for GraphQL via WPGraphQL hooks

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All notable changes to `WP Curate` will be documented in this file.
 
+## 1.8.0 - 2024-03-19
+
+- Enhancement: Integration with [WPGraphQL plugin](https://wordpress.org/plugins/wp-graphql/) to support custom GraphQL interface type and connection.
+
 ## 1.7.1 - 2024-03-13
 
 - Bug Fix: Query block does not update with posts from custom post types when selected in Query Paramaters block settings.

src/features/class-graphql.php

@@ -0,0 +1,141 @@
+<?php
+/**
+ * GraphQL class file
+ *
+ * @package wp-curate
+ */
+
+namespace Alley\WP\WP_Curate\Features;
+
+use Alley\WP\Types\Feature;
+use WPGraphQL\AppContext;
+use GraphQL\Type\Definition\ResolveInfo;
+use WPGraphQL\Data\Connection\PostObjectConnectionResolver;
+
+/**
+ * Add support for GraphQL, if WPGraphQL plugin exists.
+ */
+final class GraphQL implements Feature {
+	/**
+	 * Post types allowed in GraphQL.
+	 *
+	 * @var string[]
+	 */
+	private $allowed_post_types;
+
+	/**
+	 * Get the GraphQL Type by Post Type.
+	 *
+	 * @param  string $post_type_string Name of the post type. Ex: 'post'.
+	 *
+	 * @return string GraphQL Type name. Ex: 'Post'.
+	 */
+	private function get_graphql_type_by_post_type( string $post_type_string ): string {
+		$post_type_object = get_post_type_object( $post_type_string );
+
+		// Only return a GraphQL type for allowed post types in WP Curate.
+		if ( ! in_array( $post_type_string, $this->allowed_post_types, true ) ) {
+			return '';
+		}
+
+		if ( empty( $post_type_object ) ) {
+			return '';
+		}
+
+		// @phpstan-ignore-next-line
+		return ucfirst( $post_type_object->graphql_single_name );
+	}
+
+	/**
+	 * Get GraphQL Types from allowed post types.
+	 *
+	 * @return array<string>
+	 */
+	private function get_types_from_allowed_post_types(): array {
+		$interface_to_types = [];
+
+		foreach ( $this->allowed_post_types as $post_type ) {
+			$interface_to_types[] = $this->get_graphql_type_by_post_type( $post_type );
+		}
+
+		return $interface_to_types;
+	}
+
+	/**
+	 * Set up.
+	 */
+	public function __construct() {
+		$this->allowed_post_types = apply_filters( 'wp_curate_allowed_post_types', [ 'post' ] );
+	}
+
+	/**
+	 * Boot the feature.
+	 */
+	public function boot(): void {
+		add_action( 'graphql_register_types', [ $this, 'graphql_register_types' ] );
+	}
+
+	/**
+	 * Register types in WPGraphQL
+	 *
+	 * @return void
+	 */
+	public function graphql_register_types(): void {
+
+		/**
+		 * Add an Interface Type for WP Curate to the registry.
+		 *
+		 * @see https://www.wpgraphql.com/functions/register_graphql_interface_type
+		 */
+		register_graphql_interface_type( // @phpstan-ignore-line
+			'WPCurateInterface',
+			[
+				'description' => __( 'Represents the interface type a WP Curate post', 'wp-curate' ),
+				'interfaces'  => [ 'ContentNode', 'NodeWithTitle', 'NodeWithFeaturedImage' ],
+				'fields'      => [],
+				'resolveType' => function ( $node ) {
+					return $this->get_graphql_type_by_post_type( $node->post_type );
+				},
+			]
+		);
+
+
+		/**
+		 * Apply the WP Curate interface to registered GraphQL Types.
+		 * Types can be filtered to include project specific custom post types.
+		 *
+		 * @see https://www.wpgraphql.com/functions/register_graphql_interfaces_to_types
+		 */
+		register_graphql_interfaces_to_types( [ 'WPCurateInterface' ], $this->get_types_from_allowed_post_types() ); // @phpstan-ignore-line
+
+		/**
+		 * Register a new connection field named 'wpCuratePosts' on `RootQuery`
+		 * to access WP Curate posts. Supports Inline Fragments when constructing
+		 * your GraphQL query.
+		 *
+		 * @see https://www.wpgraphql.com/functions/register_graphql_connection
+		 */
+		register_graphql_connection( // @phpstan-ignore-line
+			[
+				'fromType'       => 'RootQuery',
+				'toType'         => 'WPCurateInterface',
+				'fromFieldName'  => 'wpCuratePosts',
+				'connectionArgs' => [
+					'in' => [
+						'type'        => [ 'list_of' => 'ID' ],
+						'description' => __( 'Array of IDs for the objects to retrieve', 'wp-curate' ),
+					],
+				],
+				// @phpstan-ignore-next-line
+				'resolve'        => function ( $source, $args, AppContext $context, ResolveInfo $info ) {
+					$resolver = new PostObjectConnectionResolver( $source, $args, $context, $info ); // @phpstan-ignore-line
+
+					$resolver->set_query_arg( 'post__in', $args['where']['in'] ); // @phpstan-ignore-line
+					$resolver->set_query_arg( 'post_type', $this->allowed_post_types ); // @phpstan-ignore-line
+
+					return $resolver->get_connection(); // @phpstan-ignore-line
+				},
+			],
+		);
+	}
+}

src/main.php

@@ -41,6 +41,7 @@ function main(): void {
 	$features[] = new Features\Parsely_Support();
 
 	$features[] = new Features\Rest_Api();
+	$features[] = new Features\GraphQL();
 
 	foreach ( $features as $feature ) {
 		$feature->boot();

wp-curate.php

@@ -3,7 +3,7 @@
  * Plugin Name: WP Curate
  * Plugin URI: https://github.com/alleyinteractive/wp-curate
  * Description: Plugin to curate homepages and other landing pages
- * Version: 1.7.1
+ * Version: 1.8.0
  * Author: Alley Interactive
  * Author URI: https://github.com/alleyinteractive/wp-curate
  * Requires at least: 6.4