wp-graphql-tax-query.php

<?php
/**
 * Plugin Name: WPGraphQL Tax Query
 * Plugin URI: https://github.com/wp-graphql/wp-graphql-tax-query
 * Description: Tax_Query support for the WPGraphQL plugin. Requires WPGraphQL version 0.4.0 or newer.
 * Author: WPGraphQL, Jason Bahl
 * Author URI: https://www.wpgraphql.com
 * Version: 0.2.0
 * Text Domain: wp-graphql-tax-query
 * Requires at least: 4.7.0
 * Tested up to: 4.7.1
 *
 * @package WPGraphQLTaxQuery
 * @category Core
 * @author Digital First Media, Jason Bahl
 * @version 0.1.0
 */
namespace WPGraphQL;

// Exit if accessed directly.
use WPGraphQL\Registry\TypeRegistry;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}


class TaxQuery {

	/**
	 * This holds the TaxQuery input type object
	 * @var $tax_query
	 */
	private static $tax_query;

	/**
	 * TaxQuery constructor.
	 *
	 * This hooks the plugin into the WPGraphQL Plugin
	 *
	 * @since 0.0.1
	 */
	public function __construct() {

		/**
		 * Setup plugin constants
		 * @since 0.0.1
		 */
		$this->setup_constants();

		/**
		 * Included required files
		 * @since 0.0.1
		 */
		$this->includes();

		// Register Tax Query Types
		add_action( get_graphql_register_action(), [ $this, 'register_types' ], 10, 1 );

		/**
		 * Filter the query_args for the PostObjectQueryArgsType
		 * @since 0.0.1
		 */
		add_filter( 'graphql_input_fields', [ $this, 'add_input_fields' ], 10, 4 );

		/**
		 * Filter the $allowed_custom_args for the PostObjectsConnectionResolver to map the
		 * taxQuery input to WP_Query terms
		 * @since 0.0.1
		 */
		add_filter( 'graphql_map_input_fields_to_wp_query', [ $this, 'map_input_fields' ], 10, 2 );

	}

	/**
	 * Setup plugin constants.
	 *
	 * @access private
	 * @since 0.0.1
	 * @return void
	 */
	private function setup_constants() {

		// Plugin version.
		if ( ! defined( 'WPGRAPHQL_TAXQUERY_VERSION' ) ) {
			define( 'WPGRAPHQL_TAXQUERY_VERSION', '0.1.0' );
		}

		// Plugin Folder Path.
		if ( ! defined( 'WPGRAPHQL_TAXQUERY_PLUGIN_DIR' ) ) {
			define( 'WPGRAPHQL_TAXQUERY_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );
		}

		// Plugin Folder URL.
		if ( ! defined( 'WPGRAPHQL_TAXQUERY_PLUGIN_URL' ) ) {
			define( 'WPGRAPHQL_TAXQUERY_PLUGIN_URL', plugin_dir_url( __FILE__ ) );
		}

		// Plugin Root File.
		if ( ! defined( 'WPGRAPHQL_TAXQUERY_PLUGIN_FILE' ) ) {
			define( 'WPGRAPHQL_TAXQUERY_PLUGIN_FILE', __FILE__ );
		}

	}

	/**
	 * Include required files.
	 *
	 * Uses composer's autoload
	 *
	 * @access private
	 * @since 0.0.1
	 * @return void
	 */
	private function includes() {
		// Autoload Required Classes
		require_once( WPGRAPHQL_TAXQUERY_PLUGIN_DIR . 'vendor/autoload.php' );
	}

	/**
	 * add_input_fields
	 *
	 * This adds the taxQuery input fields
	 *
	 * @param array        $fields
	 * @param string       $type_name
	 * @param array        $config
	 * @param TypeRegistry $type_registry
	 *
	 * @return mixed
	 * @since 0.0.1
	 * @throws \Exception
	 */
	public function add_input_fields( $fields, $type_name, $config, $type_registry ) {

		if ( isset( $config['queryClass'] ) && 'WP_Query' === $config['queryClass'] ) {
			$fields['taxQuery'] = [
				'type' => 'TaxQuery'
			];
		}

		return $fields;
	}

	/**
	 * @param TypeRegistry $type_registry
	 *
	 * @throws \Exception
	 */
	public function register_types( TypeRegistry $type_registry ) {

		$type_registry->register_enum_type( 'TaxQueryField', [
			'description' => __( 'Which field to select taxonomy term by. Default value is "term_id"', 'wp-graphql' ),
			'values'      => [
				'ID'          => [
					'name'  => 'ID',
					'value' => 'term_id',
				],
				'NAME'        => [
					'name'  => 'NAME',
					'value' => 'name',
				],
				'SLUG'        => [
					'name'  => 'SLUG',
					'value' => 'slug',
				],
				'TAXONOMY_ID' => [
					'name'  => 'TAXONOMY_ID',
					'value' => 'term_taxonomy_id',
				],
			],
		] );

		$type_registry->register_enum_type( 'TaxQueryOperator', [
			'values' => [
				'IN'         => [
					'name'  => 'IN',
					'value' => 'IN',
				],
				'NOT_IN'     => [
					'name'  => 'NOT_IN',
					'value' => 'NOT IN',
				],
				'AND'        => [
					'name'  => 'AND',
					'value' => 'AND',
				],
				'EXISTS'     => [
					'name'  => 'EXISTS',
					'value' => 'EXISTS',
				],
				'NOT_EXISTS' => [
					'name'  => 'NOT_EXISTS',
					'value' => 'NOT EXISTS',
				],
			],
		] );

		$type_registry->register_input_type( 'TaxArray', [
			'fields' => [
				'taxonomy'        => [
					'type' => 'TaxonomyEnum',
				],
				'field'           => [
					'type' => 'TaxQueryField',
				],
				'terms'           => [
					'type'        => [ 'list_of' => 'String' ],
					'description' => __( 'A list of term slugs', 'wp-graphql' ),
				],
				'includeChildren' => [
					'type'        => 'Boolean',
					'description' => __( 'Whether or not to include children for hierarchical taxonomies. Defaults to false to improve performance (note that this is opposite of the default for WP_Query).', 'wp-graphql' ),
				],
				'operator'        => [
					'type' => 'TaxQueryOperator',
				],
			]
		] );

		$type_registry->register_input_type( 'TaxQuery', [
			'description' => __( 'Query objects based on taxonomy parameters', 'wp-graphql' ),
			'fields'      => [
				'relation' => [
					'type' => 'RelationEnum',
				],
				'taxArray' => [
					'type' => [
						'list_of' => 'TaxArray',
					],
				],
			],
		] );
	}

	/**
	 * map_input_fields
	 *
	 * This maps the taxQuery input fields to the WP_Query
	 *
	 * @param $query_args
	 * @param $input_args
	 *
	 * @return mixed
	 * @since 0.0.1
	 */
	public function map_input_fields( $query_args, $input_args ) {

		/**
		 * TaxQuery $args
		 * This maps the GraphQL taxQuery input to the WP_Query tax_query format
		 * @since 0.0.5
		 */
		$tax_query = null;
		if ( ! empty( $input_args['taxQuery'] ) ) {

			// Get the taxQuery input
			$tax_query = $input_args['taxQuery'];

			// If the taxArray was entered
			if ( ! empty( $tax_query['taxArray'] ) && is_array( $tax_query['taxArray'] ) ) {

				// If less than 2 taxArray objects were passed through, we don't need the "relation" field
				// to be passed to WP_Query, so we'll unset it now
				if ( 2 > count( $tax_query['taxArray'] ) ) {
					unset( $tax_query['relation'] );
				}

				// Loop through the taxArray
				foreach ( $tax_query['taxArray'] as $tax_array_key => $value ) {

					// If the "field" option was selected to be "term_id" or "term_taxonomy_id" we need to convert
					// the values of the "terms" array from strings to integers.
					if ( ! empty( $value['terms'] ) ) {
						if ( ! empty( $value['field'] ) && ( 'term_id' === $value['field'] || 'term_taxonomy_id' === $value['field'] ) ) {
							$formatted_terms = [];
							foreach ( $value['terms'] as $term ) {
								$formatted_terms[] = intval( $term );
							}
							$value['terms'] = $formatted_terms;
						}
					}

					// Make "include_children => false" for performance reasons unless
					// it is specifically requested (but one really shouldn't). See
					// https://vip.wordpress.com/documentation/term-queries-should-consider-include_children-false/
					$value['include_children'] = false;
					if ( isset( $value['includeChildren'] ) ) {
						$value['include_children'] = $value['includeChildren'];
						unset( $value['includeChildren'] );
					}

					$tax_query[ $tax_array_key ] = $value;
				}
			}
			unset( $tax_query['taxArray'] );
		} // End if().

		if ( ! empty( $tax_query ) ) {
			$query_args['tax_query'] = $tax_query;
		}

		unset( $query_args['taxQuery'] );

		/**
		 * Retrun the $query_args
		 * @since 0.0.1
		 */
		return $query_args;

	}

}

/**
 * Instantiate the TaxQuery class on graphql_init
 * @return TaxQuery
 */
function graphql_init_tax_query() {
	return new TaxQuery();
}

add_action( 'graphql_register_types', '\WPGraphql\graphql_init_tax_query' );