Wordlift_Cached_Post_Converter

Complexity

Total Complexity

13

Size/Duplication

Total Lines	217
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	3

Importance

Changes

0

9 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	10	1
B	init_hooks()	0	29	1
B	convert()	0	29	2
A	get_cache()	0	20	4
A	set_cache()	0	10	1
A	save_post()	0	5	1
A	changed_post_meta()	0	5	1
A	update_option_wl_general_settings()	0	5	1
A	relation_changed()	0	5	1

<?php
/**
 * Converters: Cache Post Converter
 *
 * The Cached Post Converter looks for cached copies of converter results before
 * actually calling the underlying {@link Wordlift_Post_Converter} (injected
 * via the constructor).
 *
 * @since      3.16.0
 * @package    Wordlift
 * @subpackage Wordlift/includes/cache
 */

/**
 * Define the {@link Wordlift_Cached_Post_Converter} class.
 *
 * @since 3.16.0
 */
class Wordlift_Cached_Post_Converter implements Wordlift_Post_Converter {

	/**
	 * A {@link Wordlift_Post_Converter} instance.
	 *
	 * @since 3.16.0
	 *
	 * @var \Wordlift_Post_Converter $converter A {@link Wordlift_Post_Converter} instance.
	 */
	private $converter;

	/**
	 * A {@link Wordlift_Log_Service} instance.
	 *
	 * @since 3.16.0
	 *
	 * @var Wordlift_Log_Service \$log A {@link Wordlift_Log_Service} instance.
	 */
	private $log;

	/**
	 * @var Wordlift_Cache_Service
	 */
	private $cache_service;

	/**
	 * Wordlift_Cached_Post_Converter constructor.
	 *
	 * @param \Wordlift_Post_Converter $converter
	 * @param \Wordlift_Cache_Service  $cache_service
	 */
	public function __construct( $converter, $cache_service ) {

		$this->log = Wordlift_Log_Service::get_logger( get_class() );

		$this->converter     = $converter;
		$this->cache_service = $cache_service;

		$this->init_hooks();

	}

	/**
	 * Hooks to catch post/post meta changes in order to invalidate the cache.
	 *
	 * @since 3.16.0
	 */
	private function init_hooks() {

		// Hook on post save to flush relevant cache.
		add_action( 'save_post', array( $this, 'save_post' ) );

		add_action( 'added_post_meta', array(
			$this,
			'changed_post_meta',
		), 10, 2 );
		add_action( 'updated_post_meta', array(
			$this,
			'changed_post_meta',
		), 10, 2 );
		add_action( 'deleted_post_meta', array(
			$this,
			'changed_post_meta',
		), 10, 2 );

		// Flush cache when wordlift settings were updated.
		add_action( 'update_option_wl_general_settings', array(
			$this,
			'update_option_wl_general_settings',
		) );

		// Invalid cache on relationship change.
		add_action( 'wl_relation_added', array( $this, 'relation_changed' ) );
		add_action( 'wl_relation_deleted', array( $this, 'relation_changed' ) );

	}

	/**
	 * @inheritdoc
	 */
	public function convert( $post_id, &$references = array(), &$cache = false ) {

		$this->log->trace( "Converting post $post_id..." );

		// Try to get a cached result.
		$contents = $this->get_cache( $post_id, $references );

		// Return the cached contents if any.
		if ( false !== $contents ) {
			$this->log->debug( "Cached contents found for post $post_id." );

			// Inform the caller that this is cached result.
			$cache = true;

			// Return the contents.
			return $contents;
		}

		$cache = false;

		// Convert the the post.
		$jsonld = $this->converter->convert( $post_id, $references );

		// Cache the results.
		$this->set_cache( $post_id, $references, $jsonld );

		// Finally return the JSON-LD.
		return $jsonld;
	}

	/**
	 * Try to get the cached contents.
	 *
	 * @since 3.16.0
	 *
	 * @param int   $post_id    The {@link WP_Post} id.
	 * @param array $references The referenced posts.
	 *
	 * @return mixed|bool The cached contents or false if the cached isn't found.
	 */
	private function get_cache( $post_id, &$references = array() ) {

		$this->log->trace( "Getting cached contents for post $post_id..." );

		// Get the cache.
		$contents = $this->cache_service->get_cache( $post_id );

		// Bail out if we don't have cached contents or the cached contents are
		// invalid.
		if ( false === $contents || ! isset( $contents['jsonld'] ) || ! isset( $contents['references'] ) ) {
			$this->log->debug( "Cached contents for post $post_id not found." );

			return false;
		}

		// Remap the cache.
		$references = $contents['references'];

		return $contents['jsonld'];
	}

	/**
	 * Set the cache with the provided results.
	 *
	 * The function will prepare the provided results and will ask the {@link Wordlift_Cache_Service}
	 * to cache them.
	 *
	 * @since 3.16.0
	 *
	 * @param int   $post_id    The {@link WP_Post} id.
	 * @param array $references An array of references.
	 * @param array $jsonld     A JSON-LD structure.
	 */
	private function set_cache( $post_id, $references, $jsonld ) {

		$this->log->trace( "Caching result for post $post_id..." );

		$this->cache_service->set_cache( $post_id, array(
			'references' => $references,
			'jsonld'     => $jsonld,
		) );

	}

	/**
	 * Hook to 'save_post', will invalidate the cache for that post.
	 *
	 * @since 3.16.0
	 *
	 * @param int $post_id The {@link WP_Post} id.
	 */
	public function save_post( $post_id ) {
		$this->log->trace( "Post $post_id saved, invalidating cache..." );

		$this->cache_service->delete_cache( $post_id );
	}

	/**
	 * Hook to meta changed for a {@link WP_Post}, will cause the cause to
	 * invalidate.
	 *
	 * @since 3.16.0
	 *
	 * @param int $id      The {@link WP_Post} meta id.
	 * @param int $post_id The {@link WP_Post} id.
	 */
	public function changed_post_meta( $id, $post_id ) {
		$this->log->trace( "Post $post_id meta changed, invalidating cache..." );

		$this->cache_service->delete_cache( $post_id );
	}

	/**
	 * Hook to WordLift's options changes, will flush the cache.
	 *
	 * @since 3.16.0
	 */
	public function update_option_wl_general_settings() {
		$this->log->trace( "WordLift options changed, flushing cache..." );

		$this->cache_service->flush();
	}

	/**
	 * Hook to WordLift's post/entity relation changes, will invalidate the cache.
	 *
	 * @since 3.16.0
	 *
	 * @param int $post_id The {@link WP_Post} id.
	 */
	public function relation_changed( $post_id ) {
		$this->log->trace( "Post $post_id relations changed, invalidating cache..." );

		$this->cache_service->delete_cache( $post_id );
	}

}