New Abstract WC_Data Class

includes/abstracts/abstract-wc-data.php

@@ -0,0 +1,319 @@
+<?php
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
+
+/**
+* Abstract WC Data Class
+*
+* Implemented by classes using the same CRUD(s) pattern.
+*
+* @version  2.7.0
+* @package  WooCommerce/Abstracts
+* @category Abstract Class
+* @author   WooThemes
+*/
+abstract class WC_Data {
+
+	/**
+	 * Stores meta in cache for future reads.
+	 * A group must be set to to enable caching.
+	 * @var string
+	 */
+	protected $_cache_group = '';
+
+	/**
+	 * Meta type. This should match up with
+	 * the types avaiable at https://codex.wordpress.org/Function_Reference/add_metadata.
+	 * WP defines 'post', 'user', 'comment', and 'term'.
+	 */
+	protected $_meta_type = 'post';
+
+	/**
+	 * This only needs set if you are using a custom metadata type (for example payment tokens.
+	 * This should be the name of the field your table uses for associating meta with objects.
+	 * For example, in payment_tokenmeta, this would be payment_token_id.
+	 * @var string
+	 */
+	protected $object_id_field_for_meta = '';
+
+	/**
+	 * Stores additonal meta data.
+	 * @var array
+	 */
+	protected $_meta_data = array();
+
+	/**
+	 * Internal meta keys we don't want exposed for the object.
+	 * @var array
+	 */
+	protected $_internal_meta_keys = array();
+
+	/**
+	 * Returns the unique ID for this object.
+	 * @return int
+	 */
+	abstract  public function get_id();
+
+	/**
+	 * Returns all data for this object.
+	 * @return array
+	 */
+	abstract public function get_data();
+
+	/**
+	 * Creates new object in the database.
+	 */
+	abstract public function create();
+
+	/**
+	 * Read object from the database.
+	 * @param int ID of the object to load.
+	 */
+	abstract public function read( $id );
+
+	/**
+	 * Updates object data in the database.
+	 */
+	abstract public function update();
+
+	/**
+	 * Updates object data in the database.
+	 */
+	abstract  public function delete();
+
+	/**
+	 * Save should create or update based on object existance.
+	 */
+	abstract public function save();
+
+	/**
+	 * Get All Meta Data
+	 * @return array
+	 */
+	public function get_meta_data() {
+		return $this->_meta_data;
+	}
+
+	/**
+	 * Internal meta keys we don't want exposed as part of meta_data. This is in
+	 * addition to all data props with _ prefix.
+	 * @return array()
+	 */
+	protected function prefix_key( $key ) {
+		return '_' === substr( $key, 0, 1 ) ? $key : '_' . $key;
+	}
+
+	/**
+	 * Internal meta keys we don't want exposed as part of meta_data. This is in
+	 * addition to all data props with _ prefix.
+	 * @return array()
+	 */
+	protected function get_internal_meta_keys() {
+		return array_merge( array_map( array( $this, 'prefix_key' ), array_keys( $this->_data ) ), $this->_internal_meta_keys );
+	}
+
+	/**
+	 * Get Meta Data by Key.
+	 * @param  string $key
+	 * @param  bool $single return first found meta with key, or all with $key
+	 * @return mixed
+	 */
+	public function get_meta( $key = '', $single = true ) {
+		$meta_ids = array_keys( wp_list_pluck( $this->_meta_data, 'key' ), $key );
+		$value    = '';
+
+		if ( $meta_ids ) {
+			if ( $single ) {
+				$value = $this->_meta_data[ current( $meta_ids ) ]->value;
+			} else {
+				$value = array_intersect_key( $this->_meta_data, $meta_ids );
+			}
+		}
+
+		return $value;
+	}
+
+	/**
+	 * Set all meta data from array.
+	 * @param array $data Key/Value pairs
+	 */
+	public function set_meta_data( $data ) {
+		if ( ! empty( $data ) && is_array( $data ) ) {
+			foreach ( $data as $meta_id => $meta ) {
+				$meta = (array) $meta;
+				if ( isset( $meta['key'], $meta['value'] ) ) {
+					$this->_meta_data[ $meta_id ] = (object) array(
+						'key'   => $meta['key'],
+						'value' => $meta['value'],
+					);
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * Add meta data.
+	 * @param array $key Meta key
+	 * @param array $value Meta value
+	 * @param array $unique Should this be a unique key?
+	 */
+	public function add_meta_data( $key, $value, $unique = false ) {
+		if ( $unique ) {
+			$meta_ids = array_keys( wp_list_pluck( $this->_meta_data, 'key' ), $key );
+			$this->_meta_data = array_diff_key( $this->_meta_data, array_fill_keys( $meta_ids, '' ) );
+		}
+		$this->_meta_data[ 'new-' . sizeof( $this->_meta_data ) ] = (object) array(
+			'key'   => $key,
+			'value' => $value,
+		);
+	}
+
+	/**
+	 * Update meta data by key or ID, if provided.
+	 * @param  string $key
+	 * @param  string $value
+	 * @param  int $meta_id
+	 */
+	public function update_meta_data( $key, $value, $meta_id = '' ) {
+		if ( $meta_id && isset( $this->_meta_data[ $meta_id ] ) ) {
+			$this->_meta_data[ $meta_id ] = (object) array(
+				'key'   => $key,
+				'value' => $value,
+			);
+		} else {
+			$this->add_meta_data( $key, $value, true );
+		}
+	}
+
+	/**
+	 * Delete meta data.
+	 * @param array $key Meta key
+	 */
+	public function delete_meta_data( $key ) {
+		$meta_ids         = array_keys( wp_list_pluck( $this->_meta_data, 'key' ), $key );
+		$this->_meta_data = array_diff_key( $this->_meta_data, array_fill_keys( $meta_ids, '' ) );
+	}
+
+	/**
+	 * Read Meta Data from the database. Ignore any internal properties.
+	 */
+	protected function read_meta_data() {
+		$this->_meta_data = array();
+		$cache_loaded     = false;
+
+		if ( ! $this->get_id() ) {
+			return;
+		}
+
+		if ( ! empty ( $this->_cache_group ) ) {
+			$cache_key   = WC_Cache_Helper::get_cache_prefix( $this->_cache_group ) . $this->get_id();
+			$cached_meta = wp_cache_get( $cache_key, $this->_cache_group );
+
+			if ( false !== $cached_meta ) {
+				$this->_meta_data = $cached_meta;
+				$cache_loaded = true;
+			}
+		}
+
+		if ( ! $cache_loaded ) {
+			global $wpdb;
+			$db_info = $this->_get_db_info();
+			$raw_meta_data = $wpdb->get_results( $wpdb->prepare( "
+				SELECT " . $db_info['meta_id_field'] . ", meta_key, meta_value
+				FROM " . $db_info['table'] . "
+				WHERE " . $db_info['object_id_field'] . " = %d ORDER BY meta_id
+			", $this->get_id() ) );
+
+			foreach ( $raw_meta_data as $meta ) {
+				if ( in_array( $meta->meta_key, $this->get_internal_meta_keys() ) ) {
+					continue;
+				}
+				$this->_meta_data[ $meta->meta_id ] = (object) array( 'key' => $meta->meta_key, 'value' => $meta->meta_value );
+			}
+
+			if ( ! empty ( $this->_cache_group ) ) {
+				wp_cache_set( $cache_key, $this->_meta_data, $this->_cache_group );
+			}
+		}
+	}
+
+	/**
+	 * Update Meta Data in the database.
+	 */
+	protected function save_meta_data() {
+		global $wpdb;
+		$db_info = $this->_get_db_info();
+		$all_meta_ids = array_map( 'absint', $wpdb->get_col( $wpdb->prepare( "
+			SELECT " . $db_info['meta_id_field'] . " FROM " . $db_info['table'] . "
+			WHERE " . $db_info['object_id_field'] . " = %d", $this->get_id() ) . "
+			AND meta_key NOT IN ('" . implode( "','", array_map( 'esc_sql', $this->get_internal_meta_keys() ) ) . "');
+		" ) );
+		$set_meta_ids = array();
+
+		foreach ( $this->_meta_data as $meta_id => $meta ) {
+			if ( 'new' === substr( $meta_id, 0, 3 ) ) {
+				$set_meta_ids[] = add_metadata( $this->_meta_type, $this->get_id(), $meta->key, $meta->value, false );
+			} else {
+				update_metadata_by_mid( $this->_meta_type, $meta_id, $meta->value, $meta->key );
+				$set_meta_ids[] = absint( $meta_id );
+			}
+		}
+
+		// Delete no longer set meta data
+		$delete_meta_ids = array_diff( $all_meta_ids, $set_meta_ids );
+
+		foreach ( $delete_meta_ids as $meta_id ) {
+			delete_metadata_by_mid( $this->_meta_type, $meta_id );
+		}
+
+		if ( ! empty ( $this->_cache_group ) ) {
+			WC_Cache_Helper::incr_cache_prefix( $this->_cache_group );
+		}
+		$this->read_meta_data();
+	}
+
+	/**
+	 * Table structure is slightly different between meta types, this function will return what we need to know.
+	 * @return array Array elements: table, object_id_field, meta_id_field
+	 */
+	private function _get_db_info() {
+		global $wpdb;
+
+		$object_id_field = '';
+		$meta_id_field   = 'meta_id'; // for some reason users calls this umeta_id so we need to track this as well.
+		$table           = $wpdb->prefix;
+		// If we are dealing with a type of metadata that is not a core type, the table should be prefixed.
+		if ( ! in_array( $this->_meta_type, array( 'post', 'user', 'comment', 'term' ) ) ) {
+			$table = 'woocommerce_';
+		}
+
+		$table = $this->_meta_type . 'meta';
+
+		// Figure out our field names.
+		if ( 'post' === $this->_meta_type ) {
+			$object_id_field = 'post_id';
+		} elseif ( 'user' === $this->_meta_type ) {
+			$object_id_field = 'user_id';
+			$meta_id_field   = 'umeta_id';
+		} else if ( 'comment' === $this->_meta_type ) {
+			$object_id_field = 'comment_id';
+		} else if ( 'term' === $this->_meta_data ) {
+			$object_id_field = 'term_id';
+		} else {
+			if ( ! empty ( $this->object_id_field_for_meta ) ) {
+				$object_id_field = $this->object_id_field_for_meta;
+			} else {
+				$object_id_field = 'post_id'; // default to post_id
+			}
+		}
+
+		return array(
+			'table'           => $table,
+			'object_id_field' => $object_id_field,
+			'meta_id_field'   => $meta_id_field,
+		);
+	}
+
+}