<?php
/**
* Metadata API
*
* Functions for retrieving and manipulating metadata of various WordPress object types. Metadata
* for an object is a represented by a simple key-value pair. Objects may contain multiple
* metadata entries that share the same key and differ only in their value.
*
* @package WordPress
* @subpackage Meta
* @since 2.9.0
*/
/**
* Add metadata for the specified object.
*
* @since 2.9.0
* @uses $wpdb WordPress database object for queries.
* @uses do_action() Calls 'added_{$meta_type}_meta' with meta_id of added metadata entry,
* object ID, meta key, and meta value
*
* @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
* @param int $object_id ID of the object metadata is for
* @param string $meta_key Metadata key
* @param string $meta_value Metadata value
* @param bool $unique Optional, default is false. Whether the specified metadata key should be
* unique for the object. If true, and the object already has a value for the specified
* metadata key, no change will be made
* @return bool True on successful update, false on failure.
*/
function add_metadata($meta_type, $object_id, $meta_key, $meta_value, $unique = false) {
if ( !$meta_type || !$meta_key )
return false;
if ( !$object_id = absint($object_id) )
return false;
if ( ! $table = _get_meta_table($meta_type) )
return false;
global $wpdb;
$column = esc_sql($meta_type . '_id');
// expected_slashed ($meta_key)
$meta_key = stripslashes($meta_key);
$meta_value = stripslashes_deep($meta_value);
$check = apply_filters( "add_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $unique );
if ( null !== $check )
return (bool) $check;
if ( $unique && $wpdb->get_var( $wpdb->prepare(
"SELECT COUNT(*) FROM $table WHERE meta_key = %s AND $column = %d",
$meta_key, $object_id ) ) )
return false;
$_meta_value = $meta_value;
$meta_value = maybe_serialize( $meta_value );
do_action( "add_{$meta_type}_meta", $object_id, $meta_key, $_meta_value );
$wpdb->insert( $table, array(
$column => $object_id,
'meta_key' => $meta_key,
'meta_value' => $meta_value
) );
wp_cache_delete($object_id, $meta_type . '_meta');
// users cache stores usermeta that must be cleared.
if ( 'user' == $meta_type )
clean_user_cache($object_id);
do_action( "added_{$meta_type}_meta", $wpdb->insert_id, $object_id, $meta_key, $_meta_value );
return true;
}
/**
* Update metadata for the specified object. If no value already exists for the specified object
* ID and metadata key, the metadata will be added.
*
* @since 2.9.0
* @uses $wpdb WordPress database object for queries.
* @uses do_action() Calls 'update_{$meta_type}_meta' before updating metadata with meta_id of
* metadata entry to update, object ID, meta key, and meta value
* @uses do_action() Calls 'updated_{$meta_type}_meta' after updating metadata with meta_id of
* updated metadata entry, object ID, meta key, and meta value
*
* @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
* @param int $object_id ID of the object metadata is for
* @param string $meta_key Metadata key
* @param string $meta_value Metadata value
* @param string $prev_value Optional. If specified, only update existing metadata entries with
* the specified value. Otherwise, update all entries.
* @return bool True on successful update, false on failure.
*/
function update_metadata($meta_type, $object_id, $meta_key, $meta_value, $prev_value = '') {
if ( !$meta_type || !$meta_key )
return false;
if ( !$object_id = absint($object_id) )
return false;
if ( ! $table = _get_meta_table($meta_type) )
return false;
global $wpdb;
$column = esc_sql($meta_type . '_id');
$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
// expected_slashed ($meta_key)
$meta_key = stripslashes($meta_key);
$meta_value = stripslashes_deep($meta_value);
$check = apply_filters( "update_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $prev_value );
if ( null !== $check )
return (bool) $check;
if ( ! $meta_id = $wpdb->get_var( $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s AND $column = %d", $meta_key, $object_id ) ) )
return add_metadata($meta_type, $object_id, $meta_key, $meta_value);
// Compare existing value to new value if no prev value given and the key exists only once.
if ( empty($prev_value) ) {
$old_value = get_metadata($meta_type, $object_id, $meta_key);
if ( count($old_value) == 1 ) {
if ( $old_value[0] === $meta_value )
return false;
}
}
$_meta_value = $meta_value;
$meta_value = maybe_serialize( $meta_value );
$data = compact( 'meta_value' );
$where = array( $column => $object_id, 'meta_key' => $meta_key );
if ( !empty( $prev_value ) ) {
$prev_value = maybe_serialize($prev_value);
$where['meta_value'] = $prev_value;
}
do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
$wpdb->update( $table, $data, $where );
wp_cache_delete($object_id, $meta_type . '_meta');
// users cache stores usermeta that must be cleared.
if ( 'user' == $meta_type )
clean_user_cache($object_id);
do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
return true;
}
/**
* Delete metadata for the specified object.
*
* @since 2.9.0
* @uses $wpdb WordPress database object for queries.
* @uses do_action() Calls 'deleted_{$meta_type}_meta' after deleting with meta_id of
* deleted metadata entries, object ID, meta key, and meta value
*
* @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
* @param int $object_id ID of the object metadata is for
* @param string $meta_key Metadata key
* @param string $meta_value Optional. Metadata value. If specified, only delete metadata entries
* with this value. Otherwise, delete all entries with the specified meta_key.
* @param bool $delete_all Optional, default is false. If true, delete matching metadata entries
* for all objects, ignoring the specified object_id. Otherwise, only delete matching
* metadata entries for the specified object_id.
* @return bool True on successful delete, false on failure.
*/
function delete_metadata($meta_type, $object_id, $meta_key, $meta_value = '', $delete_all = false) {
if ( !$meta_type || !$meta_key )
return false;
if ( (!$object_id = absint($object_id)) && !$delete_all )
return false;
if ( ! $table = _get_meta_table($meta_type) )
return false;
global $wpdb;
$type_column = esc_sql($meta_type . '_id');
$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
// expected_slashed ($meta_key)
$meta_key = stripslashes($meta_key);
$meta_value = stripslashes_deep($meta_value);
$check = apply_filters( "delete_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $delete_all );
if ( null !== $check )
return (bool) $check;
$_meta_value = $meta_value;
$meta_value = maybe_serialize( $meta_value );
$query = $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s", $meta_key );
if ( !$delete_all )
$query .= $wpdb->prepare(" AND $type_column = %d", $object_id );
if ( $meta_value )
$query .= $wpdb->prepare(" AND meta_value = %s", $meta_value );
$meta_ids = $wpdb->get_col( $query );
if ( !count( $meta_ids ) )
return false;
do_action( "delete_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value );
$query = "DELETE FROM $table WHERE $id_column IN( " . implode( ',', $meta_ids ) . " )";
$count = $wpdb->query($query);
if ( !$count )
return false;
wp_cache_delete($object_id, $meta_type . '_meta');
// users cache stores usermeta that must be cleared.
if ( 'user' == $meta_type )
clean_user_cache($object_id);
do_action( "deleted_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value );
return true;
}
/**
* Retrieve metadata for the specified object.
*
* @since 2.9.0
*
* @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
* @param int $object_id ID of the object metadata is for
* @param string $meta_key Optional. Metadata key. If not specified, retrieve all metadata for
* the specified object.
* @param bool $single Optional, default is false. If true, return only the first value of the
* specified meta_key. This parameter has no effect if meta_key is not specified.
* @return string|array Single metadata value, or array of values
*/
function get_metadata($meta_type, $object_id, $meta_key = '', $single = false) {
if ( !$meta_type )
return false;
if ( !$object_id = absint($object_id) )
return false;
$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, $single );
if ( null !== $check ) {
if ( $single && is_array( $check ) )
return $check[0];
else
return $check;
}
$meta_cache = wp_cache_get($object_id, $meta_type . '_meta');
if ( !$meta_cache ) {
$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
$meta_cache = $meta_cache[$object_id];
}
if ( !$meta_key )
return $meta_cache;
if ( isset($meta_cache[$meta_key]) ) {
if ( $single )
return maybe_unserialize( $meta_cache[$meta_key][0] );
else
return array_map('maybe_unserialize', $meta_cache[$meta_key]);
}
if ($single)
return '';
else
return array();
}
/**
* Update the metadata cache for the specified objects.
*
* @since 2.9.0
* @uses $wpdb WordPress database object for queries.
*
* @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
* @param int|array $object_ids array or comma delimited list of object IDs to update cache for
* @return mixed Metadata cache for the specified objects, or false on failure.
*/
function update_meta_cache($meta_type, $object_ids) {
if ( empty( $meta_type ) || empty( $object_ids ) )
return false;
if ( ! $table = _get_meta_table($meta_type) )
return false;
$column = esc_sql($meta_type . '_id');
global $wpdb;
if ( !is_array($object_ids) ) {
$object_ids = preg_replace('|[^0-9,]|', '', $object_ids);
$object_ids = explode(',', $object_ids);
}
$object_ids = array_map('intval', $object_ids);
$cache_key = $meta_type . '_meta';
$ids = array();
$cache = array();
foreach ( $object_ids as $id ) {
$cached_object = wp_cache_get( $id, $cache_key );
if ( false === $cached_object )
$ids[] = $id;
else
$cache[$id] = $cached_object;
}
if ( empty( $ids ) )
return $cache;
// Get meta info
$id_list = join(',', $ids);
$meta_list = $wpdb->get_results( $wpdb->prepare("SELECT $column, meta_key, meta_value FROM $table WHERE $column IN ($id_list)",
$meta_type), ARRAY_A );
if ( !empty($meta_list) ) {
foreach ( $meta_list as $metarow) {
$mpid = intval($metarow[$column]);
$mkey = $metarow['meta_key'];
$mval = $metarow['meta_value'];
// Force subkeys to be array type:
if ( !isset($cache[$mpid]) || !is_array($cache[$mpid]) )
$cache[$mpid] = array();
if ( !isset($cache[$mpid][$mkey]) || !is_array($cache[$mpid][$mkey]) )
$cache[$mpid][$mkey] = array();
// Add a value to the current pid/key:
$cache[$mpid][$mkey][] = $mval;
}
}
foreach ( $ids as $id ) {
if ( ! isset($cache[$id]) )
$cache[$id] = array();
wp_cache_add( $id, $cache[$id], $cache_key );
}
return $cache;
}
/**
* Given a meta query, generates SQL clauses to be appended to a main query
*
* @since 3.1.0
* @access private
*
* @param array $meta_query List of metadata queries. A single query is an associative array:
* - 'key' string The meta key
* - 'value' string|array The meta value
* - 'compare' (optional) string How to compare the key to the value.
* Possible values: '=', '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN'.
* Default: '='
* - 'type' string (optional) The type of the value.
* Possible values: 'NUMERIC', 'BINARY', 'CHAR', 'DATE', 'DATETIME', 'DECIMAL', 'SIGNED', 'TIME', 'UNSIGNED'.
* Default: 'CHAR'
*
* @param string $meta_type
* @param string $primary_table
* @param string $primary_id_column
* @param object $context (optional) The main query object
* @return array( 'join' => $join_sql, 'where' => $where_sql )
*/
function _get_meta_sql( $meta_query, $meta_type, $primary_table, $primary_id_column, $context = null ) {
global $wpdb;
if ( ! $meta_table = _get_meta_table( $meta_type ) )
return false;
$meta_id_column = esc_sql( $meta_type . '_id' );
$join = '';
$where = '';
$i = 0;
foreach ( $meta_query as $q ) {
$meta_key = isset( $q['key'] ) ? trim( $q['key'] ) : '';
$meta_value = isset( $q['value'] ) ? $q['value'] : '';
$meta_compare = isset( $q['compare'] ) ? strtoupper( $q['compare'] ) : '=';
$meta_type = isset( $q['type'] ) ? strtoupper( $q['type'] ) : 'CHAR';
if ( ! in_array( $meta_compare, array( '=', '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ) ) )
$meta_compare = '=';
if ( 'NUMERIC' == $meta_type )
$meta_type = 'SIGNED';
elseif ( ! in_array( $meta_type, array( 'BINARY', 'CHAR', 'DATE', 'DATETIME', 'DECIMAL', 'SIGNED', 'TIME', 'UNSIGNED' ) ) )
$meta_type = 'CHAR';
if ( empty( $meta_key ) && empty( $meta_value ) )
continue;
$alias = $i ? 'mt' . $i : $meta_table;
$join .= "\nINNER JOIN $meta_table";
$join .= $i ? " AS $alias" : '';
$join .= " ON ($primary_table.$primary_id_column = $alias.$meta_id_column)";
$i++;
if ( !empty( $meta_key ) )
$where .= $wpdb->prepare( " AND $alias.meta_key = %s", $meta_key );
if ( in_array( $meta_compare, array( 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ) ) ) {
if ( ! is_array( $meta_value ) )
$meta_value = preg_split( '/[,\s]+/', $meta_value );
} else {
$meta_value = trim( $meta_value );
}
if ( empty( $meta_value ) )
continue;
if ( 'IN' == substr( $meta_compare, -2) ) {
$meta_compare_string = '(' . substr( str_repeat( ',%s', count( $meta_value ) ), 1 ) . ')';
} elseif ( 'BETWEEN' == substr( $meta_compare, -7) ) {
$meta_value = array_slice( $meta_value, 0, 2 );
$meta_compare_string = '%s AND %s';
} elseif ( 'LIKE' == substr( $meta_compare, -4 ) ) {
$meta_value = '%' . like_escape( $meta_value ) . '%';
$meta_compare_string = '%s';
} else {
$meta_compare_string = '%s';
}
// @todo Temporary hack to support empty values. Do not use outside of core.
if ( '_wp_zero_value' == $meta_value )
$meta_value = 0;
$where .= $wpdb->prepare( " AND CAST($alias.meta_value AS {$meta_type}) {$meta_compare} {$meta_compare_string}", $meta_value );
}
return apply_filters_ref_array( 'get_meta_sql', array( compact( 'join', 'where' ), $meta_query, $meta_type, $primary_table, $primary_id_column, &$context ) );
}
/**
* Populates the $meta_query property
*
* @access private
* @since 3.1.0
*
* @param array $qv The query variables
*/
function _parse_meta_query( &$qv ) {
$meta_query = array();
// Simple query needs to be first for orderby=meta_value to work correctly
foreach ( array( 'key', 'value', 'compare', 'type' ) as $key ) {
if ( !empty( $qv[ "meta_$key" ] ) )
$meta_query[0][ $key ] = $qv[ "meta_$key" ];
}
if ( !empty( $qv['meta_query'] ) && is_array( $qv['meta_query'] ) ) {
$meta_query = array_merge( $meta_query, $qv['meta_query'] );
}
$qv['meta_query'] = $meta_query;
}
/**
* Retrieve the name of the metadata table for the specified object type.
*
* @since 2.9.0
* @uses $wpdb WordPress database object for queries.
*
* @param string $type Type of object to get metadata table for (e.g., comment, post, or user)
* @return mixed Metadata table name, or false if no metadata table exists
*/
function _get_meta_table($type) {
global $wpdb;
$table_name = $type . 'meta';
if ( empty($wpdb->$table_name) )
return false;
return $wpdb->$table_name;
}
?>