<?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);

$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );

$check = apply_filters( "add_{$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);

$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );

$check = apply_filters( "update_{$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 $type Type of meta

* @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, $type, $primary_table, $primary_id_column, $context = null ) {

global $wpdb;

if ( ! $meta_table = _get_meta_table( $type ) )

return false;

$meta_id_column = esc_sql( $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, $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;

}

/**

* Determine whether a meta key is protected

*

* @since 3.1.3

*

* @param string $meta_key Meta key

* @return bool True if the key is protected, false otherwise.

*/

function is_protected_meta( $meta_key, $meta_type = null ) {

$protected = ( '_' == $meta_key[0] );

return apply_filters( 'is_protected_meta', $protected, $meta_key, $meta_type );

}

/**

* Sanitize meta value

*

* @since 3.1.3

*

* @param string $meta_key Meta key

* @param mixed $meta_value Meta value to sanitize

* @param string $meta_type Type of meta

* @return mixed Sanitized $meta_value

*/

function sanitize_meta( $meta_key, $meta_value, $meta_type = null ) {

return apply_filters( 'sanitize_meta', $meta_value, $meta_key, $meta_type );

}

?>