<?php
/**
* Core 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
*/
require ABSPATH . WPINC . '/class-wp-metadata-lazyloader.php';
/**
* Adds metadata for the specified object.
*
* @since 2.9.0
*
* @global wpdb $wpdb WordPress database abstraction object.
*
* @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
* or any other object type with an associated meta table.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. Must be serializable if non-scalar.
* @param bool $unique Optional. 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. Default false.
* @return int|false The meta ID on success, false on failure.
*/
function add_metadata( $meta_type, $object_id, $meta_key, $meta_value, $unique = false ) {
global $wpdb;
if ( ! $meta_type || ! $meta_key || ! is_numeric( $object_id ) ) {
return false;
}
$object_id = absint( $object_id );
if ( ! $object_id ) {
return false;
}
$table = _get_meta_table( $meta_type );
if ( ! $table ) {
return false;
}
$meta_subtype = get_object_subtype( $meta_type, $object_id );
$column = sanitize_key( $meta_type . '_id' );
// expected_slashed ($meta_key)
$meta_key = wp_unslash( $meta_key );
$meta_value = wp_unslash( $meta_value );
$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type, $meta_subtype );
/**
* Short-circuits adding metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
* Returning a non-null value will effectively short-circuit the function.
*
* Possible hook names include:
*
* - `add_post_metadata`
* - `add_comment_metadata`
* - `add_term_metadata`
* - `add_user_metadata`
*
* @since 3.1.0
*
* @param null|bool $check Whether to allow adding metadata for the given type.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. Must be serializable if non-scalar.
* @param bool $unique Whether the specified meta key should be unique for the object.
*/
$check = apply_filters( "add_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $unique );
if ( null !== $check ) {
return $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( $meta_value );
/**
* Fires immediately before meta of a specific type is added.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `add_post_meta`
* - `add_comment_meta`
* - `add_term_meta`
* - `add_user_meta`
*
* @since 3.1.0
*
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action( "add_{$meta_type}_meta", $object_id, $meta_key, $_meta_value );
$result = $wpdb->insert(
$table,
array(
$column => $object_id,
'meta_key' => $meta_key,
'meta_value' => $meta_value,
)
);
if ( ! $result ) {
return false;
}
$mid = (int) $wpdb->insert_id;
wp_cache_delete( $object_id, $meta_type . '_meta' );
/**
* Fires immediately after meta of a specific type is added.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `added_post_meta`
* - `added_comment_meta`
* - `added_term_meta`
* - `added_user_meta`
*
* @since 2.9.0
*
* @param int $mid The meta ID after successful update.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action( "added_{$meta_type}_meta", $mid, $object_id, $meta_key, $_meta_value );
return $mid;
}
/**
* Updates 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
*
* @global wpdb $wpdb WordPress database abstraction object.
*
* @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
* or any other object type with an associated meta table.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. Must be serializable if non-scalar.
* @param mixed $prev_value Optional. Previous value to check before updating.
* If specified, only update existing metadata entries with
* this value. Otherwise, update all entries. Default empty string.
* @return int|bool The new meta field ID if a field with the given key didn't exist
* and was therefore added, true on successful update,
* false on failure or if the value passed to the function
* is the same as the one that is already in the database.
*/
function update_metadata( $meta_type, $object_id, $meta_key, $meta_value, $prev_value = '' ) {
global $wpdb;
if ( ! $meta_type || ! $meta_key || ! is_numeric( $object_id ) ) {
return false;
}
$object_id = absint( $object_id );
if ( ! $object_id ) {
return false;
}
$table = _get_meta_table( $meta_type );
if ( ! $table ) {
return false;
}
$meta_subtype = get_object_subtype( $meta_type, $object_id );
$column = sanitize_key( $meta_type . '_id' );
$id_column = ( 'user' === $meta_type ) ? 'umeta_id' : 'meta_id';
// expected_slashed ($meta_key)
$raw_meta_key = $meta_key;
$meta_key = wp_unslash( $meta_key );
$passed_value = $meta_value;
$meta_value = wp_unslash( $meta_value );
$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type, $meta_subtype );
/**
* Short-circuits updating metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
* Returning a non-null value will effectively short-circuit the function.
*
* Possible hook names include:
*
* - `update_post_metadata`
* - `update_comment_metadata`
* - `update_term_metadata`
* - `update_user_metadata`
*
* @since 3.1.0
*
* @param null|bool $check Whether to allow updating metadata for the given type.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. Must be serializable if non-scalar.
* @param mixed $prev_value Optional. Previous value to check before updating.
* If specified, only update existing metadata entries with
* this value. Otherwise, update all entries.
*/
$check = apply_filters( "update_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $prev_value );
if ( null !== $check ) {
return (bool) $check;
}
// 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_raw( $meta_type, $object_id, $meta_key );
if ( is_countable( $old_value ) && count( $old_value ) === 1 ) {
if ( $old_value[0] === $meta_value ) {
return false;
}
}
}
$meta_ids = $wpdb->get_col( $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s AND $column = %d", $meta_key, $object_id ) );
if ( empty( $meta_ids ) ) {
return add_metadata( $meta_type, $object_id, $raw_meta_key, $passed_value );
}
$_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;
}
foreach ( $meta_ids as $meta_id ) {
/**
* Fires immediately before updating metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `update_post_meta`
* - `update_comment_meta`
* - `update_term_meta`
* - `update_user_meta`
*
* @since 2.9.0
*
* @param int $meta_id ID of the metadata entry to update.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
if ( 'post' === $meta_type ) {
/**
* Fires immediately before updating a post's metadata.
*
* @since 2.9.0
*
* @param int $meta_id ID of metadata entry to update.
* @param int $object_id Post ID.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. This will be a PHP-serialized string representation of the value
* if the value is an array, an object, or itself a PHP-serialized string.
*/
do_action( 'update_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
}
}
$result = $wpdb->update( $table, $data, $where );
if ( ! $result ) {
return false;
}
wp_cache_delete( $object_id, $meta_type . '_meta' );
foreach ( $meta_ids as $meta_id ) {
/**
* Fires immediately after updating metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `updated_post_meta`
* - `updated_comment_meta`
* - `updated_term_meta`
* - `updated_user_meta`
*
* @since 2.9.0
*
* @param int $meta_id ID of updated metadata entry.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
if ( 'post' === $meta_type ) {
/**
* Fires immediately after updating a post's metadata.
*
* @since 2.9.0
*
* @param int $meta_id ID of updated metadata entry.
* @param int $object_id Post ID.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. This will be a PHP-serialized string representation of the value
* if the value is an array, an object, or itself a PHP-serialized string.
*/
do_action( 'updated_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
}
}
return true;
}
/**
* Deletes metadata for the specified object.
*
* @since 2.9.0
*
* @global wpdb $wpdb WordPress database abstraction object.
*
* @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
* or any other object type with an associated meta table.
* @param int $object_id ID of the