Changeset 56814 for trunk/src/wp-includes/option.php

Timestamp:

10/10/2023 09:35:09 AM (20 months ago)

Author:

spacedmonkey

Message:

Options, Meta APIs: Prevent unnecessary database updates caused by strict comparisons in update_network_option.

Previously, in the update_network_option function, strict comparisons between old and new values could erroneously trigger updates in cases where there was no actual change in values. Building upon the groundwork laid in #22192, this commit introduces the use of the _is_equal_database_value function to accurately compare values before initiating any database updates. This change ensures consistency between the behaviors of update_option and update_network_option.

Furthermore, we have incorporated similar workarounds that were previously implemented in [56717]. These changes ensure that the raw version of network option values is considered in the comparisons, enhancing the overall reliability of the update process.

Props mukesh27, flixos90, joemcgill, costdev, spacedmonkey.
Fixes #59360.

File:

• trunk/src/wp-includes/option.php (modified) (2 diffs)

trunk/src/wp-includes/option.php

@@ -2126 +2126 @@
     wp_protect_special_option( $option );
 
-    $old_value = get_network_option( $network_id, $option, false );
+    $old_value = get_network_option( $network_id, $option );
 
     /**
@@ -2146 +2146 @@
 
     /*
+     * To get the actual raw old value from the database, any existing pre filters need to be temporarily disabled.
+     * Immediately after getting the raw value, they are reinstated.
+     * The raw value is only used to determine whether a value is present in the database. It is not used anywhere
+     * else, and is not passed to any of the hooks either.
+     */
+    global $wp_filter;
+
+    /** This filter is documented in wp-includes/option.php */
+    $default_value = apply_filters( "default_site_option_{$option}", false, $option, $network_id );
+
+    $has_site_filter   = has_filter( "pre_site_option_{$option}" );
+    $has_option_filter = has_filter( "pre_option_{$option}" );
+    if ( $has_site_filter || $has_option_filter ) {
+        if ( $has_site_filter ) {
+            $old_ms_filters = $wp_filter[ "pre_site_option_{$option}" ];
+            unset( $wp_filter[ "pre_site_option_{$option}" ] );
+        }
+
+        if ( $has_option_filter ) {
+            $old_single_site_filters = $wp_filter[ "pre_option_{$option}" ];
+            unset( $wp_filter[ "pre_option_{$option}" ] );
+        }
+
+        if ( is_multisite() ) {
+            $raw_old_value = get_network_option( $network_id, $option );
+        } else {
+            $raw_old_value = get_option( $option, $default_value );
+        }
+
+        if ( $has_site_filter ) {
+            $wp_filter[ "pre_site_option_{$option}" ] = $old_ms_filters;
+        }
+        if ( $has_option_filter ) {
+            $wp_filter[ "pre_option_{$option}" ] = $old_single_site_filters;
+        }
+    } else {
+        $raw_old_value = $old_value;
+    }
+
+    if ( ! is_multisite() ) {
+        /** This filter is documented in wp-includes/option.php */
+        $default_value = apply_filters( "default_option_{$option}", $default_value, $option, true );
+    }
+
+    /*
      * If the new and old values are the same, no need to update.
      *
-     * Unserialized values will be adequate in most cases. If the unserialized
-     * data differs, the (maybe) serialized data is checked to avoid
-     * unnecessary database calls for otherwise identical object instances.
-     *
-     * See https://core.trac.wordpress.org/ticket/44956
-     */
-    if ( $value === $old_value || maybe_serialize( $value ) === maybe_serialize( $old_value ) ) {
+     * An exception applies when no value is set in the database, i.e. the old value is the default.
+     * In that case, the new value should always be added as it may be intentional to store it rather than relying on the default.
+     *
+     * See https://core.trac.wordpress.org/ticket/44956 and https://core.trac.wordpress.org/ticket/22192 and https://core.trac.wordpress.org/ticket/59360
+     */
+    if (
+        $value === $raw_old_value ||
+        (
+            false !== $raw_old_value &&
+            /*
+             * Single site stores values in the `option_value` field, which cannot be set to NULL.
+             * This means a PHP `null` value will be cast to an empty string, which can be considered
+             * equal to values such as an empty string, or false when cast to string.
+             *
+             * However, Multisite stores values in the `meta_value` field, which can be set to NULL.
+             * As NULL is unique in the database, skip checking an old or new value of NULL
+             * against any other value.
+             */
+            ( ! is_multisite() || ! ( null === $raw_old_value || null === $value ) ) &&
+            _is_equal_database_value( $raw_old_value, $value )
+        )
+    ) {
         return false;
     }
 
-    if ( false === $old_value ) {
+    if ( $default_value === $raw_old_value ) {
         return add_network_option( $network_id, $option, $value );
     }