Ticket #30261: 30261.16.diff

src/wp-admin/includes/upgrade.php

@@ -1505 +1505 @@
                 upgrade_430_fix_comments();
         }
 
+        // Shared terms are split in a separate process.
         if ( $wp_current_db_version < 32814 ) {
-                split_all_shared_terms();
+                wp_schedule_single_event( time() + ( 1 * MINUTE_IN_SECONDS ), 'wp_split_shared_term_batch' );
         }
 
         if ( $wp_current_db_version < 33055 && 'utf8mb4' === $wpdb->charset ) {
@@ -1881 +1882 @@
 }
 
 /**
- * Splits all shared taxonomy terms.
- *
- * @since 4.3.0
- *
- * @global wpdb $wpdb WordPress database abstraction object.
- */
-function split_all_shared_terms() {
-        global $wpdb;
-
-        // Get a list of shared terms (those with more than one associated row in term_taxonomy).
-        $shared_terms = $wpdb->get_results(
-                "SELECT tt.term_id, t.*, count(*) as term_tt_count FROM {$wpdb->term_taxonomy} tt
-                 LEFT JOIN {$wpdb->terms} t ON t.term_id = tt.term_id
-                 GROUP BY t.term_id
-                 HAVING term_tt_count > 1"
-        );
-
-        if ( empty( $shared_terms ) ) {
-                return;
-        }
-
-        // Rekey shared term array for faster lookups.
-        $_shared_terms = array();
-        foreach ( $shared_terms as $shared_term ) {
-                $term_id = intval( $shared_term->term_id );
-                $_shared_terms[ $term_id ] = $shared_term;
-        }
-        $shared_terms = $_shared_terms;
-
-        // Get term taxonomy data for all shared terms.
-        $shared_term_ids = implode( ',', array_keys( $shared_terms ) );
-        $shared_tts = $wpdb->get_results( "SELECT * FROM {$wpdb->term_taxonomy} WHERE `term_id` IN ({$shared_term_ids})" );
-
-        // Split term data recording is slow, so we do it just once, outside the loop.
-        $suspend = wp_suspend_cache_invalidation( true );
-        $split_term_data = get_option( '_split_terms', array() );
-        $skipped_first_term = $taxonomies = array();
-        foreach ( $shared_tts as $shared_tt ) {
-                $term_id = intval( $shared_tt->term_id );
-
-                // Don't split the first tt belonging to a given term_id.
-                if ( ! isset( $skipped_first_term[ $term_id ] ) ) {
-                        $skipped_first_term[ $term_id ] = 1;
-                        continue;
-                }
-
-                if ( ! isset( $split_term_data[ $term_id ] ) ) {
-                        $split_term_data[ $term_id ] = array();
-                }
-
-                // Keep track of taxonomies whose hierarchies need flushing.
-                if ( ! isset( $taxonomies[ $shared_tt->taxonomy ] ) ) {
-                        $taxonomies[ $shared_tt->taxonomy ] = 1;
-                }
-
-                // Split the term.
-                $split_term_data[ $term_id ][ $shared_tt->taxonomy ] = _split_shared_term( $shared_terms[ $term_id ], $shared_tt, false );
-        }
-
-        // Rebuild the cached hierarchy for each affected taxonomy.
-        foreach ( array_keys( $taxonomies ) as $tax ) {
-                delete_option( "{$tax}_children" );
-                _get_term_hierarchy( $tax );
-        }
-
-        wp_suspend_cache_invalidation( $suspend );
-        update_option( '_split_terms', $split_term_data );
-}
-
-/**
  * Retrieve all options as it was for 1.2.
  *
  * @since 1.2.0

src/wp-includes/default-filters.php

@@ -328 +328 @@
 add_filter( 'determine_current_user', 'wp_validate_logged_in_cookie', 20 );
 
 // Split term updates.
+add_action( 'admin_init',        '_wp_check_for_scheduled_split_terms' );
 add_action( 'split_shared_term', '_wp_check_split_default_terms',  10, 4 );
 add_action( 'split_shared_term', '_wp_check_split_terms_in_menus', 10, 4 );
 add_action( 'split_shared_term', '_wp_check_split_nav_menu_terms', 10, 4 );
+add_action( 'wp_split_shared_term_batch', '_wp_batch_split_terms' );
 
 /**
  * Filters formerly mixed into wp-includes

src/wp-includes/taxonomy.php

@@ -4249 +4249 @@
                 $term_taxonomy_id = intval( $term_taxonomy->term_taxonomy_id );
         }
 
-        // Don't try to split terms if database schema does not support shared slugs.
-        $current_db_version = get_option( 'db_version' );
-        if ( $current_db_version < 30133 ) {
-                return $term_id;
-        }
-
         // If there are no shared term_taxonomy rows, there's nothing to do here.
         $shared_tt_count = $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM $wpdb->term_taxonomy tt WHERE tt.term_id = %d AND tt.term_taxonomy_id != %d", $term_id, $term_taxonomy_id ) );
 
@@ -4262 +4256 @@
                 return $term_id;
         }
 
+        /*
+         * Verify that the term_taxonomy_id passed to the function is actually associated with the term_id.
+         * If there's a mismatch, it may mean that the term is already split. Return the actual term_id from the db.
+         */
+        $check_term_id = $wpdb->get_var( $wpdb->prepare( "SELECT term_id FROM $wpdb->term_taxonomy WHERE term_taxonomy_id = %d", $term_taxonomy_id ) );
+        if ( $check_term_id != $term_id ) {
+                return $check_term_id;
+        }
+
         // Pull up data about the currently shared slug, which we'll use to populate the new one.
         if ( empty( $shared_term ) ) {
                 $shared_term = $wpdb->get_row( $wpdb->prepare( "SELECT t.* FROM $wpdb->terms t WHERE t.term_id = %d", $term_id ) );
@@ -4339 +4342 @@
 }
 
 /**
+ * Splits a batch of shared taxonomy terms.
+ *
+ * @since 4.3.0
+ *
+ * @global wpdb $wpdb WordPress database abstraction object.
+ */
+function _wp_batch_split_terms() {
+        global $wpdb;
+
+        $lock_name = 'term_split.lock';
+
+        // Try to lock.
+        $lock_result = $wpdb->query( $wpdb->prepare( "INSERT IGNORE INTO `$wpdb->options` ( `option_name`, `option_value`, `autoload` ) VALUES (%s, %s, 'no') /* LOCK */", $lock_name, time() ) );
+
+        if ( ! $lock_result ) {
+                $lock_result = get_option( $lock_name );
+
+                // Bail if we were unable to create a lock, or if the existing lock is still valid.
+                if ( ! $lock_result || ( $lock_result > ( time() - HOUR_IN_SECONDS ) ) ) {
+                        wp_schedule_single_event( time() + ( 5 * MINUTE_IN_SECONDS ), 'wp_split_shared_term_batch' );
+                        return;
+                }
+        }
+
+        // Update the lock, as by this point we've definitely got a lock, just need to fire the actions.
+        update_option( $lock_name, time() );
+
+        // Get a list of shared terms (those with more than one associated row in term_taxonomy).
+        $shared_terms = $wpdb->get_results(
+                "SELECT tt.term_id, t.*, count(*) as term_tt_count FROM {$wpdb->term_taxonomy} tt
+                 LEFT JOIN {$wpdb->terms} t ON t.term_id = tt.term_id
+                 GROUP BY t.term_id
+                 HAVING term_tt_count > 1
+                 LIMIT 20"
+        );
+
+        // No more terms, we're done here.
+        if ( ! $shared_terms ) {
+                update_option( 'finished_splitting_shared_terms', true );
+                delete_option( $lock_name );
+                return;
+        }
+
+        // Shared terms found? We'll need to run this script again.
+        wp_schedule_single_event( time() + ( 2 * MINUTE_IN_SECONDS ), 'wp_split_shared_term_batch' );
+
+        // Rekey shared term array for faster lookups.
+        $_shared_terms = array();
+        foreach ( $shared_terms as $shared_term ) {
+                $term_id = intval( $shared_term->term_id );
+                $_shared_terms[ $term_id ] = $shared_term;
+        }
+        $shared_terms = $_shared_terms;
+
+        // Get term taxonomy data for all shared terms.
+        $shared_term_ids = implode( ',', array_keys( $shared_terms ) );
+        $shared_tts = $wpdb->get_results( "SELECT * FROM {$wpdb->term_taxonomy} WHERE `term_id` IN ({$shared_term_ids})" );
+
+        // Split term data recording is slow, so we do it just once, outside the loop.
+        $suspend = wp_suspend_cache_invalidation( true );
+        $split_term_data = get_option( '_split_terms', array() );
+        $skipped_first_term = $taxonomies = array();
+        foreach ( $shared_tts as $shared_tt ) {
+                $term_id = intval( $shared_tt->term_id );
+
+                // Don't split the first tt belonging to a given term_id.
+                if ( ! isset( $skipped_first_term[ $term_id ] ) ) {
+                        $skipped_first_term[ $term_id ] = 1;
+                        continue;
+                }
+
+                if ( ! isset( $split_term_data[ $term_id ] ) ) {
+                        $split_term_data[ $term_id ] = array();
+                }
+
+                // Keep track of taxonomies whose hierarchies need flushing.
+                if ( ! isset( $taxonomies[ $shared_tt->taxonomy ] ) ) {
+                        $taxonomies[ $shared_tt->taxonomy ] = 1;
+                }
+
+                // Split the term.
+                $split_term_data[ $term_id ][ $shared_tt->taxonomy ] = _split_shared_term( $shared_terms[ $term_id ], $shared_tt, false );
+        }
+
+        // Rebuild the cached hierarchy for each affected taxonomy.
+        foreach ( array_keys( $taxonomies ) as $tax ) {
+                delete_option( "{$tax}_children" );
+                _get_term_hierarchy( $tax );
+        }
+
+        wp_suspend_cache_invalidation( $suspend );
+        update_option( '_split_terms', $split_term_data );
+
+        delete_option( $lock_name );
+}
+
+/**
+ * In order to avoid the wp_batch_split_terms() job being accidentally removed,
+ * check that it's still scheduled while we haven't finished splitting terms.
+ *
+ * @ignore
+ * @since 4.3.0
+ */
+function _wp_check_for_scheduled_split_terms() {
+        if ( ! get_option( 'finished_splitting_shared_terms' ) && ! wp_next_scheduled( 'wp_batch_split_terms' ) ) {
+                wp_schedule_single_event( 'wp_batch_split_terms', time() + MINUTE_IN_SECONDS );
+        }
+}
+
+/**
  * Check default categories when a term gets split to see if any of them need to be updated.
  *
  * @ignore