Ticket #45749: 45749.2.diff

src/wp-includes/class-wp-site-query.php

@@ -288 +288 @@
                         $this->meta_query_clauses = $this->meta_query->get_sql( 'blog', $wpdb->blogs, 'blog_id', $this );
                 }
 
-                // $args can include anything. Only use the args defined in the query_var_defaults to compute the key.
-                $_args = wp_array_slice_assoc( $this->query_vars, array_keys( $this->query_var_defaults ) );
 
-                // Ignore the $fields argument as the queried result will be the same regardless.
-                unset( $_args['fields'] );
+                /**
+                 * Filter the sites array before the query takes place.
+                 *
+                 * Return a non-null value to bypass WordPress's default site queries.
+                 *
+                 *
+                 * @since 5.2.0
+                 *
+                 * @param array|null $site_ids Return an array of site data to short-circuit WP's site query,
+                 *                             or null to allow WP to run its normal queries.
+                 * @param WP_Query   $this     The WP_Site_Query instance, passed by reference.
+                 */
+                $site_ids = apply_filters_ref_array( 'sites_pre_query', array( null, &$this ) );
 
-                $key          = md5( serialize( $_args ) );
-                $last_changed = wp_cache_get_last_changed( 'sites' );
+                if ( null === $site_ids ) {
 
-                $cache_key   = "get_sites:$key:$last_changed";
-                $cache_value = wp_cache_get( $cache_key, 'sites' );
+                        // $args can include anything. Only use the args defined in the query_var_defaults to compute the key.
+                        $_args = wp_array_slice_assoc( $this->query_vars, array_keys( $this->query_var_defaults ) );
 
-                if ( false === $cache_value ) {
-                        $site_ids = $this->get_site_ids();
-                        if ( $site_ids ) {
-                                $this->set_found_sites();
-                        }
+                        // Ignore the $fields argument as the queried result will be the same regardless.
+                        unset( $_args['fields'] );
 
-                        $cache_value = array(
-                                'site_ids'    => $site_ids,
-                                'found_sites' => $this->found_sites,
-                        );
-                        wp_cache_add( $cache_key, $cache_value, 'sites' );
-                } else {
-                        $site_ids          = $cache_value['site_ids'];
-                        $this->found_sites = $cache_value['found_sites'];
+                        $key          = md5( serialize( $_args ) );
+                        $last_changed = wp_cache_get_last_changed( 'sites' );
+
+                        $cache_key   = "get_sites:$key:$last_changed";
+                        $cache_value = wp_cache_get( $cache_key, 'sites' );
+
+                        if ( false === $cache_value ) {
+                                $site_ids = $this->get_site_ids();
+                                if ( $site_ids ) {
+                                        $this->set_found_sites();
+                                }
+
+                                $cache_value = array(
+                                        'site_ids'    => $site_ids,
+                                        'found_sites' => $this->found_sites,
+                                );
+                                wp_cache_add( $cache_key, $cache_value, 'sites' );
+                        } else {
+                                $site_ids          = $cache_value['site_ids'];
+                                $this->found_sites = $cache_value['found_sites'];
+                        }
                 }
 
                 if ( $this->found_sites && $this->query_vars['number'] ) {