| 
<?php/**
 * Multisite upgrade administration panel.
 *
 * @package WordPress
 * @subpackage Multisite
 * @since 3.0.0
 */
 
 /** Load WordPress Administration Bootstrap */
 require_once __DIR__ . '/admin.php';
 
 require_once ABSPATH . WPINC . '/http.php';
 
 // Used in the HTML title tag.
 $title       = __( 'Upgrade Network' );
 $parent_file = 'upgrade.php';
 
 get_current_screen()->add_help_tab(
 array(
 'id'      => 'overview',
 'title'   => __( 'Overview' ),
 'content' =>
 '<p>' . __( 'Only use this screen once you have updated to a new version of WordPress through Updates/Available Updates (via the Network Administration navigation menu or the Toolbar). Clicking the Upgrade Network button will step through each site in the network, five at a time, and make sure any database updates are applied.' ) . '</p>' .
 '<p>' . __( 'If a version update to core has not happened, clicking this button will not affect anything.' ) . '</p>' .
 '<p>' . __( 'If this process fails for any reason, users logging in to their sites will force the same update.' ) . '</p>',
 )
 );
 
 get_current_screen()->set_help_sidebar(
 '<p><strong>' . __( 'For more information:' ) . '</strong></p>' .
 '<p>' . __( '<a href="https://developer.wordpress.org/advanced-administration/multisite/admin/#network-admin-updates-screen">Documentation on Upgrade Network</a>' ) . '</p>' .
 '<p>' . __( '<a href="https://wordpress.org/support/forums/">Support forums</a>' ) . '</p>'
 );
 
 require_once ABSPATH . 'wp-admin/admin-header.php';
 
 if ( ! current_user_can( 'upgrade_network' ) ) {
 wp_die( __( 'Sorry, you are not allowed to access this page.' ), 403 );
 }
 
 echo '<div class="wrap">';
 echo '<h1>' . __( 'Upgrade Network' ) . '</h1>';
 
 $action = isset( $_GET['action'] ) ? $_GET['action'] : 'show';
 
 switch ( $action ) {
 case 'upgrade':
 $n = ( isset( $_GET['n'] ) ) ? (int) $_GET['n'] : 0;
 
 if ( $n < 5 ) {
 /**
 * @global int $wp_db_version WordPress database version.
 */
 global $wp_db_version;
 update_site_option( 'wpmu_upgrade_site', $wp_db_version );
 }
 
 $site_ids = get_sites(
 array(
 'spam'                   => 0,
 'deleted'                => 0,
 'archived'               => 0,
 'network_id'             => get_current_network_id(),
 'number'                 => 5,
 'offset'                 => $n,
 'fields'                 => 'ids',
 'order'                  => 'DESC',
 'orderby'                => 'id',
 'update_site_meta_cache' => false,
 )
 );
 if ( empty( $site_ids ) ) {
 echo '<p>' . __( 'All done!' ) . '</p>';
 break;
 }
 echo '<ul>';
 foreach ( (array) $site_ids as $site_id ) {
 switch_to_blog( $site_id );
 $siteurl     = site_url();
 $upgrade_url = admin_url( 'upgrade.php?step=upgrade_db' );
 restore_current_blog();
 
 echo "<li>$siteurl</li>";
 
 $response = wp_remote_get(
 $upgrade_url,
 array(
 'timeout'     => 120,
 'httpversion' => '1.1',
 'sslverify'   => false,
 )
 );
 
 if ( is_wp_error( $response ) ) {
 wp_die(
 sprintf(
 /* translators: 1: Site URL, 2: Server error message. */
 __( 'Warning! Problem updating %1$s. Your server may not be able to connect to sites running on it. Error message: %2$s' ),
 $siteurl,
 '<em>' . $response->get_error_message() . '</em>'
 )
 );
 }
 
 /**
 * Fires after the Multisite DB upgrade for each site is complete.
 *
 * @since MU (3.0.0)
 *
 * @param array $response The upgrade response array.
 */
 do_action( 'after_mu_upgrade', $response );
 
 /**
 * Fires after each site has been upgraded.
 *
 * @since MU (3.0.0)
 *
 * @param int $site_id The Site ID.
 */
 do_action( 'wpmu_upgrade_site', $site_id );
 }
 echo '</ul>';
 ?><p><?php _e( 'If your browser does not start loading the next page automatically, click this link:' ); ?> <a class="button" href="upgrade.php?action=upgrade&n=<?php echo ( $n + 5 ); ?>"><?php _e( 'Next Sites' ); ?></a></p>
 <script type="text/javascript">
 <!--
 function nextpage() {
 location.href = "upgrade.php?action=upgrade&n=<?php echo ( $n + 5 ); ?>";
 }
 setTimeout( "nextpage()", 250 );
 //-->
 </script>
 <?php
 break;
 case 'show':
 default:
 if ( (int) get_site_option( 'wpmu_upgrade_site' ) !== $GLOBALS['wp_db_version'] ) :
 ?>
 <h2><?php _e( 'Database Update Required' ); ?></h2>
 <p><?php _e( 'WordPress has been updated! Next and final step is to individually upgrade the sites in your network.' ); ?></p>
 <?php endif; ?>
 
 <p><?php _e( 'The database update process may take a little while, so please be patient.' ); ?></p>
 <p><a class="button button-primary" href="upgrade.php?action=upgrade"><?php _e( 'Upgrade Network' ); ?></a></p>
 <?php
 /**
 * Fires before the footer on the network upgrade screen.
 *
 * @since MU (3.0.0)
 */
 do_action( 'wpmu_upgrade_page' );
 break;
 }
 ?>
 </div>
 
 <?php require_once ABSPATH . 'wp-admin/admin-footer.php'; ?>
 
 |