Ticket #6481: wp-admin_includes_upgrade.php.diff

wp-admin/includes/upgrade.php

@@ -117 +117 @@
  * @param int $user_id User ID.
  */
 function wp_install_defaults( $user_id ) {
-        global $wpdb, $wp_rewrite, $table_prefix;
+        global $wpdb, $table_prefix;
 
         // Default category
         $cat_name = __('Uncategorized');
@@ -240 +240 @@
                 update_user_meta( $user_id, 'show_welcome_panel', 1 );
         elseif ( ! is_super_admin( $user_id ) && ! metadata_exists( 'user', $user_id, 'show_welcome_panel' ) )
                 update_user_meta( $user_id, 'show_welcome_panel', 2 );
+        
+        // perform a proper test on installation of whether the pretty permalinks can be used on this server
+        // https://core.trac.wordpress.org/ticket/6481
+        wp_install_default_permalinks();
 
         if ( is_multisite() ) {
-                // Flush rules to pick up the new page.
-                $wp_rewrite->init();
-                $wp_rewrite->flush_rules();
-
                 $user = new WP_User($user_id);
                 $wpdb->update( $wpdb->options, array('option_value' => $user->user_email), array('option_name' => 'admin_email') );
 
@@ -260 +260 @@
 }
 endif;
 
+if ( !function_exists('wp_install_default_permalinks') ) :
+/**
+ * Tests whether pretty permalinks can be used on this installation.
+ *
+ * Performs a test to see if pretty permalinks can be used on this server by default. If the server
+ * is configurable to allow this, the use the basic /%postname%/ permalink style as the default
+ * instead of the ugly ?p=123 permalink style.
+ *
+ * @since 4.1.0
+ */
+function wp_install_default_permalinks() {
+        global $wp_rewrite;
+
+        if ( ! $wp_rewrite->using_permalinks() && ! $wp_rewrite->using_index_permalinks() ) {
+                // if we are not already using pretty permalinks (probably from a repair of an old install)
+
+                $wp_rewrite->init();
+
+                // attempt to use pretty permalinks
+                $wp_rewrite->set_permalink_structure( '/%postname%/' );
+
+                // force writing of the relevant config file
+                $wp_rewrite->flush_rules( true );
+
+                // test to make sure that the pretty permalink strucutre is working. test the permalink of the post
+                // we just created in the wp_install_defaults() function, with post_id 1
+                $response = wp_remote_request( get_permalink( 1 ), array(
+                        'method'    => 'HEAD',
+                        'blocking'  => true,
+                        'timeout'   => 0.1,
+                        'sslverify' => apply_filters( 'https_local_ssl_verify', false )
+                ) );
+
+                $worked = false;
+
+                // parse the response
+                if ( is_array( $response ) && isset( $response['response'], $response['response']['code'] ) && $response['response']['code'] == 200 )
+                        $worked = true;
+
+                // if this test failed, then fallback to no permalink_structure, AKA ugly permalinks
+                if ( ! $worked ) {
+                        $wp_rewrite->init();
+                        $wp_rewrite->set_permalink_structure( '' );
+                        $wp_rewrite->flush_rules();
+                }
+        } else if ( is_multisite() ) {
+                // oterhwise still recalculate the rewrite rules as before when multisite, so that the sites
+                // get the new page that was created by the wp_install_defaults() function
+                $wp_rewrite->init();
+                $wp_rewrite->flush_rules();
+        }
+}
+endif;
+
 if ( !function_exists('wp_new_blog_notification') ) :
 /**
  * {@internal Missing Short Description}}