Session: Don't subscribe all users from usergroups when importing session and classes doesn't exist - refs BT#20250

main/inc/lib/sessionmanager.lib.php

@@ -5924,7 +5924,7 @@ class SessionManager
                         WHERE id = '$session_id'";
                 Database::query($sql);
 
-                self::addClassesByName($session_id, $classes, false);
+                self::addClassesByName($session_id, $classes, false, $error_message);
 
                 if ($debug) {
                     $logger->addInfo("End process session #$session_id -------------------- ");
@@ -10001,7 +10001,7 @@ class SessionManager
      * @param array $classesNames
      * @param bool  $deleteClassSessions Optional. Empty the session list for the usergroup (class)
      */
-    private static function addClassesByName($sessionId, $classesNames, $deleteClassSessions = true)
+    private static function addClassesByName($sessionId, $classesNames, $deleteClassSessions = true, ?string &$error_message = '')
     {
         if (!$classesNames) {
             return;
@@ -10014,6 +10014,13 @@ class SessionManager
                 continue;
             }
 
+            $classIdByName = $usergroup->getIdByName($className);
+
+            if (empty($classIdByName)) {
+                $error_message .= sprintf(get_lang('ClassNameXDoesntExists'), $className).'<br>';
+                continue;
+            }
+
             $usergroup->subscribe_sessions_to_usergroup(
                 $usergroup->getIdByName($className),
                 [$sessionId],

main/session/session_import.php

@@ -459,7 +459,7 @@ if (isset($_POST['formSent']) && $_POST['formSent']) {
             header('Location: resume_session.php?id_session='.$session_id);
             exit;
         } else {
-            Display::addFlash(Display::return_message(get_lang('FileImported').' '.$error_message));
+            Display::addFlash(Display::return_message(get_lang('FileImported').' '.$error_message, 'normal', false));
             header('Location: session_list.php');
             exit;
         }