Fixes #5619: `yii\log\Target` should not attempt to start session when there is none

framework/CHANGELOG.md

@@ -10,6 +10,7 @@ Yii Framework 2 Change Log
 - Bug #5570: `yii\bootstrap\Tabs` would throw an exception if `content` is not set for one of its `items` (RomeroMsk)
 - Bug #5584: `yii\rbac\DbRbacManager` should not delete items when deleting a rule on a database not supporting cascade update (mdmunir)
 - Bug #5601: Simple conditions in Query::where() and ActiveQuery::where() did not allow `yii\db\Expression` to be used as the value (cebe, stevekr)
+- Bug #5619: `yii\log\Target` should not attempt to start session when there is none (klimov-paul, qiangxue)  
 - Bug #5657: `yii\caching\ApcCache::mset()` and `madd()` may cause warning in some APC setup (LAV45)
 - Bug #5665: The `currentPage` meta data in the RESTful result should be 1-based, similar to that in HTTP headers (qiangxue)
 - Bug #5682: The `asset` command would incorrectly combine CSS files when `UrlManager::linkAssets` is true (dmvslv)

framework/log/Target.php

@@ -270,8 +270,13 @@ abstract class Target extends Component
         $ip = $request instanceof Request ? $request->getUserIP() : '-';
 
         /* @var $user \yii\web\User */
+
         $user = Yii::$app->has('user', true) ? Yii::$app->get('user') : null;
-        $userID = $user ? $user->getId(false) : '-';
+        if ($user && ($identity = $user->getIdentity(false))) {
+            $userID = $identity->getId();
+        } else {
+            $userID = '-';
+        }
 
         /* @var $session \yii\web\Session */
         $session = Yii::$app->has('session', true) ? Yii::$app->get('session') : null;