Fixes issue #177.

apps/bootstrap/protected/config/main.php

@@ -3,6 +3,7 @@
 return array(
 	'id' => 'hello',
 	'basePath' => dirname(__DIR__),
+	'preload' => array('log'),
 	'components' => array(
 		'cache' => array(
 			'class' => 'yii\caching\FileCache',
@@ -14,6 +15,15 @@ return array(
 		'assetManager' => array(
 			'bundles' => require(__DIR__ . '/assets.php'),
 		),
+		'log' => array(
+			'class' => 'yii\logging\Router',
+			'targets' => array(
+				'file' => array(
+					'class' => 'yii\logging\FileTarget',
+					'levels' => array('error', 'warning'),
+				),
+			),
+		),
 	),
 	'params' => array(
 		'adminEmail' => 'admin@example.com',

framework/base/Application.php

@@ -8,7 +8,6 @@
 namespace yii\base;
 
 use Yii;
-use yii\helpers\FileHelper;
 
 /**
  * Application is the base class for all application classes.

framework/logging/Logger.php

@@ -6,7 +6,9 @@
  */
 
 namespace yii\logging;
-use yii\base\InvalidConfigException;
+
+use \yii\base\Component;
+use \yii\base\InvalidConfigException;
 
 /**
  * Logger records logged messages in memory.
@@ -17,7 +19,7 @@ use yii\base\InvalidConfigException;
  * @author Qiang Xue <qiang.xue@gmail.com>
  * @since 2.0
  */
-class Logger extends \yii\base\Component
+class Logger extends Component
 {
 	/**
 	 * Error message level. An error message is one that indicates the abnormal termination of the

framework/logging/Router.php

@@ -28,16 +28,16 @@ use yii\base\Application;
  *     'preload' => array('log'),
  *     'components' => array(
  *         'log' => array(
- *             'class' => '\yii\logging\Router',
+ *             'class' => 'yii\logging\Router',
  *             'targets' => array(
  *                 'file' => array(
- *                     'class' => '\yii\logging\FileTarget',
+ *                     'class' => 'yii\logging\FileTarget',
- *                     'levels' => 'trace, info',
+ *                     'levels' => array('trace', 'info'),
- *                     'categories' => 'yii\*',
+ *                     'categories' => array('yii\*'),
  *                 ),
  *                 'email' => array(
- *                     'class' => '\yii\logging\EmailTarget',
+ *                     'class' => 'yii\logging\EmailTarget',
- *                     'levels' => 'error, warning',
+ *                     'levels' => array('error', 'warning'),
  *                     'emails' => array('admin@example.com'),
  *                 ),
  *             ),
@@ -73,7 +73,6 @@ class Router extends Component
 	public function init()
 	{
 		parent::init();
-
 		foreach ($this->targets as $name => $target) {
 			if (!$target instanceof Target) {
 				$this->targets[$name] = Yii::createObject($target);