Why is className() method in yii2-basic not working properly?

Question

Yii

Installed the app yii2-basicfrom scratch. In the config I web.phpchange the line:
It was:

'user' => [
  'identityClass'   => 'app\models\User',
  'enableAutoLogin' => true,
],

It became:

'user' => [
  'identityClass'   => app\models\User::className(),
  'enableAutoLogin' => true,
],

As a result, error 500. In the logs

PHP Fatal error:  Class 'app\\models\\User' not found in ...

And in yii2-advanced this works without dancing.

Answer 1

in Yii advanced, basic aliases are pre-installed, i.e. approximately the scheme is as follows:
1. Install aliases
2. Load the configuration
3. Launch the application with the loaded configuration
Accordingly, at the time of loading the configuration, php already knows which alias which path belongs to. In basic, there are no pre-installation of aliases, i.e. the configuration is loaded, then the application is launched, during the launch of which aliases are installed. Therefore, at the time of loading the config, php simply does not yet know what app is. Those. You are accessing the class app\models\User::className() but php doesn't know what app is at this point, because this alias is not yet defined.
You can define aliases yourself before the application is loaded using the Yii::setAlias ​​method

Answer 2

Hello.
-
Another surprise awaits you. The fact is that the developers of the Yii2 Framework solved the issue with the loads on the site, and they had to abandon the ::className(), since php7 already has a solution for referring to classes, the whole structure will be replaced by ::class().
So, even if you resolve the alias issues, your classes may stop working again. Personally, I find this appeal to classes convenient, the code is noticeably reduced, and according to the debugger, everything is much better ))