allow basic auth for users not logged in

basicauth.php

<?php

class SomeController extends yii\web\Controller
{
    /**
	 * @var array actions to authenticate via basicAuth if not logged in.
	 */
	public $basicAuthActions = [];
    
    /**
	 * Allow login via HTTP basic auth if iCal calendar url is used in Thunderbird or similar applications
	 */
	public function beforeAction($action)
	{
		// this has to come before calling the parent implementation
		// so that we have a user instance to run access checks against
		if (Yii::$app->user->isGuest && in_array($action->id, $this->basicAuthActions)) {
			Yii::$app->user->enableSession = false;
			$auth = new HttpBasicAuth();
			$auth->auth = function($username, $password) {
				$user = User::findIdentityByName($username);
				if (!$user || !$user->validatePassword($password)) {
					return null;
				}
				return $user;
			};
			$auth->beforeAction($action);
		}
		return parent::beforeAction($action);
	}
  
  // ...
}