Yii2高级版本复制新项目出现报错 [ 2.0 版本 ]

做法如下：
1、cp -r backend api
2、把api里的backend关键字替换成api

加了别名配置也一样错误 Yii::setAlias('api', dirname(dirname(DIR)) . '/api’);

报错如下

exception 'yii\base\InvalidRouteException' with message 'Unable to resolve the request "site/error".' in /Users/trylife/demo/vendor/yiisoft/yii2/base/Module.php:461
Stack trace:
#0 /Users/trylife/demo/vendor/yiisoft/yii2/web/ErrorHandler.php(80): yii\base\Module->runAction('site/error')
#1 /Users/trylife/demo/vendor/yiisoft/yii2/base/ErrorHandler.php(95): yii\web\ErrorHandler->renderException(Object(yii\web\NotFoundHttpException))
#2 [internal function]: yii\base\ErrorHandler->handleException(Object(yii\web\NotFoundHttpException))
#3 {main}
Previous exception:
exception 'yii\base\InvalidRouteException' with message 'Unable to resolve the request "".' in /Users/trylife/demo/vendor/yiisoft/yii2/base/Module.php:461
Stack trace:
#0 /Users/trylife/demo/vendor/yiisoft/yii2/web/Application.php(83): yii\base\Module->runAction('', Array)
#1 /Users/trylife/demo/vendor/yiisoft/yii2/base/Application.php(375): yii\web\Application->handleRequest(Object(yii\web\Request))
#2 /Users/trylife/demo/api/web/index.php(18): yii\base\Application->run()
#3 {main}

Next exception 'yii\web\NotFoundHttpException' with message 'Page not found.' in /Users/trylife/demo/vendor/yiisoft/yii2/web/Application.php:95
Stack trace:
#0 /Users/trylife/demo/vendor/yiisoft/yii2/base/Application.php(375): yii\web\Application->handleRequest(Object(yii\web\Request))
#1 /Users/trylife/demo/api/web/index.php(18): yii\base\Application->run()
#2 {main}