controllers.controller('LoginController', ['$scope', '$http', '$window', '$location',
    function($scope, $http, $window, $location) {
        $scope.login = function () {
            $scope.submitted = true;
            $scope.error = {};
            $http.post('api/login', $scope.userModel).success(
                function (data) {
                    $window.sessionStorage.access_token = data.access_token;
                    $location.path('/dashboard').replace();
            }).error(
                function (data) {
                    angular.forEach(data, function (error) {
                        $scope.error[error.field] = error.message;
                    });
                }
            );
        };
    }
]);

public function actionLogin()
        {
            $model = new LoginForm();

            if ($model->load(Yii::$app->getRequest()->getBodyParams(), '') && $model->login()) {
                return ['access_token' => Yii::$app->user->identity->getAuthKey()];
            } else {
                $model->validate();
                return $model;
            }
        }

<form ng-submit="login()" name="loginForm" id="login-form" method="post" role="form" >
            <div ng-class="{ 'has-success': !error['username'] && submitted,
                'has-error': error['username'] && submitted }"
                 class="form-group field-loginform-username required">
                <label class="control-label" for="loginform-username">Username(demo)</label>
                <input ng-model="userModel.username" type="text" id="loginform-username" class="form-control">
                <p class="help-block help-block-error">{{ error['username'] }}</p>
            </div>

            <div ng-class="{ 'has-success': !error['password'] && submitted,
                'has-error': error['password'] && submitted }"
                 class="form-group field-loginform-password required">
                <label class="control-label" for="loginform-password">Password(demo)</label>
                <input ng-model="userModel.password" type="password" id="loginform-password" class="form-control">
                <p class="help-block help-block-error">{{ error['password'] }}</p>
            </div>

            <div class="form-group">
                <button type="submit" class="btn btn-primary" name="login-button">Login</button>
            </div>

        </form>