Get response in JSON format in Yii2

Question

I'm trying to convert and array of response into JSON format. I have tried all the answers that were posted on SO and other websites like web1,web2 adding header('Content-Type: application/json') and then echo json_encode($data,JSON_PRETTY_PRINT); But I'm always getting the output in text format. Can some one help me in solving this.

Helpers Class:

public static function renderJSON($data) {
    header('Content-Type: application/json');
    echo json_encode($data,JSON_PRETTY_PRINT);
}

My Controller:

if ($model->login()) {
    $user =  User::findByUsernameOrEmail($request->post('username'));
    $userArray = ArrayHelper::toArray($user);
    Helpers::renderJSON($userArray);

I tried to printing the userArray and it looks like this:

Array
(
    [name] => abc
    [lastname] => xyz
    [username] => test_test
)

Json output: (html/text)

{
    "name": "abc",
    "lastname": "xyz",
    "username": "test_test"
}

Answer 1

Set

\Yii::$app->response->format = \yii\web\Response::FORMAT_JSON;

in the controller's action somewhere before return.