/**
  * Class constructor
  */
 public function __construct()
 {
     # define the base URL for the class
     $this->baseUrl = getenv('CMAPIPATH');
     # helpers.php function
     $this->clientId = $this->setClientId(getClientIdentifier());
 }
 /**
  * Request an individual user be subscribed to the email list
  * @return mixed
  */
 public function subscribe(\App\V1\Lib\MailLogger $logger)
 {
     if (!isset($_POST['listId']) or !isset($_POST['userEmail']) or !isset($_POST['fields']) or !isset($_POST['userName'])) {
         return apiErrorResponse('badRequest');
     }
     $listId = $_POST['listId'];
     # make sure supplied list ID is a valid list
     if (!$this->mailer->getList($listId)) {
         return apiErrorResponse('unprocessable', ['errors' => 'Unknown list ID']);
     }
     $userEmail = $_POST['userEmail'];
     $userName = $_POST['userName'];
     $fields = $_POST['fields'];
     # log the subscription request which we'll try and action later on
     return $logger->log($userEmail, $userName, $fields, $listId, getClientIdentifier());
 }