code: public function init()
      {
          if ($this->version === null) {
              if (isset($_SERVER['SERVER_PROTOCOL']) && $_SERVER['SERVER_PROTOCOL'] === 'HTTP/1.0') {
                  $this->version = '1.0';
              } else {
                  $this->version = '1.1';
              }
          }
          if ($this->charset === null) {
              $this->charset = Yii::$app->charset;
          }
          $this->formatters = array_merge($this->defaultFormatters(), $this->formatters);
      }
docs: Initializes this component.