public function getData($key = null)
    {
        if ($key === null) {
            return $this->extraData;
        } elseif (isset($this->extraData[$key])) {
            return $this->extraData[$key];
        } else {
            return null;
        }
    }
public function getData($key = null)
    {
        if ($key === null) {
            return $this->extraData;
        } elseif (isset($this->extraData[$key])) {
            return $this->extraData[$key];
        } else {
            return null;
        }
    }
public function getData ( $ key = null ) { if ( $ key === null ) { return $ this -> extraData ; } elseif ( isset ( $ this -> extraData [ $ key ] ) ) { return $ this -> extraData [ $ key ] ; } else { return null ; } }
Get arbitrary data from the service description that is not part of the
Guzzle service description specification.

@param string $key Data key to retrieve or null to retrieve all extra

@return null|mixed
Get arbitrary data from the service description that is not part of the Guzzle service description specification .