src/Auth/SingleUserAuth.php
protected function getRequestString()
    {
        $params = array_merge($this->getParams, $this->postParams, $this->getOauthParameters());

        $params = $this->curl->getParams($params);

        return rawurlencode($params);
    }
protected function getRequestString()
    {
        $params = array_merge($this->getParams, $this->postParams, $this->getOauthParameters());

        $params = $this->curl->getParams($params);

        return rawurlencode($params);
    }
Converting all parameters agetrrays to a single string with encoded values

@return string  Single string with encoded values