/**
* 生成token，key,password请找开发人员对接
*
*
*/

class Token {

private $parameters;
private $key = '';
private $password = '';

/**
* 生成签名
*
* @return string
*/
public function makeSign()
{
        // 设置校验时间戳
        !$this->getParameter('_timestamp') && $this->setParameter('_timestamp', date('YmdH'));
        // 设置密码
        !$this->getParameter('_password') && $this->setParameter('_password', $this->password);
        //签名步骤一：按字典序排序参数
        ksort($this->parameters);
        $string = $this->toUrlParams();
        //签名步骤二：在string后加入KEY
        $string = $string . '&' . $this->key;
        //签名步骤三：MD5加密
        $result = md5($string);
        //所有字符转为小写
        $sign = strtolower($result);

        return $sign;
}

/**
* 设置参数
* @param string $key
* @param string $value
*/
public function setParameter($key = '', $value = '')
{
if (!is_null($value) && !is_bool($value)) {
$this->parameters[$key] = $value;
}
}

/**
* 获取参数值
* @param $key
* @return string
*/
public function getParameter($key)
{
return isset($this->parameters[$key]) ? $this->parameters[$key] : '';
}

/**
* @return string
* @internal param array $params
*/
public function toUrlParams()
{
$buff = "";
foreach ($this->parameters as $k => $v) {
$buff .= $k . "=" . (is_array($v) ? json_encode($v) : $v) . "&";
}
$buff = trim($buff, "&");

return $buff;
}

}

生成access_token