public function getAccessToken($code)
{
$params = ['client_id' => $this->appKey, 'client_secret' => $this->appSecret, 'grant_type' => $this->grantType, 'redirect_uri' => $this->callback, 'code' => $code];
// 获取token信息
$data = $this->http($this->getAccessTokenURL, $params, 'POST');
// 解析token
$this->token = $this->parseToken($data);
return $this->token;
}