php通过CURL模拟post提交请求

 <?php
     header("Content-type:text/html;charset=utf-8");

     class Test{

         public function request_post($url = '', $param = '',$headers = array()){
             if (empty($url) || empty($param) || empty($headers)) {
                 return false;
             }

             $postUrl    = $url;
             $curlPost   = $param;
             $curlHeader = $headers;
             $ch = curl_init();//初始化curl
             curl_setopt($ch, CURLOPT_URL,$postUrl);//抓取指定网页
             curl_setopt($ch, CURLOPT_HTTPHEADER, $curlHeader);//设置header
             curl_setopt($ch, CURLOPT_RETURNTRANSFER, );//要求结果为字符串且输出到屏幕上
             curl_setopt($ch, CURLOPT_POST, );//post提交方式
             curl_setopt($ch, CURLOPT_POSTFIELDS, $curlPost);
             $data = curl_exec($ch);//运行curl
             curl_close($ch);

             return $data;
         }

         public function testAction(){
             $url = 'http://web.zhimabot.com:8080/parsor9/robot';
             $post_data['app_id']        = '';
             $post_data['client_id']     = '';
             $post_data['session_id']    = '';
             $post_data['intent_update'] = '';
             $post_data['query']         = '播放刘德华的忘情水';

             $headers = array();
             array_push($headers, "Content-Type: application/json; charset=utf-8","Accept: application/json");
             $post_data = json_encode($post_data,JSON_UNESCAPED_UNICODE);

             $res = $this->request_post($url, $post_data,$headers);
             return $res;
         }

     }

     function fn(){
         $action = new Test();
         $result = $action->testAction();
         var_dump($result);
     }

     fn();

 ?>