thinkphp 把小程序码二进制流存储到本地

 public function getxcxm(){
         $id = input('id');
         $astk = json_decode($this->getasstk())->access_token;
         $url = "https://api.weixin.qq.com/wxa/getwxacode?access_token=".$astk;
         $data = array(
             'path' => "pages/app/querytest?id=".$id,
             'width' => 430,
             'is_hyaline' => true
         );
         $xcxm = $this->http_request($url,json_encode($data));
         $path = ROOT_PATH . 'public/upload/'.date("Ymd/");
         if(!is_dir($path)){
             mkdir($path,0755,true);
         }
         $filepath = $path.time().".png";
         $file = fopen($filepath,"w");
         fwrite($file,$xcxm);
         fclose($file);
         return $filepath;
     }

实际开发中 我这样写的：

 //获取小程序码
     public function getxcxm(){
         $id = input('id');
         //先从本地读取，本地没有再向微信提取
         $ckname = ROOT_PATH . 'public/upload/recode/'.$id.".png";
         if(file_exists($ckname)){
             return str_replace("/www/wwwroot/","https://",$ckname);
         }else{
             $astk = json_decode($this->getasstk())->access_token;
             $url = "https://api.weixin.qq.com/wxa/getwxacode?access_token=".$astk;
             $data = array(
                 'path' => "pages/app/querytest?id=".$id,
                 'width' => 430,
                 'is_hyaline' => true
             );
             $xcxm = $this->http_request($url,json_encode($data));
             $path = ROOT_PATH . 'public/upload/recode/';
             if(!is_dir($path)){
                 mkdir($path,0755,true);
             }
             $filepath = $path.$id.".png";
             $file = fopen($filepath,"w");
             fwrite($file,$xcxm);
             fclose($file);
             return str_replace("/www/wwwroot/","https://",$filepath);
         }
     }