今天做一个访问阿里云api刷新缓存的功能，开始想找sdk的，但是没找到，只有一个个方法找，其实改好了发现也不是难的。
### 请求参数

function setParameter($specialParameter){
    $time            = date('Y-m-d H:i:s', time()-8*60*60);//北京时间转换为UTC时间
    $var             = strtr($time, ' ', 'T');
    $Timestamp       = $var . 'Z';
    $signature_nonce = '';
   for($i =0 ; $i < 14; $i++){
        $signature_nonce .= mt_rand(0,9);
       }

   $publicParameter = array(
        'Format'           => 'JSON',
        'Version'          => '2014-11-11',
        'SignatureMethod'  => 'HMAC-SHA1',
        'TimeStamp'        => $Timestamp,
        'SignatureVersion' => '1.0',
        'SignatureNonce'   => $signature_nonce,
        'ObjectType'       => 'File'
   );

   $parameter = array_merge($publicParameter, $specialParameter);
   return $parameter;
}

将参数排序并添加$signature

function getStringToSign($parameter,$access_key_secret){
       ksort($parameter);
       foreach($parameter as $key => $value){
          $str[] = rawurlencode($key). "=" .rawurlencode($value);
       }
       $ss = "";
       if(!empty($str)){
          for($i=0; $i<count($str); $i++){
             if(!isset($str[$i+1])){
                $ss .= $str[$i];
             }else{
                $ss .= $str[$i]."&";
            }
          }
       }
    $StringToSign = "GET" . "&" . rawurlencode("/") . "&" . rawurlencode($ss);
    $signature    = base64_encode(hash_hmac("sha1", $StringToSign, $access_key_secret."&", true));
    $url          = "https://cdn.aliyuncs.com/?" . $ss . "&Signature=" . $signature;
       return $url;
}

curl访问

function curl_get($url){
   $ch = curl_init();
   curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);    // https请求 不验证证书和hosts
   curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
   curl_setopt($ch, CURLOPT_URL, $url);
   curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);    // 要求结果为字符串且输出到屏幕上
   curl_setopt($ch, CURLOPT_HEADER, 0); // 不要http header 加快效率
   curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (compatible; MSIE 5.01; Windows NT 5.0)');
   curl_setopt($ch, CURLOPT_TIMEOUT, 15);
   $output = curl_exec($ch);
   curl_close($ch);
   return $output;
}

调用函数

function describeCdnService( $url_show, $action = 'RefreshObjectCaches' ){
    $access_key_id     = ACCESS_ID;
    $access_key_secret = ACCESS_SECRET;
       if(empty($access_key_id) || empty($access_key_secret)){
      $message = array(
         'status'   => 'failed',
         'reason'   => 'Access key Id or access key secret is invalid',
      );
      return json_encode($message);
       }
   $specialParameter = array(
        'AccessKeyId' => $access_key_id,
        'Action'      => $action,
        'ObjectPath'  => $url_show,
   );

    $parameter = setParameter( $specialParameter );
    $url       = getStringToSign( $parameter, $access_key_secret );
    $ret       = curl_get( $url );

   return $ret;
}

最后这个函数就是项目要调用的，此方法调用上面的三个方法

$url = DT_URL.'sell/show-'. $itemid .'.html';
describeCdnService( $url );

大功告成