错误返回的具体内容

502 Bad Gateway

The proxy server received an invalid response from an upstream server. Sorry for the inconvenience.

Please report this message and include the following information to us.

Thank you very much!

URL:	http://a1.easemob.com:81/1139161222115946/mygamebox/message/
Server:	ops-ali-hk-proxy1
Date:	2017/04/02 00:30:52

---

Powered by Tengine/2.2.0

 
执行调用的c#接口
 
public class RestClient
    {
        public string EndPoint { get; set; }
        public HttpVerb Method { get; set; }
        public string ContentType { get; set; }
        public string PostData { get; set; }

        public RestClient()
        {
            EndPoint = "";
            Method = HttpVerb.GET;
            ContentType = "application/x-www-form-urlencoded";
            PostData = "";
        }
        public RestClient(string endpoint)
        {
            EndPoint = endpoint;
            Method = HttpVerb.GET;
            ContentType = "application/x-www-form-urlencoded";
            PostData = "";
        }
        public RestClient(string endpoint, HttpVerb method)
        {
            EndPoint = endpoint;
            Method = method;
            ContentType = "application/x-www-form-urlencoded";
            PostData = "";
        }

        public RestClient(string endpoint, HttpVerb method, string postData)
        {
            EndPoint = endpoint;
            Method = method;
            ContentType = "application/x-www-form-urlencoded";
            PostData = postData;
        }

        long k = 0;
        public string MakeRequest(string token)
        {
            if (k > 90000) { k = 0; }
            k++;
            return MakeRequest(""+k, token);
        }

        public string MakeRequest(string parameters,string token)
        {
            var request = (HttpWebRequest)WebRequest.Create(EndPoint + parameters);
            if(token.Length>0)
            {
                request.Headers["Authorization"] = "Bearer " + token;
            }
            request.Method = Method.ToString();
            request.ContentLength = 0;
            request.ContentType = ContentType;
            request.Timeout = 2000;
            request.ReadWriteTimeout = 1000;

            if (!string.IsNullOrEmpty(PostData) && Method == HttpVerb.POST)
            {
                var encoding = new UTF8Encoding();
                var bytes = Encoding.GetEncoding("iso-8859-1").GetBytes(PostData);
                request.ContentLength = bytes.Length;

                using (var writeStream = request.GetRequestStream())
                {
                    writeStream.Write(bytes, 0, bytes.Length);
                }
            }

            using (var response = (HttpWebResponse)request.GetResponse())
            {
                var responseValue = string.Empty;

                if (response.StatusCode != HttpStatusCode.OK)
                {
                    var message = String.Format("Request failed. Received HTTP {0}", response.StatusCode);
                    throw new ApplicationException(message);
                }

                // grab the response
                using (var responseStream = response.GetResponseStream())
                {
                    if (responseStream != null)
                        using (var reader = new StreamReader(responseStream))
                        {
                            responseValue = reader.ReadToEnd();
                        }
                }

                return responseValue;
            }
        }

    }
 
**  有做parameters自增加来区分缓存