如何使用REST服务处理客户端-服务器应用程序中的错误？

Question

题

1）使用REST服务时如何处理客户端-服务器应用程序中的错误？ 有人可以帮我提供示例代码，什么是处理以下代码中错误消息的最佳方法。 例如，在创建服务的情况下，如何在客户端和/或服务器端捕获异常？

2）在出现错误和成功的情况下，如何将用户转发到其他页面？

---

客户

 $('#btnSignup').click(function(){ 
            var user = {"id": 10, "firstName": $('#firstName').val(), "lastName":       $('#lastName').val(), "age": 69, "freeText": "55555", "weight": 55};

            $.ajax({
            type: "POST",
            contentType: "application/json",
            url: "http://localhost:8080/test/webresources/entity.user/",
            dataType: "json",
            data: JSON.stringify(user),

            success: function(response) {
               $('#myModal').modal('hide');
            },
            error: function(data) {
                alert('addUser error: ');
            }
        });

    }); 

REST服务

@Stateless
@Path("entity.user")

public class UsersFacadeREST extends AbstractFacade<Users> {
@PersistenceContext(unitName = "testPU")
private EntityManager em;

public UsersFacadeREST() {
    super(Users.class);
}

@POST
@Override
@Consumes({"application/xml", "application/json"})
public void create(Users entity) {
    super.create(entity);
}

Answer 1

只需2美分，那么您可以定义一个Result Object，您可以在每次休息电话后返回它

Class Result{
   private String statusCode;
   private String statusDescription;

}

在豆

@POST
@Override
@Consumes({"application/xml", "application/json"})
@Produces({ "application/json"})
public Result create(Users entity) {
  Result result = new Result();
  try{
    super.create(entity);
   result.setStatus("200");
   result.setStatusDescriptions("Success");
   }catch(Exception) {
        result.setStatus("500");
        result.setStatusDescriptions("Fail");
   }

  return result;  // Return this as Json 
}

您稍后可以使用jquery解析HTML中的响应，并根据“状态”处理流程

Answer 2

1）在服务器端创建自己的RESTException。

2）每当您回应该异常时； 在HTTP标头中添加该异常消息。

3）在HTTP协议中，在服务器端使用Exceptions头中的errorCode && errorMessage并将其在客户端解码，以在客户端显示有关该异常的有意义的数据。

HTTP Status: 500 - Internal Server Error
Response Headers:
Date=Wed, 09 Jan 2013 13:41:15 GMT
Server=Apache/2.2.17 (Unix) mod_ssl/2.2.17 OpenSSL/0.9.8e-fips-rhel5 mod_jk/1.2.28

errorCode=4567
errorMessage=invalid conference passcode

Accept-Charset=big5, big5-hkscs, compound_text, euc-jp, euc-kr, gb18030, gb2312, gbk,      ibm-thai, ibm00858, ibm01140, ibm01141, ibm01142, ibm01143, ibm01144, ibm01145, ibm01146, ibm874, x-ibm875, x-ibm921, x-ibm922, x-ibm930, x-ibm933, x-ibm935, x-ibm937, x-ibm939, x- x-windows-50221, x-windows-874, x-windows-949, x-windows-950, x-windows-iso2022jp
Content-Length=6406
Connection=close
Content-Type=application/xml
Response Body:
4567: invalid conference passcode
com.xxx.exceptions.InvalidPasscodeException invalid conference passcode
    at com.xxx.dao.impl.context.multipleconfs.ResLessConfDao.validatePasscode(ResLessConfDao.java:754)
    at 

下面是使用C＃客户端代码将请求发送到服务器的示例； 这具有错误处理机制。

    public static bool sendRequest(string requestURL, HTTPRequestMethod requestMethod,
        NetworkCredential m_netCred, String xml, ErrorResponse m_objErrorResponse)
    {
        try
        {
            HttpWebRequest request = WebRequest.Create(requestURL) as HttpWebRequest;
            request.PreAuthenticate = true;
            request.Credentials = m_netCred;
            request.Method = requestMethod.ToString();
            request.AllowAutoRedirect = false;
            request.ReadWriteTimeout = 100000;
            request.ContentLength = xml.Length;
            request.ContentType = "application/xml; encoding='utf-8'";
            Debug.WriteLine("XML: {0}", xml);
            StreamWriter postStream = new StreamWriter(request.GetRequestStream(), System.Text.Encoding.ASCII);
            postStream.Write(xml);
            postStream.Close();
            WebResponse response = request.GetResponse();
            response.Close();
        }
        catch (WebException webex)
        {
            var response = webex.Response as HttpWebResponse;
            int errCode = 0;
            if (response != null)
            {
                errCode = (int)response.StatusCode;
                Debug.WriteLine("HTTP Status Code: " + (int)response.StatusCode);
                if ((int)response.StatusCode != 500) //Other errors
                {
                    m_objErrorResponse.UpdateErrorResponse(errCode.ToString(), response.StatusCode.ToString(), "");
                }
                else
                {
                    m_objErrorResponse.UpdateErrorResponse(errCode.ToString(), response.StatusCode.ToString(),
                        response.Headers.ToString().Split('\n')[1].Substring(14).Trim());
                }
            }
            return false;
        }
        return true;
    }
}

Spring MVC REST异常处理第1部分
Spring MVC REST异常处理第2部分