简短版本:在
AJAX启用的WCF服务中抛出异常(除了打开门并发回所有异常详细信息之外),是否有/有什么建议的方式将错误详细信息返回给客户端?
长版本:
我有一个相对简单的启用AJAX的WCF服务,我使用默认服务代理从客户端调用.我在下面提供了代码片段,但我不相信代码本身有什么问题.
我的问题是,如果我在服务中抛出异常,返回给客户端的错误对象总是通用的:
{ "ExceptionDetail":null,"ExceptionType":null,"Message":"The server was unable to process the request..." "StackTrace":null }
理想情况下,我想在客户端上显示不同的错误消息,具体取决于出错.
一个选择是允许在WCF故障中的异常,这将为我提供完整的堆栈跟踪和一切,但我感谢安全性的关注,这实际上比我需要更多的信息.我可以做的只是能够发回一个描述问题或某事的字符串,但我没有看到一种方法来做到这一点.
我的服务代码:
[ServiceContract(Namespace = "MyNamespace")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class MyService { [OperationContract] public void DoStuff(string param1,string etc) { //Do some stuff that maybe causes an exception } }
在客户端上
MyNamespace.MyService.DoStuff( param1,etc,function() { alert("success"); },HandleError);
解决方法
编辑:用适当的自定义json错误处理程序更新了该帖子
快速但非优先的方式.
<serviceDebug includeExceptionDetailInFaults="true"/>
在您的服务行为将给您所需的所有细节.
好的方式
应用程序的所有异常都将转换为JsonError并使用DataContractJsonSerializer进行序列化. Exception.Message直接使用. FaultExceptions提供了FaultCode,其他异常处理为未知的faultcode -1.
使用HTTP状态代码400发送FaultException,其他异常是HTTP代码500 – 内部服务器错误.这不是必需的,因为faultcode可以用来决定是否和未知的错误.这在我的应用程序是方便的
错误处理程序
internal class CustomErrorHandler : IErrorHandler { public bool HandleError(Exception error) { //Tell the system that we handle all errors here. return true; } public void ProvideFault(Exception error,System.ServiceModel.Channels.MessageVersion version,ref System.ServiceModel.Channels.Message fault) { if (error is FaultException<int>) { FaultException<int> fe = (FaultException<int>)error; //Detail for the returned value int faultCode = fe.Detail; string cause = fe.Message; //The json serializable object JsonError msErrObject = new JsonError { Message = cause,FaultCode = faultCode }; //The fault to be returned fault = Message.CreateMessage(version,"",msErrObject,new DataContractJsonSerializer(msErrObject.GetType())); // tell WCF to use JSON encoding rather than default XML WebBodyFormatMessageProperty wbf = new WebBodyFormatMessageProperty(WebContentFormat.Json); // Add the formatter to the fault fault.Properties.Add(WebBodyFormatMessageProperty.Name,wbf); //Modify response HttpResponseMessageProperty rmp = new HttpResponseMessageProperty(); // return custom error code,400. rmp.StatusCode = System.Net.HttpStatusCode.BadRequest; rmp.StatusDescription = "Bad request"; //Mark the jsonerror and json content rmp.Headers[HttpResponseHeader.ContentType] = "application/json"; rmp.Headers["jsonerror"] = "true"; //Add to fault fault.Properties.Add(HttpResponseMessageProperty.Name,rmp); } else { //Arbitraty error JsonError msErrObject = new JsonError { Message = error.Message,FaultCode = -1}; // create a fault message containing our FaultContract object fault = Message.CreateMessage(version,new DataContractJsonSerializer(msErrObject.GetType())); // tell WCF to use JSON encoding rather than default XML var wbf = new WebBodyFormatMessageProperty(WebContentFormat.Json); fault.Properties.Add(WebBodyFormatMessageProperty.Name,wbf); //Modify response var rmp = new HttpResponseMessageProperty(); rmp.Headers[HttpResponseHeader.ContentType] = "application/json"; rmp.Headers["jsonerror"] = "true"; //Internal server error with exception mesasage as status. rmp.StatusCode = System.Net.HttpStatusCode.InternalServerError; rmp.StatusDescription = error.Message; fault.Properties.Add(HttpResponseMessageProperty.Name,rmp); } } #endregion }
internal class AddErrorHandlerBehavior : WebHttpBehavior { protected override void AddServerErrorHandlers(ServiceEndpoint endpoint,EndpointDispatcher endpointDispatcher) { base.AddServerErrorHandlers(endpoint,endpointDispatcher); //Remove all other error handlers endpointDispatcher.ChannelDispatcher.ErrorHandlers.Clear(); //Add our own endpointDispatcher.ChannelDispatcher.ErrorHandlers.Add(new CustomErrorHandler()); } }
json错误数据合同
[DataContractFormat] public class JsonError { [DataMember] public string Message { get; set; } [DataMember] public int FaultCode { get; set; } }
使用错误处理程序
自托管
ServiceHost wsHost = new ServiceHost(new Webservice1(),new Uri("http://localhost/json")); ServiceEndpoint wsEndpoint = wsHost.AddServiceEndpoint(typeof(IWebservice1),new WebHttpBinding(),string.Empty); wsEndpoint.Behaviors.Add(new AddErrorHandlerBehavior());
App.config中
<extensions> <behaviorExtensions> <add name="errorHandler" type="WcfServiceLibrary1.ErrorHandlerElement,WcfServiceLibrary1" /> </behaviorExtensions> </extensions>