WCF服务的异常消息

原创地址：http://www.cnblogs.com/jfzhu/p/4055024.html                       

转载请注明出处

WCF Service发生异常的时候，客户端一般只能看见这样一个错误：“The server encountered an error processing the request”，而异常的类型和引起异常的代码都没有显示，究其原因是出于安全考虑。如果想要暴露这些异常信息的细节给客户端，只需要在服务器的配置文件上修改<serviceDebug includeExceptionDetailInFaults="true" />。

（一）SOAP WCF Service的异常

（1） 当serviceDebug includeExceptionDetailInFaults="false"

IDemoService.cs:

using System.ServiceModel;

namespace WCFDemo
{    
    [ServiceContract(Name = "IDemoService")]
    public interface IDemoService
    {
        [OperationContract]
        int Divide(int numerator, int denominator);
    }
}

DemoService.cs:

using System;
using System.ServiceModel.Activation;

namespace WCFDemo
{
    [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
    public class DemoService : IDemoService
    {
        public int Divide(int numerator, int denominator)
        {
            return numerator / denominator;
        }
    }
}

web.config

<?xml version="1.0"?> 
<configuration> 
    <system.web> 
      <compilation targetFramework="4.0" /> 
    </system.web>

    <system.serviceModel> 
      <services> 
        <service name="WCFDemo.DemoService" behaviorConfiguration="metaBehavior"> 
          <endpoint address="DemoService" binding="basicHttpBinding" contract="WCFDemo.IDemoService" /> 
          <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"></endpoint> 
          <host> 
            <baseAddresses> 
              <add baseAddress="http://localhost:8080"/> 
            </baseAddresses> 
          </host> 
        </service> 
      </services> 
        <behaviors> 
            <serviceBehaviors> 
                <behavior name="metaBehavior"> 
                    <serviceMetadata httpGetEnabled="true" /> 
                    <serviceDebug includeExceptionDetailInFaults="false" /> 
                </behavior> 
            </serviceBehaviors> 
        </behaviors> 
        <serviceHostingEnvironment multipleSiteBindingsEnabled="true" /> 
    </system.serviceModel> 
</configuration>

建立一个Windows Client，Form1.cs:

private void buttonCalculate_Click(object sender, EventArgs e) 
{ 
    DemoServiceReference.DemoServiceClient demoServiceClient = new DemoServiceReference.DemoServiceClient(); 
    textBoxResult.Text = demoServiceClient.Divide(Convert.ToInt32(textBoxNumerator.Text), Convert.ToInt32(textBoxDenominator.Text)).ToString(); 
} 

Client app.config

<?xml version="1.0" encoding="utf-8" ?> 
<configuration> 
    <system.serviceModel> 
        <bindings> 
            <basicHttpBinding> 
                <binding name="BasicHttpBinding_IDemoService" /> 
            </basicHttpBinding> 
        </bindings> 
        <client> 
            <endpoint address="http://169.254.14.147:8080/DemoService.svc/DemoService" 
                binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_IDemoService" 
                contract="DemoServiceReference.IDemoService" name="BasicHttpBinding_IDemoService" /> 
        </client> 
    </system.serviceModel> 
</configuration>

在正常情况下的消息为：

Request Body:

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
  <s:Body>
    <Divide xmlns="http://tempuri.org/">
      <numerator>100</numerator>
      <denominator>10</denominator>
    </Divide>
  </s:Body>
</s:Envelope>

Response Body:

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
  <s:Body>
    <DivideResponse xmlns="http://tempuri.org/">
      <DivideResult>10</DivideResult>
    </DivideResponse>
  </s:Body>
</s:Envelope>

在发生异常时：

Request Header:

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
  <s:Body>
    <Divide xmlns="http://tempuri.org/">
      <numerator>100</numerator>
      <denominator>0</denominator>
    </Divide>
  </s:Body>
</s:Envelope>

Response Body:

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
  <s:Body>
    <s:Fault>
      <faultcode xmlns:a="http://schemas.microsoft.com/net/2005/12/windowscommunicationfoundation/dispatcher">a:InternalServiceFault</faultcode>
      <faultstring xml:lang="en-US">The server was unable to process the request due to an internal error.  For more information about the error, either turn on IncludeExceptionDetailInFaults (either from ServiceBehaviorAttribute or from the &lt;serviceDebug&gt; configuration behavior) on the server in order to send the exception information back to the client, or turn on tracing as per the Microsoft .NET Framework SDK documentation and inspect the server trace logs.</faultstring>
    </s:Fault>
  </s:Body>
</s:Envelope>

 

（2）当serviceDebug includeExceptionDetailInFaults="true"

可以看到异常的消息为”Attempted to divide by zero.”

response body:

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
  <s:Body>
    <s:Fault>
      <faultcode xmlns:a="http://schemas.microsoft.com/net/2005/12/windowscommunicationfoundation/dispatcher">a:InternalServiceFault</faultcode>
      <faultstring xml:lang="en-US">Attempted to divide by zero.</faultstring>
      <detail>
        <ExceptionDetail xmlns="http://schemas.datacontract.org/2004/07/System.ServiceModel" xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
          <HelpLink i:nil="true"/>
          <InnerException i:nil="true"/>
          <Message>Attempted to divide by zero.</Message>
          <StackTrace>
            at WCFDemo.DemoService.Divide(Int32 numerator, Int32 denominator)&#xD;
            at SyncInvokeDivide(Object , Object[] , Object[] )&#xD;
            at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]&amp; outputs)&#xD;
            at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc&amp; rpc)&#xD;
            at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc&amp; rpc)&#xD;
            at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage31(MessageRpc&amp; rpc)&#xD;
            at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)
          </StackTrace>
          <Type>System.DivideByZeroException</Type>
        </ExceptionDetail>
      </detail>
    </s:Fault>
  </s:Body>
</s:Envelope>

（二）JSON WCF Service的异常

（1） serviceDebug includeExceptionDetailInFaults="false"

IDemoJsonService.cs:

using System.ServiceModel;

namespace WCFDemo
{
    [ServiceContract(Namespace = "IDemoJsonService")]
    public interface IDemoJsonService
    {
        [OperationContract]
        int Divide(int numerator, int denominator);
    }
}

DemoJsonService.cs

using System.ServiceModel;
using System.ServiceModel.Activation;
using System.ServiceModel.Web;

namespace WCFDemo
{

    [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
    public class DemoJsonService : IDemoJsonService
    {
        [WebGet(UriTemplate="Divide?numerator={numerator}&denominator={denominator}", ResponseFormat=WebMessageFormat.Json)]
        public int Divide(int numerator, int denominator)
        {
            return numerator / denominator;
        }
    }
}

 

web.config

<?xml version="1.0"?> 
<configuration> 
    <system.web> 
      <compilation debug="true" targetFramework="4.0" /> 
    </system.web> 
    <system.serviceModel> 
      <services> 
        <service name="WCFDemo.DemoService" behaviorConfiguration="metaBehavior"> 
          <endpoint address="DemoService" binding="basicHttpBinding" contract="WCFDemo.IDemoService" />          
          <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"></endpoint> 
        </service> 
        <service name="WCFDemo.DemoJsonService" behaviorConfiguration="metaBehavior"> 
          <endpoint address="DemoJsonService" binding="webHttpBinding" contract="WCFDemo.IDemoJsonService" behaviorConfiguration="WCFDemo.DemoJsonService.endpointBehavior" /> 
          <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"></endpoint> 
        </service> 
      </services> 
        <behaviors> 
            <serviceBehaviors> 
                <behavior name="metaBehavior"> 
                    <serviceMetadata httpGetEnabled="true" /> 
                    <serviceDebug includeExceptionDetailInFaults="false" /> 
                </behavior> 
            </serviceBehaviors> 
          <endpointBehaviors> 
            <behavior name="WCFDemo.DemoJsonService.endpointBehavior"> 
              <webHttp helpEnabled="true"/> 
            </behavior> 
          </endpointBehaviors> 
        </behaviors> 
        <serviceHostingEnvironment multipleSiteBindingsEnabled="true" /> 
    </system.serviceModel> 
</configuration>

正常情况下：

发生异常时：

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
  <head> 
    <title>Request Error</title> 
    <style>BODY { color: #000000; background-color: white; font-family: Verdana; margin-left: 0px; margin-top: 0px; } #content { margin-left: 30px; font-size: .70em; padding-bottom: 2em; } A:link { color: #336699; font-weight: bold; text-decoration: underline; } A:visited { color: #6699cc; font-weight: bold; text-decoration: underline; } A:active { color: #336699; font-weight: bold; text-decoration: underline; } .heading1 { background-color: #003366; border-bottom: #336699 6px solid; color: #ffffff; font-family: Tahoma; font-size: 26px; font-weight: normal;margin: 0em 0em 10px -20px; padding-bottom: 8px; padding-left: 30px;padding-top: 16px;} pre { font-size:small; background-color: #e5e5cc; padding: 5px; font-family: Courier New; margin-top: 0px; border: 1px #f0f0e0 solid; white-space: pre-wrap; white-space: -pre-wrap; word-wrap: break-word; } table { border-collapse: collapse; border-spacing: 0px; font-family: Verdana;} table th { border-right: 2px white solid; border-bottom: 2px white solid; font-weight: bold; background-color: #cecf9c;} table td { border-right: 2px white solid; border-bottom: 2px white solid; background-color: #e5e5cc;}</style> 
  </head> 
  <body> 
    <div id="content"> 
      <p class="heading1">Request Error</p> 
      <p xmlns="">The server encountered an error processing the request. Please see the <a rel="help-page" href="http://169.254.14.147:8080/DemoJsonService.svc/DemoJsonService/help">service help page</a> for constructing valid requests to the service.</p> 
    </div> 
  </body> 
</html>

（2）当serviceDebug includeExceptionDetailInFaults="true"

web.config

<?xml version="1.0"?> 
<configuration> 
    <system.web> 
      <compilation debug="true" targetFramework="4.0" /> 
    </system.web> 
    <system.serviceModel> 
      <services> 
        <service name="WCFDemo.DemoService" behaviorConfiguration="metaBehavior"> 
          <endpoint address="DemoService" binding="basicHttpBinding" contract="WCFDemo.IDemoService" />          
          <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"></endpoint> 
        </service> 
        <service name="WCFDemo.DemoJsonService" behaviorConfiguration="metaBehavior"> 
          <endpoint address="DemoJsonService" binding="webHttpBinding" contract="WCFDemo.IDemoJsonService" behaviorConfiguration="WCFDemo.DemoJsonService.endpointBehavior" /> 
          <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"></endpoint> 
        </service> 
      </services> 
        <behaviors> 
            <serviceBehaviors> 
                <behavior name="metaBehavior"> 
                    <serviceMetadata httpGetEnabled="true" /> 
                    <serviceDebug includeExceptionDetailInFaults="true" /> 
                </behavior> 
            </serviceBehaviors> 
          <endpointBehaviors> 
            <behavior name="WCFDemo.DemoJsonService.endpointBehavior"> 
              <webHttp helpEnabled="true"/> 
            </behavior> 
          </endpointBehaviors> 
        </behaviors> 
        <serviceHostingEnvironment multipleSiteBindingsEnabled="true" /> 
    </system.serviceModel> 
</configuration> 

<?xml version="1.0" encoding="utf-8"?> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
  <head> 
    <title>Request Error</title> 
    <style>BODY { color: #000000; background-color: white; font-family: Verdana; margin-left: 0px; margin-top: 0px; } #content { margin-left: 30px; font-size: .70em; padding-bottom: 2em; } A:link { color: #336699; font-weight: bold; text-decoration: underline; } A:visited { color: #6699cc; font-weight: bold; text-decoration: underline; } A:active { color: #336699; font-weight: bold; text-decoration: underline; } .heading1 { background-color: #003366; border-bottom: #336699 6px solid; color: #ffffff; font-family: Tahoma; font-size: 26px; font-weight: normal;margin: 0em 0em 10px -20px; padding-bottom: 8px; padding-left: 30px;padding-top: 16px;} pre { font-size:small; background-color: #e5e5cc; padding: 5px; font-family: Courier New; margin-top: 0px; border: 1px #f0f0e0 solid; white-space: pre-wrap; white-space: -pre-wrap; word-wrap: break-word; } table { border-collapse: collapse; border-spacing: 0px; font-family: Verdana;} table th { border-right: 2px white solid; border-bottom: 2px white solid; font-weight: bold; background-color: #cecf9c;} table td { border-right: 2px white solid; border-bottom: 2px white solid; background-color: #e5e5cc;}</style> 
  </head> 
  <body> 
    <div id="content"> 
      <p class="heading1">Request Error</p> 
      <p xmlns="">The server encountered an error processing the request. Please see the <a rel="help-page" href="http://169.254.14.147:8080/DemoJsonService.svc/DemoJsonService/help">service help page</a> for constructing valid requests to the service. The exception message is 'Attempted to divide by zero.'. See server logs for more details. The exception stack trace is: </p> 
      <p>   at WCFDemo.DemoJsonService.Divide(Int32 numerator, Int32 denominator) 
   at SyncInvokeDivide(Object , Object[] , Object[] ) 
   at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]&amp; outputs) 
   at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc&amp; rpc) 
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc&amp; rpc) 
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage31(MessageRpc&amp; rpc) 
   at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)</p> 
    </div> 
  </body> 
</html>

（三）总结

出于安全考虑，WCF Server不会暴露异常的详细信息，如果想看到这一信息，需要在服务器上将配置文件修改为<serviceDebug includeExceptionDetailInFaults="true" />。