c# - 使用 NetTcpBinding 的双工通信 - ContractFilter 不匹配？

Question

我在使用 NetTcpBinding 在客户端和服务器之间打开双工通信 channel 方面取得了缓慢而稳定的进展。 (仅供引用，您可以观察我的新手进度 here 和 here!)

我现在已经成功连接到我的服务器，通过服务器的防火墙，客户端可以向服务器发出请求。

然而，另一方面，事情并不那么令人愉快。在我自己的机器上测试时它工作正常，但是在互联网上测试时，当我尝试从服务器端发起回调时，我得到一个错误:

The message with Action 'http://MyWebService/IWebService/HelloWorld' cannot be
processed at the receiver, 
due to a ContractFilter mismatch at the EndpointDispatcher. 
This may be because of either a contract mismatch (mismatched Actions between 
sender and receiver) 
or a binding/security mismatch between the sender and the receiver.  
Check that sender and receiver have the same contract and the same binding 
(including security requirements, e.g. Message, Transport, None).

以下是代码的一些关键位。一、网页界面:

[ServiceContract(Namespace = "http://MyWebService", SessionMode = SessionMode.Required, CallbackContract = typeof(ISiteServiceExternal))]
public interface IWebService {
  [OperationContract]
  void Register(long customerID);
}

public interface ISiteServiceExternal {
  [OperationContract]
  string HelloWorld();
}

这是 IWebService 的实现:

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall)]
class WebService : IWebService {
  void IWebService.Register(long customerID) {
    Console.WriteLine("customer {0} registering", customerID);
    var callbackService = OperationContext.Current.GetCallbackChannel<ISiteServiceExternal>();
    RegisterClient(customerID, callbackService);
    Console.WriteLine("customer {0} registered", customerID);
  }
}

然后，在客户端(我在不知不觉中摆弄这些属性):

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession, Namespace="http://MyWebService")]
class SiteServer : IWebServiceCallback {
  string IWebServiceCallback.HelloWorld() {
return "Hello World!";
  }
  ...
}

那么我做错了什么？

编辑: 添加 app.config 代码。来自服务器:

<system.serviceModel>
  <diagnostics>
    <messageLogging logMalformedMessages="true" logMessagesAtServiceLevel="true"
        logMessagesAtTransportLevel="true" logEntireMessage="true" maxMessagesToLog="1000" maxSizeOfMessageToLog="524288" />
  </diagnostics>
  <behaviors>
    <serviceBehaviors>
      <behavior name="mex">
        <serviceDebug includeExceptionDetailInFaults="true"/>
        <serviceMetadata/>
      </behavior>
    </serviceBehaviors>
  </behaviors>
  <services>
    <service name ="MyWebService.WebService" behaviorConfiguration="mex">
      <endpoint address="net.tcp://localhost:8000" binding="netTcpBinding" contract="MyWebService.IWebService"
                bindingConfiguration="TestBinding" name="MyEndPoint"></endpoint>
      <endpoint address ="mex"
                binding="mexTcpBinding"
                name="MEX"
                contract="IMetadataExchange"/>
      <host>
        <baseAddresses>
          <add baseAddress="net.tcp://localhost:8000"/>
        </baseAddresses>
      </host>
    </service>
  </services>
  <bindings>
    <netTcpBinding>
      <binding name="TestBinding" maxBufferPoolSize="524288" maxReceivedMessageSize="65536" portSharingEnabled="false">
        <readerQuotas maxDepth="32" maxStringContentLength ="8192" maxArrayLength ="16384" maxBytesPerRead="4096" maxNameTableCharCount="16384"/>
        <security mode="None"/>
      </binding>
    </netTcpBinding>
  </bindings>
</system.serviceModel>

在客户端:

<system.serviceModel>
  <bindings>
    <netTcpBinding>
      <binding name="MyEndPoint" closeTimeout="00:01:00" openTimeout="00:01:00"
          receiveTimeout="00:10:00" sendTimeout="00:01:00" transactionFlow="false"
          transferMode="Buffered" transactionProtocol="OleTransactions"
          hostNameComparisonMode="StrongWildcard" listenBacklog="10"
          maxBufferPoolSize="524288" maxBufferSize="65536" maxConnections="10"
          maxReceivedMessageSize="65536">
        <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384"
            maxBytesPerRead="4096" maxNameTableCharCount="16384" />
        <reliableSession ordered="true" inactivityTimeout="00:10:00"
            enabled="false" />
        <security mode="None">
          <transport clientCredentialType="Windows" protectionLevel="EncryptAndSign">
            <extendedProtectionPolicy policyEnforcement="Never" />
          </transport>
          <message clientCredentialType="Windows" />
        </security>
      </binding>
    </netTcpBinding>
  </bindings>
  <client>
    <endpoint address="net.tcp://mydomain.gotdns.com:8000/" binding="netTcpBinding"
        bindingConfiguration="MyEndPoint" contract="IWebService" name="MyEndPoint" />
  </client>
</system.serviceModel>

Answer 1

感谢@Allon Guralnek，他帮助我注意到问题所在:

在服务器端我有:

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall)]
class WebService : IWebService { ... }

在客户端我有:

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession, Namespace="http://MyWebService")]
class SiteServer : IWebServiceCallback { ... }

冲突发生在 PerCall 和 PerSession 之间。我刚刚将服务器端更改为 PerSession，而且 - 休斯顿，我们已经起飞了!

现在，要让它与安全性一起工作...请观看 SO 以了解我的 WCF 学习曲线中的下一个激动人心的部分! :)