Question

我正在构建一个WCF路由器，我的客户端使用Reliable Sessions。在这种情况下，当客户端打开一个频道时，会发送一条消息（建立一个可靠的会话？）。其内容如下：

<s:Envelope xmlns:s="http://www.w3.org/2003/05/soap-envelope" xmlns:a="http://www.w3.org/2005/08/addressing">
  <s:Header>
    <a:Action s:mustUnderstand="1">http://docs.oasis-open.org/ws-rx/wsrm/200702/CreateSequence</a:Action>
    <a:MessageID>urn:uuid:1758f794-c5d3-4573-b252-7a07344cc257</a:MessageID>
    <a:To s:mustUnderstand="1">http://localhost:8010/RouterService</a:To>
  </s:Header>
  <s:Body>
    <CreateSequence xmlns="http://docs.oasis-open.org/ws-rx/wsrm/200702">
      <AcksTo>
        <a:Address>http://www.w3.org/2005/08/addressing/anonymous</a:Address>
      </AcksTo>
      <Offer>
        <Identifier>urn:uuid:64a12658-71d9-4967-88ec-9bb0610f7ecb</Identifier>
        <Endpoint>
          <a:Address>http://www.w3.org/2005/08/addressing/anonymous</a:Address>
        </Endpoint>
        <IncompleteSequenceBehavior>DiscardFollowingFirstGap</IncompleteSequenceBehavior>
      </Offer>
    </CreateSequence>
  </s:Body>
</s:Envelope>

这里的问题是标头不包含任何可用于查找将消息路由到的服务的信息。在Busatmante的路由器示例代码中，她通过向端点添加标头来解决这个问题：

  <client>
    <endpoint address="http://localhost:8010/RouterService" binding="ws2007HttpBinding"
      bindingConfiguration="wsHttp"
      contract="localhost.IMessageManagerService" >
      <headers>
        <Route xmlns="http://www.thatindigogirl.com/samples/2008/01" >http://www.thatindigogirl.com/samples/2008/01/IMessageManagerService</Route>
      </headers>
    </endpoint>
  </client>

打开可靠会话时，邮件包含此自定义标头。

<Route a:IsReferenceParameter="true" xmlns="http://www.thatindigogirl.com/samples/2008/01">http://www.thatindigogirl.com/samples/2008/01/IMessageManagerService</Route>

这很棒;但是，我需要以编程方式配置客户端。我认为ChannelFactory端点将有一个Header对象，我可以手动添加我的自定义标头。不幸的是它没有。所以我做了一些搜索，并通过实现IClientMessageInspector来添加我的头并将其作为行为添加到我的端点，找到一些推荐来扩展WCF。

public class ContractNameMessageInspector : IClientMessageInspector {

    private const string HEADER_NAME = "ContractName";
    private readonly string _ContractName;

    public ContractNameMessageInspector(string contractName) {
        _ContractName = contractName;
    }

    #region IClientMessageInspector Members

    public void AfterReceiveReply(ref Message reply, object correlationState) { }

    public object BeforeSendRequest(ref Message request, IClientChannel channel) {

        HttpRequestMessageProperty httpRequestMessage;
        object httpRequestMessageObject;

        if (request.Properties.TryGetValue(HttpRequestMessageProperty.Name, out httpRequestMessageObject)) {
            httpRequestMessage = httpRequestMessageObject as HttpRequestMessageProperty;
            if (httpRequestMessage != null && string.IsNullOrEmpty(httpRequestMessage.Headers[HEADER_NAME])) {
                httpRequestMessage.Headers[HEADER_NAME] = this._ContractName;
            }
        }
        else {
            httpRequestMessage = new HttpRequestMessageProperty();
            httpRequestMessage.Headers.Add(HEADER_NAME, this._ContractName);
            request.Properties.Add(HttpRequestMessageProperty.Name, httpRequestMessage);
        }
        return null;
    }

    #endregion
}

因此，当我的客户端进行服务调用时，该消息包含自定义标头，但建立可靠会话的消息仍然没有。

所以我的问题是;如何以可靠的会话消息包含它的方式以编程方式将自定义标头添加到端点？

非常感谢

Answer 1

想出来。虽然没有向EndpointAddress添加标头的属性或方法，但构造函数上有一个可选参数。

_Binding = bindingFactory.GetBinding(serviceUri, typeof(T));
AddressHeader header = AddressHeader.CreateAddressHeader("ContractName", "NameSpace", typeof (T).ToString());

_Address = new EndpointAddress(serviceUri, header);
_ChannelFactory = new ChannelFactory<T>(_Binding, _Address);

现在，当我收到建立可靠会话的消息时，它确实包含我的自定义标头。这种情况很有意义，因为消息检查器很可能只对分派的消息进行操作，而建立可靠会话的消息是由较低级别的WCF代码生成的。

Answer 2

这对我有用

   public TResult Invoke<TResult>(Func<TClient, TResult> func,MessageHeader header)
    {
        TClient client = default(TClient);
        var sw = new Stopwatch();
        try
        {
            sw.Start();
            using (client = _channelFactory.CreateChannel())
            {
               using (OperationContextScope contextScope = new OperationContextScope(client))
                {
                    OperationContext.Current.OutgoingMessageHeaders.Add(header);

                    return func.Invoke(client);
                }
            }
        }
        finally
        {
            CloseConnection(client);
            Instrument(this.GetType().Name, sw);
        }
    }

Answer 3

要以编程方式添加地址标头，请参阅MSDN的Address Headers，其中可以通过编程方式添加标头，例如：

var cl = new MyWCFClientContext();

var eab = new EndpointAddressBuilder(cl.Endpoint.Address);

eab.Headers.Add( AddressHeader.CreateAddressHeader("ClientIdentification", // Header Key
                                                    string.Empty,           // Namespace
                                                    "JabberwockyClient"));  // Header Value

cl.Endpoint.Address = eab.ToEndpointAddress();

以可编程会话的形式将自定义WCF标头添加到端点

3 个答案: