[WCF] Server did not recognize the value of HTTP Header SOAPAction:[some namespace]

I have a web service as the following :

   1: [WebService(Namespace = "http://app.trend.com/services/flowService/xml")]

   2: [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]

   3: public class Processor : System.Web.Services.WebService {

   4:    [WebMethod]

   5:    public Step GetStepInfo(string msgInstId, string stepId) {...}

   6:     //...

   7: }

For the Step class returned by this GetStepInfo() method, the definition is as the following :

   1: [Serializable]

   2: public class Step : BaseStep {

   3:    public StepNode() { }

   4:    

   5:    public string ID { get; set; }

   6:  

   7:    public string Name { get; set; }

   8:    //...

   9: }

And BaseStep:

   1: [Serializable]

   2: public class BaseStep{        

   3: public string Comments { get; set; }

   4: }

To consume this web service via WCF client, for some design concerns, I need to create a channel to operate the service, not just reference the service and invoking the method generated by the system. So I created a IProcessor interface and start to create certain methods…etc.

These is what I created and how I invoke the service :

   1: [ServiceContract(Namespace = "http://app.trend.com/services/flowService/xml")]

   2: public interface IProcessor{

   3:     //[OperationContract(Action = "http://app.trend.com/services/flowService/xml/GetStepInfo", ReplyAction="*")]

   4:     [OperationContract]

   5:     Trend.BPM.APPs.XmlFlowEngine.StepNode GetStepInfo(string msgInstId, string stepId);

   6:  

   7:     //[System.ServiceModel.OperationContractAttribute(Action = "http://app.trend.com/services/flowService/xml/StartCase", ReplyAction = "*")]

   8:     [OperationContract]

   9:     bool StartCase(string flowName, string msgId, string currentStepID, string owner, string action, string comments, string paramatersXml);

  10:  

  11:     //[System.ServiceModel.OperationContractAttribute(Action = "http://app.trend.com/services/flowService/xml/ReleaseCase", ReplyAction = "*")]

  12:     [OperationContract]

  13:     string ReleaseCase(string msgId, string stepID, string owner, string action, string comments, string paramaterXML);

  14:  

  15:     //[System.ServiceModel.OperationContractAttribute(Action = "http://app.trend.com/services/flowService/xml/GetNextApproverEx", ReplyAction = "*")]

  16:     [OperationContract]

  17:     bool GetNextApproverEx(string msgId, string flowName, string currentStep, string currentApprover, string category, out string nextApprover, out string newStep);

  18: }

And how I invoke the service:

   1: ChannelFactory<IXmlFlowEngine> channel = new ChannelFactory<IXmlFlowEngine>(new BasicHttpBinding(BasicHttpSecurityMode.None));

   2: var svc = channel.CreateChannel(new EndpointAddress(url));

Everything looks good until I actually run the program, I got the following error:

Server did not recognize the value of HTTP Header SOAPAction:http://app.trend.com/services/flowService/xml/IProcessor/GetStepInfo

I have this error because WCF serializer does not recognize the namespace and could not serialize/deserialize the message to objects. So I add namespace to my interface and Setp/StepBase class as following

   1: [ServiceContract(Namespace = "http://app.trend.com/services/flowService/xml", Name = "IProcessor")]

   2: public interface IXmlFlowEngine {

   3:     [OperationContract(Action = "http://app.trend.com/services/flowService/xml/GetStepInfo", ReplyAction="*")]

   4:     Trend.BPM.APPs.XmlFlowEngine.StepNode GetStepInfo(string msgInstId, string stepId);

   5:  

   6:     [System.ServiceModel.OperationContractAttribute(Action = "http://app.trend.com/services/flowService/xml/StartCase", ReplyAction = "*")]

   7:     bool StartCase(string flowName, string msgId, string currentStepID, string owner, string action, string comments, string paramatersXml);

   8:  

   9:     [System.ServiceModel.OperationContractAttribute(Action = "http://app.trend.com/services/flowService/xml/ReleaseCase", ReplyAction = "*")]

  10:     string ReleaseCase(string msgId, string stepID, string owner, string action, string comments, string paramaterXML);

  11:  

  12:     [System.ServiceModel.OperationContractAttribute(Action = "http://app.trend.com/services/flowService/xml/GetNextApproverEx", ReplyAction = "*")]

  13:     bool GetNextApproverEx(string msgId, string flowName, string currentStep, string currentApprover, string category, out string nextApprover, out string newStep);

  14: }

And explicitly specify the Name property on each class member

   1: [Serializable]

   2: [DataContract(Name="Step",Namespace="http://app.trend.com/services/flowService/xml")]

   3: public class Step : XmlFlowNode {

   4:     public StepNode() { }

   5:     [DataMember(Name="ID",EmitDefaultValue=false)]

   6:     public string ID { get; set; }

   7: }

   1: [Serializable]

   2: [DataContract(Name="StepBase",Namespace="http://app.trend.com/services/flowService/xml")]

   3: public class StepBase{

   4:     [DataMember(Name="Comments",EmitDefaultValue=false)]

   5:     public string Comments { get; set; }

   6: }

 

And this fixed the issue.