How to: Exchange Messages with WCF Endpoints and Message Queuing Applications

Article
03/22/2010

You can integrate existing Message Queuing (MSMQ) applications with Windows Communication Foundation (WCF) applications by using the MSMQ integration binding to convert MSMQ messages to and from WCF messages. This allows you to call into MSMQ receiver applications from WCF clients as well as call into WCF services from MSMQ sender applications.

In this section, we explain how to use MsmqIntegrationBinding for queued communication between (1) a WCF client and an MSMQ application service written using System.Messaging and (2) an MSMQ application client and a WCF service.

For a complete sample that demonstrates how to call a MSMQ receiver application from a WCF client, see the Windows Communication Foundation to Message Queuing sample.

For a complete sample that demonstrates how to call a WCF service from a MSMQ client, see the Message Queuing to Windows Communication Foundation sample.

To create a WCF service that receives messages from a MSMQ client

Define an interface that defines the service contract for the WCF service that receives queued messages from a MSMQ sender application, as shown in the following example code.

<ServiceContract(Namespace:="http:'Microsoft.ServiceModel.Samples")> _
<ServiceKnownType(GetType(PurchaseOrder))> _
Public Interface IOrderProcessor
    <OperationContract(IsOneWay:=True, Action:="*")> _
    Sub SubmitPurchaseOrder(ByVal msg As MsmqMessage(Of PurchaseOrder))
End Interface

[ServiceContract(Namespace = "http://Microsoft.ServiceModel.Samples")]
[ServiceKnownType(typeof(PurchaseOrder))]
public interface IOrderProcessor
{
    [OperationContract(IsOneWay = true, Action = "*")]
    void SubmitPurchaseOrder(MsmqMessage<PurchaseOrder> msg);
}

Implement the interface and apply the ServiceBehaviorAttribute attribute to the class, as shown in the following example code.

Public Class OrderProcessorService
    Implements IOrderProcessor

    <OperationBehavior(TransactionScopeRequired:=True, TransactionAutoComplete:=True)> _
    Public Sub SubmitPurchaseOrder(ByVal ordermsg As MsmqMessage(Of PurchaseOrder)) Implements IOrderProcessor.SubmitPurchaseOrder
        Dim po As PurchaseOrder = ordermsg.Body
        Dim statusIndexer As New Random()
        po.Status = statusIndexer.Next(3)
        Console.WriteLine("Processing {0} ", po)
    End Sub
End Class

public class OrderProcessorService : IOrderProcessor
{
    [OperationBehavior(TransactionScopeRequired = true, TransactionAutoComplete = true)]
    public void SubmitPurchaseOrder(MsmqMessage<PurchaseOrder> ordermsg)
    {
        PurchaseOrder po = (PurchaseOrder)ordermsg.Body;
        Random statusIndexer = new Random();
        po.Status = (OrderStates)statusIndexer.Next(3);
        Console.WriteLine("Processing {0} ", po);
    }

    // Host the service within this EXE console application.
public static void Main()
{
    // Get base address from appsettings in configuration.
    Uri baseAddress = new Uri(ConfigurationManager.AppSettings["baseAddress"]);

    // Create a ServiceHost for the CalculatorService type and provide the base address.
    using (ServiceHost serviceHost = new ServiceHost(typeof(IOrderProcessor), baseAddress))
    {
    // Open the ServiceHostBase to create listeners and start listening for messages.
        serviceHost.Open();

    // The service can now be accessed.
        Console.WriteLine("The service is ready.");
        Console.WriteLine("The service is running in the following account: {0}", WindowsIdentity.GetCurrent().Name);
        Console.WriteLine("Press <ENTER> to terminate service.");
        Console.WriteLine();
        Console.ReadLine();

    // Close the ServiceHostBase to shutdown the service.
        serviceHost.Close();
    }
}

}

Create a configuration file that specifies the MsmqIntegrationBinding.

<configuration>
  <appSettings>
    <!-- use appSetting to configure MSMQ queue name -->
    <add key="orderQueueName" value=".\private$\Orders" />
    <add key="baseAddress" value="https://localhost:8000/ServiceModelSamples/Service" />
  </appSettings>
  <system.serviceModel>
    <services>
      <service 
        name="Microsoft.ServiceModel.Samples.OrderProcessorService" >
        <endpoint address="msmq.formatname:DIRECT=OS:.\private$\Orders"
                                binding="msmqIntegrationBinding"
                  bindingConfiguration="OrderProcessorBinding" 
                  contract="Microsoft.ServiceModel.Samples.IOrderProcessor">
        </endpoint>
      </service>
    </services>

    <bindings>
      <msmqIntegrationBinding>
        <binding name="OrderProcessorBinding" >
          <security mode="None" />
        </binding>
      </msmqIntegrationBinding>
    </bindings>

  </system.serviceModel >

</configuration>

Instantiate a ServiceHost object that uses the configured binding.

To create a WCF client that sends messages to a MSMQ receiver application

Define an interface that defines the service contract for the WCF client that sends queued messages to the MSMQ receiver, as shown in the following example code.

<System.ServiceModel.ServiceContractAttribute(Namespace:="http:'Microsoft.ServiceModel.Samples")> _
Public Interface IOrderProcessor
    <OperationContract(IsOneWay:=True, Action:="*")> _
    Sub SubmitPurchaseOrder(ByVal msg As MsmqMessage(Of PurchaseOrder))
end interface

Public Interface IOrderProcessorChannel
    Inherits IOrderProcessor, System.ServiceModel.IClientChannel
End Interface

[System.ServiceModel.ServiceContractAttribute(Namespace = "http://Microsoft.ServiceModel.Samples")]
public interface IOrderProcessor
{
    [OperationContract(IsOneWay = true, Action = "*")]
    void SubmitPurchaseOrder(MsmqMessage<PurchaseOrder> msg);
}

public interface IOrderProcessorChannel : IOrderProcessor, System.ServiceModel.IClientChannel
{
}

Define a client class that the WCF client uses to call the MSMQ receiver.

Dim binding As New MsmqIntegrationBinding()
Dim address As New EndpointAddress("msmq.formatname:DIRECT=OS:.\\private$\\Orders")
Dim channelFactory As New ChannelFactory(Of IOrderProcessor)(binding, address)
Dim channel As IOrderProcessor = channelFactory.CreateChannel()

Dim po As New PurchaseOrder()
po.customerId = "somecustomer.com"
po.poNumber = Guid.NewGuid().ToString()

Dim lineItem1 As New PurchaseOrderLineItem()
lineItem1.productId = "Blue Widget"
lineItem1.quantity = 54
lineItem1.unitCost = 29.99F

Dim lineItem2 = New PurchaseOrderLineItem()
lineItem2.productId = "Red Widget"
lineItem2.quantity = 890
lineItem2.unitCost = 45.89F

Dim lineItems(2) As PurchaseOrderLineItem
lineItems(0) = lineItem1
lineItems(1) = lineItem2

po.orderLineItems = lineItems

Dim ordermsg As MsmqMessage(Of PurchaseOrder) = New MsmqMessage(Of PurchaseOrder)(po)
Using scope As New TransactionScope(TransactionScopeOption.Required)
    channel.SubmitPurchaseOrder(ordermsg)
    scope.Complete()
End Using
Console.WriteLine("Order has been submitted:{0}", po)

MsmqIntegrationBinding binding = new MsmqIntegrationBinding();
EndpointAddress address = new EndpointAddress("msmq.formatname:DIRECT=OS:.\\private$\\Orders");
ChannelFactory<IOrderProcessor> channelFactory = new ChannelFactory<IOrderProcessor>(binding, address);
IOrderProcessor channel = channelFactory.CreateChannel();

PurchaseOrder po = new PurchaseOrder();
po.customerId = "somecustomer.com";
po.poNumber = Guid.NewGuid().ToString();

PurchaseOrderLineItem lineItem1 = new PurchaseOrderLineItem();
lineItem1.productId = "Blue Widget";
lineItem1.quantity = 54;
lineItem1.unitCost = 29.99F;

PurchaseOrderLineItem lineItem2 = new PurchaseOrderLineItem();
lineItem2.productId = "Red Widget";
lineItem2.quantity = 890;
lineItem2.unitCost = 45.89F;

po.orderLineItems = new PurchaseOrderLineItem[2];
po.orderLineItems[0] = lineItem1;
po.orderLineItems[1] = lineItem2;


MsmqMessage<PurchaseOrder> ordermsg = new MsmqMessage<PurchaseOrder>(po);
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required))
{
    channel.SubmitPurchaseOrder(ordermsg);
    scope.Complete();
}
Console.WriteLine("Order has been submitted:{0}", po);

Create a configuration that specifies use of the MsmqIntegrationBinding binding.

Dim binding As New MsmqIntegrationBinding("MyBindingConfig")

MsmqIntegrationBinding binding = new MsmqIntegrationBinding("MyBindingConfig");

<configuration>
    <system.serviceModel>

    <client>
      <endpoint  name="OrderResponseEndpoint" 
                address="msmq.formatname:DIRECT=OS:.\private$\Orders"
                binding="msmqIntegrationBinding"
                bindingConfiguration="OrderProcessorBinding" 
                contract="Microsoft.ServiceModel.Samples.IOrderProcessor">
      </endpoint>
    </client>

    <bindings>
      <msmqIntegrationBinding>
        <binding name="OrderProcessorBinding" >
          <security mode="None" />
        </binding>
      </msmqIntegrationBinding>
    </bindings>

  </system.serviceModel>

</configuration>

Create an instance of the client class and call the method defined by the message receiving service.

// Create the purchase order.
PurchaseOrder po = new PurchaseOrder();
po.customerId = "somecustomer.com";
po.poNumber = Guid.NewGuid().ToString();

PurchaseOrderLineItem lineItem1 = new PurchaseOrderLineItem();
lineItem1.productId = "Blue Widget";
lineItem1.quantity = 54;
lineItem1.unitCost = 29.99F;

PurchaseOrderLineItem lineItem2 = new PurchaseOrderLineItem();
lineItem2.productId = "Red Widget";
lineItem2.quantity = 890;
lineItem2.unitCost = 45.89F;

po.orderLineItems = new PurchaseOrderLineItem[2];
po.orderLineItems[0] = lineItem1;
po.orderLineItems[1] = lineItem2;

OrderProcessorClient client = new OrderProcessorClient("OrderResponseEndpoint");
MsmqMessage<PurchaseOrder> ordermsg = new MsmqMessage<PurchaseOrder>(po);
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required))
{
    client.SubmitPurchaseOrder(ordermsg);
    scope.Complete();
}

Console.WriteLine("Order has been submitted:{0}", po);

//Closing the client gracefully closes the connection and cleans up resources.
client.Close();

Console.WriteLine();
Console.WriteLine("Press <ENTER> to terminate client.");
Console.ReadLine();

How to: Exchange Messages with WCF Endpoints and Message Queuing Applications

To create a WCF service that receives messages from a MSMQ client

To create a WCF client that sends messages to a MSMQ receiver application

See Also

Tasks

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Other Resources

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