Como: fazer intercâmbio de mensagens com pontos de extremidade do WCF e aplicativos de enfileiramento de mensagens

  • Artigo

Você pode integrar aplicativos de MSMQ (Enfileiramento de Mensagens) existentes a aplicativos do WCF (Windows Communication Foundation) usando a associação de integração MSMQ para converter mensagens MSMQ de e para mensagens WCF. Isso permite chamar aplicativos receptores MSMQ de clientes WCF, bem como serviços WCF de aplicativos de remetente MSMQ.

Nesta seção, explicamos como usar MsmqIntegrationBinding para comunicação enfileirada entre (1) um cliente WCF e um serviço de aplicativo MSMQ escrito usando System.Messaging e (2) um cliente de aplicativo MSMQ e um serviço WCF.

Para obter um exemplo completo que demonstra como chamar um aplicativo receptor MSMQ de um cliente WCF, consulte a amostra de Enfileiramento de Mensagens do Windows Communication Foundation.

Para obter um exemplo completo que demonstra como chamar um serviço WCF de um cliente MSMQ, consulte a amostra de Enfileiramento de Mensagens para o Windows Communication Foundation.

Para criar um serviço WCF que recebe mensagens de um cliente MSMQ

  1. Defina uma interface que define o contrato de serviço para o serviço WCF que recebe mensagens enfileiradas de um aplicativo remetente MSMQ, conforme mostrado no código de exemplo a seguir.

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

    <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

  2. Implemente a interface e aplique o atributo ServiceBehaviorAttribute à classe, conforme mostrado no código de exemplo a seguir.

    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();
    }
}
}

    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

  3. Crie um arquivo de configuração que especifica o MsmqIntegrationBinding.

  4. Instancie um objeto ServiceHost que usa a associação configurada.

Para criar um cliente WCF que envia mensagens para um aplicativo receptor MSMQ

  1. Defina uma interface que define o contrato de serviço para o cliente WCF que envia mensagens enfileiradas para o receptor MSMQ, conforme mostrado no código de exemplo a seguir.

    [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
{
}

    <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

  2. Defina uma classe cliente que o cliente WCF usa para chamar o receptor MSMQ.

    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);

    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(1) 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)

  3. Crie uma configuração que especifica o uso da associação MsmqIntegrationBinding.

    MsmqIntegrationBinding binding = new MsmqIntegrationBinding("MyBindingConfig");

    Dim binding As New MsmqIntegrationBinding("MyBindingConfig")

  4. Crie uma instância da classe cliente e chame o método definido pelo serviço de recebimento da mensagem.

    // 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();

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