Procédure : créer un service qui exige des sessions

Les sessions créent un état partagé entre deux ou plusieurs points de terminaison activant des fonctions utiles telles que les rappels, la sécurité en cascade et des associations entre clients et instances de service. Pour plus d’informations sur les sessions dans les applications Windows Communication Foundation (WCF), consultez Utilisation de sessions.

Pour spécifier qu'un contrat requiert que sa liaison prenne en charge des sessions

  1. Créez un contrat de service qui contient au moins une opération. Pour obtenir un exemple de création de contrat de service, consultez Comment : Définir un contrat de service.

  2. Modifiez le System.ServiceModel.ServiceContractAttribute qui déclare le contrat en affectant à la propriété ServiceContractAttribute.SessionMode la valeur :

  3. Configurez votre point de terminaison de service pour utiliser une liaison qui prend en charge des sessions. L'exemple de configuration suivant montre l'utilisation de System.ServiceModel.WSDualHttpBinding, qui prend en charge une session de messagerie WS-Reliable.

    <appSettings>
      <!-- use appSetting to configure base address provided by host -->
      <add key="baseAddress" value="http://localhost:8080/ServiceMetadata" />
    </appSettings>
    <system.serviceModel>
      <services>
        <service 
          name="Microsoft.WCF.Documentation.DuplexHello"
          behaviorConfiguration="mex"
        >
          <endpoint
            address="/DuplexService"
            binding="wsDualHttpBinding"
            contract="Microsoft.WCF.Documentation.IDuplexHello"
           />
          <endpoint
            address=""
            binding="mexHttpBinding"
            contract="IMetadataExchange"
          />
        </service>
      </services>
      <behaviors>
        <serviceBehaviors>
          <behavior name="mex" >
            <serviceMetadata httpGetEnabled="true" />
          </behavior>
        </serviceBehaviors>
      </behaviors>
    </system.serviceModel>
    

Exemple

Le code d’exemple suivant indique comment utiliser une exigence de session au niveau du contrat et utiliser un fichier de configuration pour prendre en charge cette exigence avec la liaison System.ServiceModel.WSDualHttpBinding.

using System;
using System.Collections.Generic;
using System.ServiceModel;
using System.Threading;

namespace Microsoft.WCF.Documentation
{
  [ServiceContract(
    Name = "SampleDuplexHello",
    Namespace = "http://microsoft.wcf.documentation",
    CallbackContract = typeof(IHelloCallbackContract),
    SessionMode = SessionMode.Required
  )]
  public interface IDuplexHello
  {
    [OperationContract(IsOneWay = true)]
    void Hello(string greeting);
  }

  public interface IHelloCallbackContract
  {
    [OperationContract(IsOneWay = true)]
    void Reply(string responseToGreeting);
  }

  [ServiceBehaviorAttribute(InstanceContextMode=InstanceContextMode.PerSession)]
  public class DuplexHello : IDuplexHello
  {

    public DuplexHello()
    {
      Console.WriteLine("Service object created: " + this.GetHashCode().ToString());
    }

    ~DuplexHello()
    {
      Console.WriteLine("Service object destroyed: " + this.GetHashCode().ToString());
    }

    public void Hello(string greeting)
    {
      Console.WriteLine("Caller sent: " + greeting);
      Console.WriteLine("Session ID: " + OperationContext.Current.SessionId);
      Console.WriteLine("Waiting two seconds before returning call.");
      // Put a slight delay to demonstrate asynchronous behavior on client.
      Thread.Sleep(2000);
      IHelloCallbackContract callerProxy
        = OperationContext.Current.GetCallbackChannel<IHelloCallbackContract>();
      string response = "Service object " + this.GetHashCode().ToString() + " received: " + greeting;
      Console.WriteLine("Sending back: " + response);
      callerProxy.Reply(response);
    }
  }
}


Imports System.Collections.Generic
Imports System.ServiceModel
Imports System.Threading

Namespace Microsoft.WCF.Documentation
    <ServiceContract(Name:="SampleDuplexHello", Namespace:="http://microsoft.wcf.documentation", _
                     CallbackContract:=GetType(IHelloCallbackContract), SessionMode:=SessionMode.Required)> _
    Public Interface IDuplexHello
        <OperationContract(IsOneWay:=True)> _
        Sub Hello(ByVal greeting As String)
    End Interface

    Public Interface IHelloCallbackContract
        <OperationContract(IsOneWay:=True)> _
        Sub Reply(ByVal responseToGreeting As String)
    End Interface

    <ServiceBehaviorAttribute(InstanceContextMode:=InstanceContextMode.PerSession)> _
    Public Class DuplexHello
        Implements IDuplexHello

        Public Sub New()
            Console.WriteLine("Service object created: " & Me.GetHashCode().ToString())
        End Sub

        Protected Overrides Sub Finalize()
            Console.WriteLine("Service object destroyed: " & Me.GetHashCode().ToString())
        End Sub

        Public Sub Hello(ByVal greeting As String) Implements IDuplexHello.Hello
            Console.WriteLine("Caller sent: " & greeting)
            Console.WriteLine("Session ID: " & OperationContext.Current.SessionId)
            Console.WriteLine("Waiting two seconds before returning call.")
            ' Put a slight delay to demonstrate asynchronous behavior on client.
            Thread.Sleep(2000)
            Dim callerProxy As IHelloCallbackContract = OperationContext.Current.GetCallbackChannel(Of IHelloCallbackContract)()
            Dim response = "Service object " & Me.GetHashCode().ToString() & " received: " & greeting
            Console.WriteLine("Sending back: " & response)
            callerProxy.Reply(response)
        End Sub
    End Class
End Namespace
<appSettings>
  <!-- use appSetting to configure base address provided by host -->
  <add key="baseAddress" value="http://localhost:8080/ServiceMetadata" />
</appSettings>
<system.serviceModel>
  <services>
    <service 
      name="Microsoft.WCF.Documentation.DuplexHello"
      behaviorConfiguration="mex"
    >
      <endpoint
        address="/DuplexService"
        binding="wsDualHttpBinding"
        contract="Microsoft.WCF.Documentation.IDuplexHello"
       />
      <endpoint
        address=""
        binding="mexHttpBinding"
        contract="IMetadataExchange"
      />
    </service>
  </services>
  <behaviors>
    <serviceBehaviors>
      <behavior name="mex" >
        <serviceMetadata httpGetEnabled="true" />
      </behavior>
    </serviceBehaviors>
  </behaviors>
</system.serviceModel>

Voir aussi