How To – Host WCF in a Windows Service Using TCP

- J.D. Meier, Carlos Farre, Jason Taylor, Prashant Bansode, Steve Gregersen, Madhu Sundararajan, Rob Boucher

Applies To

  • Microsoft® Windows Communication Foundation (WCF) 3.5
  • Microsoft Visual Studio® 2008

Summary

This How To article walks you through the process of hosting a WCF service within a Microsoft Windows® service.

Contents

  • Objectives
  • Summary of Steps
  • Step 1 - Create a WCF Service
  • Step 2 - Configure the WCF Endpoints to Use TCP and Set the Base Address
  • Step 3 - Create a Windows Service
  • Step 4 - Add the Service Installers to the Windows Service
  • Step 5 - Modify the Windows Service to Host the WCF Service
  • Step 6 – Install the Windows Service
  • Step 7 – Create a Windows Forms Test Client Application
  • Step 8 - Add a WCF Service Reference to the Client
  • Step 9 – Test the Client and WCF Service
  • Additional Resources
  • Contributors and Reviewers

Objectives

  • Create a simple WCF service.
  • Host your WCF service in a Windows service using Transmission Control Protocol (TCP).
  • Create a simple client to consume your service.

Overview

WCF services can be self-hosted in an application (such as a console or a Windows Forms application), in a Windows service, in Internet Information Services (IIS) 6.0, or in IIS 7.0 with Windows Activation Services (WAS).

The advantages of hosting in a Windows service are:
  • Start on boot. The service will automatically be started when the hosting computer is rebooted.
  • Recovery. The service will be restarted by the Windows Service Control Manager if there is a failure.
  • Administration. Administrators already know how to manage Windows services.
  • Security Identity. Windows Service Control Manager allows you to choose an identity under which the process will run.
  • Binding flexibility. Hosting in a Windows service allows you to choose any binding protocol. IIS 6.0 only allows HTTP bindings.

The disadvantages of hosting in a Windows service are:
  • Installation. You must use a custom installer action or the .NET utility Installutil.exe.
  • Lack of enterprise features. Windows services do not have the security, manageability, scalability, and administrative features that are included in IIS.

To host WCF in a Windows service, you need to create the WCF service, create a Windows service to host the WCF service, and then install and run the Windows service. For the purposes of this How To article, you will use installutil.exe on the command line to install the service. In a production environment, you can use a setup program to install the service.

Summary of Steps

  • Step 1 - Create a WCF Service
  • Step 2 - Configure the WCF Endpoints to Use TCP and Set the Base Address
  • Step 3 - Create a Windows Service
  • Step 4 - Add the Service Installers to the Windows Service
  • Step 5 - Modify the Windows Service to Host the WCF Service
  • Step 6 – Install the Windows Service
  • Step 7 – Create a Windows Forms Test Client Application
  • Step 8 - Add a WCF Service Reference to the Client
  • Step 9 – Test the Client and WCF Service

Step 1 – Create a WCF service

In this step, you create a WCF service to test hosting in a Windows service.
  1. In Visual Studio, click File, click New, and then click Project.
  2. In the Add New Project dialog box, in the Templates section, select WCF Service Library.
  3. In the Add New Project dialog box, click OK to create the WCF Service Library project WcfServiceLibrary1.

Step 2 – Configure the WCF Endpoints to Use TCP and Set the Base Address

In this step, you modify the WCF configuration so that the endpoints use TCP instead of the default Hypertext Transfer Protocol (HTTP). You then set the base address for your service. Finally, you set HttpGetEnabled to false, since you will be running under TCP.
  1. Right-click the App.config file of the WCF Service Library project and then click Edit WCF Configuration. If you do not see the Edit WCF Configuration option, on the Tools menu, click WCF Service Configuration Editor. Close the WCF Service Configuration Editor tool that appears. The option should now appear on the App.config context menu.
  2. In the Configuration Editor, in the configuration section, expand Services and then expand Endpoints.
  3. Select the first endpoint. Under Endpoint Properties, change the Binding from wsHttpBinding to netTcpBinding.
  4. Select the second endpoint. Under Endpoint Properties, change the Binding from mexHttpBinding to mexTcpBinding.
  5. Under Service, select the Host node, select the default address under the BaseAddress list, and then click Edit.
  6. Set the base address to the following and then click OK:

net.tcp://localhost:8523/Service1
  1. Under Advanced, expand the tree under Service Behaviors. Select serviceMetadata and change HttpGetEnabled from True to False.
  2. Click File and then click Save to save your configuration changes.
  3. In Visual Studio, verify your configuration, which should look as follows:
  <system.serviceModel>
    <services>
      <service behaviorConfiguration="WcfServiceLibrary1.Service1Behavior"
        name="WcfServiceLibrary1.Service1">
        <endpoint address="" binding="*netTcpBinding*" bindingConfiguration=""
          contract="WcfServiceLibrary1.IService1">
          <identity>
            <dns value="localhost" />
          </identity>
        </endpoint>
        <endpoint address="mex" binding="*mexTcpBinding*" bindingConfiguration=""
          contract="IMetadataExchange" />
        <host>
          <baseAddresses>
            <add *baseAddress="net.tcp://localhost:8523/Service1"* />
          </baseAddresses>
        </host>
      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <behavior name="WcfServiceLibrary1.Service1Behavior">
          <serviceMetadata *httpGetEnabled="false*" />
          <serviceDebug includeExceptionDetailInFaults="false" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
  </system.serviceModel>

Note:
  • The port 8523 and Service1 are arbitrary for this example. If you run into a conflict where the port is in use, change it.
  • If you do not set HttpGetEnabled to False, you will get an exception in the Event Log when the service tries to start.

Step 3 – Create a Windows Service

In this step, you add a Windows Service project to your solution.
  1. Right-click your solution, cllick Add, and then click New Project.
  2. In the Add New Project dialog box, select Windows, and then select Windows Service.
  3. In the Name field, leave the default name WindowsService1 and then click OK to create a Windows service application.
  4. Copy App.config from your WCF Service Library project to your Windows service project. In the WCF Service Library project, right-click the App.config file, click Copy, and then right-click your Windows service project and click Paste.

Step 4 – Add the Service Installers to the Windows Service

In this step, you add service installers to your Windows service.
  1. Right-click Service1.cs and then click View Designer.
  2. Right-click the designer view and then click Add Installer. This adds the ProjectInstaller.cs file with two objects, serviceProcessInstaller1 and serviceInstaller1.
  3. In the Design view of ProjectInstaller.cs, right-click serviceProcessInstaller1 and then click Properties.
  4. In the Properties pane, set the Account attribute to NetworkService.
  5. Right-click serviceInstaller1 and then click Properties.
  6. In the Properties pane, set the StartType attribute to Automatic.

Step 5 – Modify the Windows Service to Host the WCF Service

In this step, you override the OnStart() and OnStop() methods to start and stop the WCF service inside the Windows service process.
  1. Add a reference to System.ServiceModel to your Windows Service project. To do so, in your Windows service project, right-click the References node and then click Add References. In the Add Reference dialog box, select System.ServiceModel and then click OK.
  2. Add a reference to your WCF Service Library project from your Windows service. To do so, in your Windows service project, right-click the References node and then click Add References. In the Add Reference dialog box, select the Projects tab. Select the WCF Service Library project, WcfServiceLibrary1, and then click OK.
  3. Add the following using statements to the Service1.cs file in your Windows service project.
using System.ServiceModel;
using WcfServiceLibrary1;
  1. Select Service1.cs and switch to code view.
  2. Declare an internal static member of ServiceHost type, as follows:

internal static ServiceHost myServiceHost = null;
  1. Override the OnStart method of the Windows service, to open the service host as follows:
protected override void OnStart(string[] args)
{
   if (myServiceHost != null)
   {
       myServiceHost.Close();
   }
   myServiceHost = new ServiceHost(typeof(Service1));
   myServiceHost.Open();
}
  1. Override the OnStop method of the Windows service, to close the service host as follows:
protected override void OnStop()
{
   if (myServiceHost != null)
   {
      myServiceHost.Close();
      myServiceHost = null;
   }
}
  1. Verify that your Service1.cs resembles the following:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.ServiceModel;
using WcfServiceLibrary1;

namespace WindowsService1
{
    public partial class Service1: ServiceBase
    {
        internal static ServiceHost myServiceHost = null; 

        public WCFServiceHost1()
        {
            InitializeComponent();
        }
        protected override void OnStart(string[] args)
        {
            if (myServiceHost != null)
            {
                myServiceHost.Close();
            }
            myServiceHost = new ServiceHost(typeof(Service1));
            myServiceHost.Open();
        }
        protected override void OnStop()
        {
            if (myServiceHost != null)
            {
                myServiceHost.Close();
                myServiceHost = null;
            }
        }
    }
}
  1. In the Solution Explorer, copy the App.config file from the WCF service project to the Windows service project so that the config file will be in both service binary folders after compiling.
  2. Build your solution and verify that your project produces WindowsService1.exe in your project \bin\debug directory of your WindowsService1 project.

Step 6 – Install the Windows Service

In this step, you install the Windows service and run it from the Services console.
  1. Rebuild the solution and open a Visual Studio command prompt.
  2. Browse to the bin directory of the project where WindowsService1.exe is located.
  3. Run the following command to install the service:

Installutil WindowsService1.exe
  1. Start your service. To do so, click Start, click Run, type services.msc and then click OK. Right-click your service and then click Start.

Note: If you have modified the service that is already installed, you can uninstall it by using following command:

Installutil /u WindowsService1.exe

Step 7 – Create a Windows Forms Test Client Application

In this step, you create a Windows Forms application named Test Client that you will use** to test the WCF service.
  1. Right-click your solution, click Add, and then click New Project.
  2. In the Add New Project dialog box, in the Templates section, select Windows Application.
  3. In the Name field, type Test Client and then click OK to create a Windows Forms application.

Step 8 – Add a WCF Service Reference to the Client

In this step, you add a reference from your test client to your WCF service
  1. Right-click your Test client project and select Add Service Reference.
  2. In the Add Service Reference dialog box, set the Address to the following and then click OK

net.tcp://localhost:8523/Service1

Note: net.tcp://localhost:8523/Service1 is the base address that you set in Step 3 above.

Step 9 – Test the Client and WCF Service

In this step, you use the test client to ensure that the WCF service is running properly.
  1. In your Client project, drag a button control onto your form.
  2. Double-click the button control to show the underlying code.
  3. In the code behind the button click, create an instance of the proxy, and call GetData of your WCF service. When you call the service, your current user security context will automatically be passed to your WCF Service. The code should look as follows:
        private void button1_Click(object sender, EventArgs e)
        {
            ServiceReference1.Service1Client myService = new ServiceReference1.Service1Client();
            MessageBox.Show(myService.GetData(123), “My Service”);
            myService.Close();
        }
  1. Right-click your client project and then click Set as Startup Project.
  2. Run the client application by pressing F5 or Ctrl+F5.
When you click the button on the form, the message “You entered: 123” should appear.

Additional Resources

Last edited Jun 11, 2008 at 10:40 PM by prashantbansode, version 1

Comments

mabra Mar 11, 2013 at 11:21 PM 
Hi !

Is at not simple ?? A simple example should and could have a simple download :-(

++mabra

codekitty Mar 4, 2009 at 7:02 PM 
Hi and thanks for the tutorial. i tried following the steps and must have missed something. When i tried to start the windows service in services.msc, it says "The Service1 service on local computer started and then stopped. Some services stop automatically if they have no work to do, for example, the Performance Logs and Alerts service." What did i miss? Thanks!!