Remember to download the samples from the GitHub repository.

Running

When using Visual Studio 2017 the NuGet packages should be restored automatically. If you find that they do not or if you are using an older version of Visual Studio please execute the following in a Visual Studio command prompt:

cd {extraction-folder}\Shuttle.Esb.Samples\Shuttle.RequestResponse
nuget restore

Once you have opened the Shuttle.RequestResponse.sln solution in Visual Studio set the following projects as startup projects:

  • Shuttle.RequestResponse.Client
  • Shuttle.RequestResponse.Server

Implementation

In order to get any processing done in Shuttle.Esb a message will need to be generated and sent to an endpoint for processing. The idea behind a command message is that there is exactly one endpoint handling the message. Since it is an instruction the message absolutely has to be handled and we also need to have only a single endpoint process the message to ensure a consistent result.

In this guide we’ll create the following projects:

  • a Console Application called Shuttle.RequestResponse.Client
  • a Console Application called Shuttle.RequestResponse.Server
  • a Class Library called Shuttle.RequestResponse.Messages that will contain all our message classes

Messages

Create a new class library called Shuttle.RequestResponse.Messages with a solution called Shuttle.RequestResponse

Note: remember to change the Solution name.

RegisterMemberCommand

Rename the Class1 default file to RegisterMemberCommand and add a UserName property.

namespace Shuttle.RequestResponse.Messages
{
	public class RegisterMemberCommand
	{
		public string UserName { get; set; }
	}
}

MemberRegisteredEvent

Add a new class called MemberRegisteredEvent also with a UserName property.

namespace Shuttle.RequestResponse.Messages
{
	public class MemberRegisteredEvent
	{
		public string UserName { get; set; }
	}
}

Client

Add a new Console Application to the solution called Shuttle.RequestResponse.Client.

Install the Shuttle.Esb.Msmq nuget package.

This will provide access to the Msmq IQueue implementation and also include the required dependencies.

Install the Shuttle.Core.Castle nuget package.

This will provide access to the Castle WindsorContainer implementation.

Add a reference to the Shuttle.RequestResponse.Messages project.

Program

Implement the main client code as follows:

using System;
using Castle.Windsor;
using Shuttle.Core.Castle;
using Shuttle.Esb;
using Shuttle.RequestResponse.Messages;

namespace Shuttle.RequestResponse.Client
{
	internal class Program
	{
		private static void Main(string[] args)
		{
			var container = new WindsorComponentContainer(new WindsorContainer());

			ServiceBus.Register(container);

			using (var bus = ServiceBus.Create(container).Start())
			{
				string userName;

				while (!string.IsNullOrEmpty(userName = Console.ReadLine()))
				{
					bus.Send(new RegisterMemberCommand
					{
						UserName = userName
					}, c => c.WillExpire(DateTime.Now.AddSeconds(5)));
				}
			}
		}
	}
}

App.config

Create the shuttle configuration as follows:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
	<configSections>
		<section name='serviceBus' type="Shuttle.Esb.ServiceBusSection, Shuttle.Esb"/>
	</configSections>

	<serviceBus>
		<messageRoutes>
			<messageRoute uri="msmq://./shuttle-server-work">
				<add specification="StartsWith" value="Shuttle.RequestResponse.Messages" />
			</messageRoute>
		</messageRoutes>		

		<inbox
		   workQueueUri="msmq://./shuttle-client-work"
		   errorQueueUri="msmq://./shuttle-error" />
	</serviceBus>
</configuration>

This tells Shuttle that all messages that are sent and have a type name starting with Shuttle.RequestResponse.Messages should be sent to endpoint msmq://./shuttle-server-work.

MemberRegisteredHandler

Create a new class called MemberRegisteredHandler that implements the IMessageHandler<MemberRegisteredEvent> interface as follows:

using System;
using Shuttle.Esb;
using Shuttle.RequestResponse.Messages;

namespace Shuttle.RequestResponse.Client
{
	public class MemberRegisteredHandler : IMessageHandler<MemberRegisteredEvent>
	{
		public void ProcessMessage(IHandlerContext<MemberRegisteredEvent> context)
		{
			Console.WriteLine();
			Console.WriteLine("[RESPONSE RECEIVED] : user name = '{0}'", context.Message.UserName);
			Console.WriteLine();
		}
	}
}

Server

Add a new Console Application to the solution called Shuttle.RequestResponse.Server.

Install the Shuttle.Esb.Msmq nuget package.

This will provide access to the Msmq IQueue implementation and also include the required dependencies.

Install the Shuttle.Core.ServiceHost nuget package.

The default mechanism used to host an endpoint is by using a Windows service. However, by using the Shuttle.Core.ServiceHost we are able to run the endpoint as a console application or register it as a Windows service for deployment.

Install the Shuttle.Core.Castle nuget package.

This will provide access to the Castle WindsorContainer implementation.

Install the Shuttle.Core.Log4Net nuget package.

This will provide access to the Log4Net implementation.

Add a reference to the Shuttle.RequestResponse.Messages project.

Host

Implement the Program class as follows:

using Shuttle.Core.ServiceHost;

namespace Shuttle.RequestResponse.Server
{
    internal class Program
    {
        private static void Main()
        {
            ServiceHost.Run<Host>();
        }
    }
}

This will simply instance the Host class and get it running.

Add a Host class and implement the IServiceHost and IDisposabe interfaces as follows:

using Castle.Windsor;
using log4net;
using Shuttle.Core.Castle;
using Shuttle.Core.Log4Net;
using Shuttle.Core.Logging;
using Shuttle.Core.ServiceHost;
using Shuttle.Esb;

namespace Shuttle.RequestResponse.Server
{
    public class Host : IServiceHost
    {
        private IServiceBus _bus;

        public Host()
        {
            Log.Assign(new Log4NetLog(LogManager.GetLogger(typeof(Host))));
        }

        public void Start()
        {
            var container = new WindsorComponentContainer(new WindsorContainer());

            ServiceBus.Register(container);

            _bus = ServiceBus.Create(container).Start();
        }

        public void Stop()
        {
            _bus.Dispose();
        }
    }
}

App.config

Add an Application Configuration File item to create the App.config and populate as follows:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
	<configSections>
		<section name='serviceBus' type="Shuttle.Esb.ServiceBusSection, Shuttle.Esb"/>
	</configSections>

	<serviceBus>
		 <inbox
			workQueueUri="msmq://./shuttle-server-work"
			errorQueueUri="msmq://./shuttle-error" />
	</serviceBus>
</configuration>

RegisterMemberHandler

Add a new class called RegisterMemberHandler that implements the IMessageHandler<RegisterMemberCommand> interface as follows:

using System;
using Shuttle.Esb;
using Shuttle.RequestResponse.Messages;

namespace Shuttle.RequestResponse.Server
{
	public class RegisterMemberHandler : IMessageHandler<RegisterMemberCommand>
	{
		public void ProcessMessage(IHandlerContext<RegisterMemberCommand> context)
		{
			Console.WriteLine();
			Console.WriteLine("[MEMBER REGISTERED] : user name = '{0}'", context.Message.UserName);
			Console.WriteLine();

			context.Send(new MemberRegisteredEvent
			{
				UserName = context.Message.UserName
			}, c => c.Reply());
		}
	}
}

Run

Set both the client and server projects as startup projects.

Execute

Execute the application.

The client application will wait for you to input a user name. For this example enter my user name and press enter:

You will observe that the server application has processed the message.
The client application will then process the response returned by the server.

You have now completed a full request / response call chain.