SOA With NServiceBus

Sean Farmar

What is the problem we are trying to

solve?

•Scale

•Growth

•Stability and Durability

Why SOA?

•SOA's tenets are about reducing coupling.

•Coupling:

•Afferent, efferent

•Temporal

•Spatial

•Platform

Why SOA? [cont.]

n-tier architecture

In practice

In practice

•Domain decomposition

•Definition of components boundaries

•Using messaging and pub/sub

Publish Subscribe [pub/sub]

Publish Subscribe [pub/sub]

In practice [cont.]

•Following principles (best thinking):

•Explicit intentions [naming, context]

•Single Responsibility

•Command Query Separation

•Drive your design and decision making to address all aspects of coupling

•Backwards compatibility

Why NServiceBus?

•.Net Solution

•Distributed bus (not a broker)

•Messaging pub/sub (asynchronous)

•Durable and Transactional (if you want)

•Sagas

Why NServiceBus? [cont.]

•A Message

[Serializable]public class EventMessage : IMyEvent{

public Guid EventId { get; set; }public DateTime? Time { get; set; }

}

public interface IMyEvent{

Guid EventId { get; set; }DateTime? Time { get; set; }TimeSpan Duration { get; set; }

}

var m = new EventMessage();// Or:var m = Bus.CreateInstance<IMyEvent>();

Why NServiceBus? [cont.]

•Handlerpublic IBus Bus { get; set; }

public class EventMessageHandler : IHandleMessages<EventMessage>{

public void Handle(EventMessage message){

// do stuff...IMyEvent anotherEventMessage;

anotherEventMessage = Bus.CreateInstance<IMyEvent>();

anotherEventMessage = Guid.NewGuid();

anotherEventMessage = DateTime.Now.Second;

anotherEventMessage = TimeSpan.FromSeconds(99999D);

Bus.Publish(anotherEventMessage);}

}

Service Examples

Subscribe to Customer Status Updated

Publish

Customer Status Updated

Save status locally

Subscribe to Product Product Pricing UpdatedPricing Updated

Publish

Product Pricing Updated

Save pricing locally

Place Order

Publish Order Accepted

Sales

Marketing

Customer Care

Why NServiceBus? [cont.]

•Config

<?xml version="1.0"?><configuration>  <configSections>    <section name="UnicastBusConfig" type="NServiceBus.Config.UnicastBusConfig, NServiceBus.Core"/>    <section name="MessageForwardingInCaseOfFaultConfig" type="NServiceBus.Config.MessageForwardingInCaseOfFaultConfig, NServiceBus.Core" />  </configSections>

  <MessageForwardingInCaseOfFaultConfig ErrorQueue="error"/>

  <UnicastBusConfig ForwardReceivedMessagesTo="audit">    <MessageEndpointMappings>      <add Messages="MyMessages" Endpoint="MyServer"/>    </MessageEndpointMappings>  </UnicastBusConfig>  </configuration>

Why NServiceBus? [cont.]

•Integration

•Scalable

•Elegant programming model

•Developer productivity

•Used in the industry

A story about performance

A story about performance

•The evolution

A story about performance

•Turning the lights on

A story about performance

•Performance and Load testing

•Fixing it

•How did NServiceBus make it better?

Summary

•SOA

•NServiceBus

•You can do it

Q&A

Thank You!

nservicebus.comudidahan.com/blogSean Farmartwitter: @farmar