My Favorite SOA Patterns

A flexible service oriented architecture that handles multiple platforms (multiple devices, multiple databases…) | Posted on April 24, 2012 by Anuj Varma

The Problem Statement
Imagine that you have just built a sophisticated application to work against a SQL Server database. You followed a best-practices approach and separated out your presentation, business logic and data access layer. Your application is service oriented – … Continue reading →

Abstract Factory– Equally useful for manufacturing operations (services) and products | Posted on September 21, 2011 by Anuj Varma

This article assumes some familiarity with the Factory pattern. The factory concept is equally useful for creating products (ProductFactory) or for creating services (ServiceFactory). A good way to start is to look at what the client really needs from the … Continue reading →

WCF and Publish Subscribe–A Full Example: Running the Client (Subscriber) | Posted on July 28, 2011 by Anuj Varma

This entry is part 6 of 6 in the series WCF Publish Subscribe - A Full Example in C#, Step by Step

Now that all the pieces are in place, we are ready to run our client program. The first error I encountered was
AddressAccessDeniedException: HTTP could not register URL http://+:8080/

What I needed was to provide local access to the address on … Continue reading →

WCF and Publish Subscribe–A Full Example: Client Code | Posted on July 28, 2011 by Anuj Varma

This entry is part 5 of 6 in the series WCF Publish Subscribe - A Full Example in C#, Step by Step

The subscriber needs to know about the service. We will use svcutil.exe to generate the proxy class for the subscribers to use.
Step 1 : Ensure Service Loads Ok

Use CRL F5 to start the Magazine service – it should start running … Continue reading →

WCF and Publish Subscribe–A Full Example: The Event Generator | Posted on July 28, 2011 by Anuj Varma

This entry is part 4 of 6 in the series WCF Publish Subscribe - A Full Example in C#, Step by Step

The purpose of the Event Generator code is to publish events (New Magazine Issue Available) that subscribers will get notified about.

Add a new Console App (Add New Project) to the WCFPublishSubscribe solution. Call it EventGenerator.
Copy over the app.config and … Continue reading →

WCF Publish Subscribe– A Full Example: The Service Side Part 2 (Implementation) | Posted on July 28, 2011 by Anuj Varma

This entry is part 3 of 6 in the series WCF Publish Subscribe - A Full Example in C#, Step by Step

Our implementation is based on .NET events. The idea of publishing goes hand-in-hand with ‘raising an event’ – and the idea of subscribers goes hand-in-hand with consuming an event.
Our event based implementation thus consists of:

Defining an event
Defining an event … Continue reading →

WCF Publish Subscribe–A Full Example – The Service Side Part 1 (Interface) | Posted on July 28, 2011 by Anuj Varma

This entry is part 2 of 6 in the series WCF Publish Subscribe - A Full Example in C#, Step by Step

The Service code contains of an Interface and its implementation

The Interface defines all the capabilities of the service. What do we really want from a Publisher service?

A Publish method (called PublishMagazine)
A Subscribe method (to allow clients to subscribe to the … Continue reading →

WCF and Publish Subscribe– A Full Example: Introduction | Posted on July 28, 2011 by Anuj Varma

This entry is part 1 of 6 in the series WCF Publish Subscribe - A Full Example in C#, Step by Step

Imagine that you are a magazine publishing company. Your revenue depends on subcribers – in particular, happy subscribers. To ensure that your subscribers stay happy, one of the foremost services you need to provide is timely noticification whenever a new … Continue reading →