Great article on the principles of K-I-S-S. Keep it simple, stupid!!

As an architect, I’ve learned a lot by doing things the hard way. It’s within our nature to be a purist. We love to dot our I’s and cross our T’s. We try to build the pie in the sky “This system is scalable, I can build anything on it!” Is that ever true. I doubt it.

If you are working on a new project, KISS is the way to go. Keep it simple, quick to market, and release often. We try to build systems and guess what we need, but in reality we don’t know, and building a large system for a unknown audience/market, is a big bet. A bet companies are not willing to pay.

Keep It Simple, Stupid

1. How do I know when new services are available, or how do I inform others of my new services?
2. How do I share object types across shared services?

Problem

To put some context around these two main questions.  Traditionally services are discovered by either searching the source tree or by word of month.  Neither of which is a great solution.  Services are either lost in thousands of lines of code, or lost in communication.

As for sharing object types across services.  By design services are usually developed with in its own domain and shouldn’t share types. But!, in some cases, you might actually have a business need to share certain types.  For instance, if you had two services within the same assembly that referenced a single object, when you created two different service references to the services, two objects will be defined under two different namespaces.

Solution

Disco files were created to answer these two very obvious questions.  With a disco file, developers can maintain a global list of available services.  Every time a new service is created, add the new WSDL URL to the list of services.  This list is the single point of reference when creating a Web or Service Reference.  Also, since there is only one global reference to all the services, the generated code will generate one namespace and recognized that if there are any shared types across services, it will only generate the type once.

Create the disco file number the vroot of your application. Below is an example disco file.

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<?xml version="1.0" encoding="utf-8" ?> 
<discovery xmlns="http://schemas.xmlsoap.org/disco/">
  <contractRef ref="http://localhost/ServiceA.svc?wsdl" docRef="ServiceA.svc" xmlns="http://schemas.xmlsoap.org/disco/scl/" />
  <contractRef ref="http://localhost/ServiceB.svc?wsdl" docRef="ServiceB.svc" xmlns="http://schemas.xmlsoap.org/disco/scl/" />
</discovery>

Consuming the disco file is no different:

In this example, I’ll show you how to use Extension methods to transform one object to another.  This is a great way to centralize your transformation code.

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
namespace ExtensionTest
{
    class Program
    {
        static void Main(string[] args)
        {
            Butterfly butterfly = new Caterpillar().ToButterfly();
        }
    }
 
    public static class Extensions
    {
        public static Butterfly ToButterfly(this Caterpillar caterpillar)
        {
            return new Butterfly() { Name = caterpillar.Name };
        }
    }
 
    public class Caterpillar
    {
        public string Name { get; set; }
    }
 
    public class Butterfly
    {
        public string Name { get; set; }
    }
}

Being the bad developer, I didn’t snapshot my image,  so now I’m going through the process of creating a new image.  And as I’m going through this process, I’m starting to realize I’m installing less and less on my dev machines.

So here is a list of software I needed:

• Visual Studio 2008 SP1
• Microsoft SQL Server 2008
• Microsoft Office 2007
• IIS7

That’s all I need on a daily basis.  The install has a small footprint and runs a lot quicker.  I’m starting to believe, setting up multiple VM with only the minimum required software on each machine is the way to go.  This allows me to turn on an off VM’s as I need them.  The machine can allocate 100% of its dedicated resource when it’s on and free it up once its off.

CodePlex Project: http://nerddinner.codeplex.com

Scott Hanselman - Mix09 NerdDinner.com

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protected void Application_BeginRequest(object sender, EventArgs e)
{
    Response.Clear();
    Response.Status = "301 Moved Permanently";
    Response.AddHeader("Location", "http://blog.wadolabs.com");
    Response.End();
}

This redirects your site via a 301 HTTP response code to the your new site.  In my case http://blog.wadolabs.com .  This keeps all my current links active and avoided a big fat 404 error.  You can do more sophisticated logic here and check the requested page and map the request to the new location, but for me, I was okay just doing a global redirect to the root of my new domain.

Download the installer here:

http://www.microsoft.com/downloads/details.aspx?FamilyID=53289097-73ce-43bf-b6a6-35e00103cb4b&displaylang=en

Get the lastest installers here:

http://silverlight.net/getstarted/silverlight3/default.aspx