Monthly Archives: March 2013

Rolling rolling rolling – rolling back your data back in integration tests

C#, NUnit, Refactoring, unit testing,

A couple years ago, I had just started refactoring a legacy codebase by adding integration tests and was manually rolling back the database changes with several lines of handwritten sql deletes… (sorry). At Iowa Code Camp, I went to a Lee Brandt demo and looking at Lee’s demo code, I saw him using a transaction for the rollbacks and I hung my head in shame.

Try it like this:

using NUnit.Framework;
using System.Transactions;
namespace ProjectName.Tests.Integration
{
 [TestFixture]
 public class TestClass
 {
 private TransactionScope _transactionScope;
 [SetUp]
 public void SetUp()
 {
 _transactionScope = new TransactionScope(TransactionScopeOption.RequiresNew);
 }
 //...Test some stuff, insert records, update records, etc...
 [TearDown]
 public void TearDown()
 {
 _transactionScope.Dispose();
 }
 }
}

Happy Testing,

Jim

Tips and Tricks: Start Windows service in a console window

C#, Windows Services

I spend a lot of time writing windows services. If I had to install every one I worked on locally, my box would be terribly tired and a mess to boot.

Here is a way to  start a service in a console window without installing it on your box. Use this code in your Main. You will have to add the string[] args parameter if you do not have it.


static void Main(string[] args)
{
     //Start IOC Container Structuremap
     //http://structuremap.net/structuremap/
     _bootStrapper = new IocContainerBootstrapper();
     _bootStrapper.BootstrapStructureMap();

     //This configurator starts up log4net
     XmlConfigurator.Configure();

     Log.DebugFormat("The SweetService service bootstrapped '{0}':", ObjectFactory.WhatDoIHave());

     //Add '/console' to start options > Command Line Arguments in
     //your project properties
     //to get the service to start in console for debugging
     if (args.Length > 0 && args[0] == "/console")
     {
          Log.Debug("Starting this sweet service in Console mode for debugging");
          SweetService myService = new SweetService();
          myService.OnStart(args);
          Console.ReadKey();
     }
     else
     {
          ServiceBase[] servicesToRun = new ServiceBase[]
          { new SweetService() };
          Run(servicesToRun);
     }
}

Put  ‘console’ in your Start Options / Command line arguments in your visual studio project properties and set your project type to Console Application.

When you start the project now in a debugger, you will get a lovely console window with all your log4net output and you never had to install the service to work on it.

For this example, I am using log4net and I am using a colored console appender.  That makes the output in the console window great.

Enjoy,

Jim

My way or the highway! Activator.CreateInstance

C#

I have an object that I always need created in one specific way. Its bits have to be loaded in a certain order and I want to control whenever that happens. Any other code requiring this object has to call my loader method.

I implement like this, using Activator.CreateInstance:

  1. Give the object a private constructor.
public class Monkey
{
     private Monkey()
     {}
}

2. In my loader class, I use Activator.CreateInstance like this:

(Monkey)Activator.CreateInstance(typeof(Monkey), true);

I also use this same activator code to spin up one of these monkeys in my test classes.

Entity Framework Validation Errors

C#, Entity Framework

Found this lovely little code snipped for interrogating the database validation errors sent back from an Entity Framework Save:


catch (DbEntityValidationException e)
{
foreach (var eve in e.EntityValidationErrors)
{
Console.WriteLine("Entity of type \"{0}\" in state \"{1}\" has the following validation errors:",
eve.Entry.Entity.GetType().Name, eve.Entry.State);
foreach (var ve in eve.ValidationErrors)
{
Console.WriteLine("- Property: \"{0}\", Error: \"{1}\"",
ve.PropertyName, ve.ErrorMessage);
}
}
throw;

Enjoy,

-Jim

Test base class thanks to Rob Connery

C#, Uncategorized, unit testing, , ,

I saw this great testbase class in a Tekpub video. Thank goodness for tekpub videos. I wish everything that I purchased was that pragmatic.

public class TestBase
{
	public static string GetCaller()
	{
		StackTrace stackTrace = new StackTrace();
		return stackTrace.GetFrame(2).GetMethod().Name;
	}

	public void IsPending()
	{
		Console.WriteLine("{0} -- pending", GetCaller());
	}

	public void Describes(string description)
	{
		Console.WriteLine("-----------------------");
		Console.WriteLine(description);
		Console.WriteLine("-----------------------");
	}
}