So - I decided a few days ago to sit down and spend a few evenings setting up a Continuous Integration environment which would
- A) Run clientside tests in a Continuous Integration server
- B) Provide TDD-stylish feedback on both NUnittests and clientside tests
Disclaimer: If you don't have experience with Continuous Integration environments you might find this to go a bit over your head - I strongly recommend this article written my Martin Fowler and if you really want to dig deep into the subject "Continuous Integration - Improving Software Quality and Reducing Risk" is a must-read.
How it was done
So - you write a test in a script and execute it in a browser and get a list of failing and completed tests. If everything is OK the top banner is green (left). If one or more tests fail the banner is red (right). This is controlled by CSS-class called "pass" and "fail". With that in mind and with a little knowledge of Watin I decided to just use write a unittest in Watin because it would allow me to write an test resembling the following:
public void ExerciseQUnitTests()
using (var ie = new IE("http://(website)/UITest/QUnitTests.aspx"))
Assert.AreEqual("pass", ie.Element("banner").ClassName, "QUnittest(s) have failed");
...where QUnitTests.aspx should be the page exercising my QUnit tests. The test itself should check for a specific class in the top banner - if "fail" would be active one or more tests would have failed and the unittest should fail and cause a red build. There is at least one obvious gotcha to this approach: You only get to know that one or more clientside-tests have failed. You don't get to know which one and why it failed. Not very TDD'yish but it'll do for now.
Here's a list of the things I needed to do once I had my Watin-test written:
- I created a new project on my private CruiseControl.NET server which would download the sourcecode from my VS project, compile it using MSBuild and execute the unittests in my testproject. I battled for an hour or so with Watin because it needs to have ApartementState explicitly set. You won't have any problem when running your test in Visual Studio only but whenever you try to run the Watin test outside Visual Studio you get - well, funny errors basicly.
- I pointed the the website to the build output folder in Internet Information Server
- Then I ran into another problem - QUnit appearenly didn't seem to work very well with Internet Explorer 7 (or so I thought) - the website simply didn't output any testresults on my build server. It wasn't a 404 error or so - the page was just plain blank - so I had working tests on my laptop and failing tests on my buildserver. Without thinking much about it I upgraded to Internet Explorer 8 on my buildserver. Not much of deal so I did it - just to find out that the webpage still didn't output any results in IE 8 either. After a while of "What the f*** is going on" I started thinking again and vaguely remembered a similar problem I had about halft a year ago... The problem back then was that scripting in IE7 is disabled per default on Windows 2008 - which of course was the problem here as well. So I enabled scripting and finally got my ExerciseQUnitTests test to pass. Guess what happened when I forced a rebuild: GREEN LIGHTS EVERYWHERE. Yeeeehaaaaaaaa :o)
- Last, but not least I found out that CruiseControl.NET from now on will have to run in Console-mode in order to interact with the desktop in a timely fashion - because it needs to fire up a web browser - oh dear... I need to look into that one because I define having console apps running in a server environment as heavy technical debt you need to work your way around somehow. But again: It'll do for now even though I find it a little akward.
CruiseControl.NET - an opensource Continuous Integration server for Windows
Watin - web test automating tool for .NET