Showing posts with label Fitnesse. Show all posts
Showing posts with label Fitnesse. Show all posts

Tuesday, December 4, 2012

Automated System Testing

As I described earlier we decided that we wanted to prioritize automation of our functional system testing. The trickiest thing for us was finding the right abstraction level for theses tests. In precious projects where we have been working with Fitnesse as a test tool we have failed to find a good abstraction level.

We have always ended up with tests that are super technical in nature and cluttered with details that are very implementation specific. The problem this has given us is that very few people understand the test cases. Especially testers tend to have problems understanding them as they are so technical. If our testers can't work with our tests then we do have some sort of problem (quite a few and I will get to them later).

This time around we set out to increase the level of abstraction in the tests to make them more aimed towards testing requirements and less towards testing technology. We where hoping to achieve two thins, less maintainance and more readability. Maintainance budget for our automated tests had been high in the past. The technical tests exposed too much implementation and hence most refactoring resulted in test rewrite. This was shit because our tests didn't help to secure our refactoring. This was something we had to address as well.

The level we went for was something like this. (In pseudo fitnesse)

|Register user with first name|Joe|last name|Doe|and email|jd@test.mail.xx|
|verify registration email|

We abstracted out the interfaces from the test cases and just loosely verified that things went right.

This registration test could be testing registration through the web portal or directly on the REST Service. This did lower the maintenance drastically. It did give us room to refactor or application without affecting the test cases. Though we where still having trouble getting our testers to write test cases that worked and made seance. The example above is obviously simplified and out of context, our test cases where quite long and complex. The biggest problem was what fixture method to use and how to design new ones with right abstraction level.

This exposed the need for something we really hadn't thought much about before, test architecture. We where really (and still are) lacking a test architect. Defining abstraction layers, defining test components, reusability of testcomponents, handling of test data, ect. All these become dramatically wrong when done by testers alone and not good enough when done by developers either.

Another problem we ran into with this abstraction level was that our testers didn't know our interfaces. The test doesnt really care about the interface so the tester doesn't need to take responsibility for the REST interface. Imho the responsibility of securing the quality of a public REST interface should lay with the testers. But here we give them tools to only secure registration functionality. Yes they are verifying the requirement to be able to register but the verification of the REST interface is implicit and left to the fixture implementation. This is not good.

It also generated a huge problem for us. We had integration tests with our partners that consume our REST interfaces and our testers who where in the sessions dint know our interfaces. When should they have learned them this was the first time they where exposed to them. They also where required to use tooling that they dint use other wise to test, REST clients of what ever flavor.

We had solved one thing but created another problem.

Had we abstracted too much? Was this the wrong level to test on?

Before we analyzed this we started to compensate for these issues by just jamming in more validations.

!define METHOD {POST}
|Register user by sending a |REST_REQUEST|${METHOD}| with first name|Joe|last name|Doe|and email|jd@test.mail.xx|
|verify registration email|

Still a fictive example but Im trying to just illustrate how it went downhill. So we basically broke our intended abstraction layer and made our tests into shit. But it got worse. Our original intent was that registration is registration regardless of channel, web portal or rest. But then we had to have different templates for different users. Say that it was based on gender. So we took our web portal test case and made that register a female user and verify the template by string matching and then we used the REST interface for the guys.

Awesome now we made sure that we got a HTTP 200 on our REST response, we made sure that we used pink templates for the guys and green ones for the gals. Awesome and we made sure to test our web interface and our rest interface. Sweeet!!! We had covered everything!

Well maybe not.

This is when we started to think again and our conclusion was that the abstraction layer of the initial tests was actually quite ok.

|Register user with first name|Joe|last name|Doe|and email|jd@test.mail.xx|
|verify registration email|

This tests a requirement. Its a functional test. It does have a value. Leave it at that! But it cant be our only test case to handle registration.

Coming back to this picture 

Our most prioritized original need was to have regression test on functional system, end to end of our delivery. We had that. We also had unit tests on the important mechanisms of the system, not on everything but and yest too little but on the key parts. Still we where lacking something and that something was component/subsystem end to end tests. This was something we deep  down always knew that we would have to make but we had ignored it for quite some time due to "other prioritize". I still think we made the right call back then and there when we prioritized but this has been the most costly call of our entire journey.

So we started two tasks. One retro fitting Component Tests and cleaning up our System Tests. More on how that went and how we decided to abstract these in the next post.

Friday, November 23, 2012

What is Continuous Regression Testing?

In my previous entry I said that our business case was Continuous Regression Testing. I will make a few entries on the subject.

Our definition was quite clear on what level of testing we wanted to achieve.

We define it at the System Test level, meaning regression testing of our end to end functionality as specified by our Use Cases. Important here is end to end and driven by Use Cases.

As an example say that our system would have a "Register User" Use Case which states that the user should be able to register through a portal and receive an confirmation email. In this case our end to end delivery is from our web front to our mail server. We would be creating an automated Test Case which registers the users through the portal and then the test evaluates that there is a mail sent to the email address of the registered user.

Me and others in our company (not on the team at the time) at the time have had quite a bit of experience working with automated System Tests. Yet we ran into quite a few mines (AGAIN!!) when building our test suites. I will cover these later.

So we had a clear understanding on how we wanted to test and we knew we wanted to test it often. For us testing on each code commit and so heavily relying on test automation was way out of our comfort zone. But our business case was strong and we knew why we wanted to go down that road.

Early on we made a few key decisions. One was to test everything on every commit. Second was to only build each artifact once. We discussed this and came to the conclusion that we would need to retest after a rebuild. We felt our process would be simpler and more correct by doing this.

Our architecture was based on a few well defined components (publishing rest services) that together formed our deliverable.

This is a simplistic view of something similar. Some components where internal and some where externally integrating.

We where aware that we most likely would need to test the components in a continuous way but we ignored it on purpose. Our focus had to be on our delivery as well and we all know too well that we need to prioritize well when working on deadlines. Its easy to get carried away on theoretical models and a desire to solve everything but its not the way we work. We always want something deliverable and then iterate it.

So our initial pipe ended up looking something like this.  Each of our components where built, unit tested and released on commit. The our deployment assembly was updated one component at the time. Each time the assembly was updated we deployed it and tested it on our test server.

It was a very simplistic start to our Continuous journey but it was very adequate for us and most importantly it solved our primary concern Continuous Regression of the customer application.

Its important to remember that the application was new and our team was small at the time.