My useless websites

We recently had a competition at work where you had to create a ‘useless website’. There weren’t many rules to the contest (make it publicly accessible, SSFW, enter as many times as you like), so I decided to hedge my bets and create/submit half a dozen simple sites all using the same concept of randomly generating something.

It was a good example of disposable software as I could churn out an entire site in 10 or 15 minutes including publishing it live on github and didn’t have to worry about tests/technical debt or any such thing. It was really fun.

I ended up with a runner’s up award for the sloth site, the winner was my very talented colleague James and his ‘Potato Simulator 2015‘.

Here’s the six sites I created in a week:

pizzagenerator
Pizza Generator: randomly generate a succulent pizza (with bonus exotic mode)
Drink Tea Every Day: Australian Tea Tally
Drink Tea Every Day: Australian Tea Tally
Are you faster than a sloth?
Are you faster than a sloth?
Quote of the Day
Quote of the Day
Are you taller than a giraffe?
Are you taller than a giraffe?
Ralph says...
Ralph says…

100,000 e2e selenium tests? Sounds like a nightmare!

This story begins with a promo email I received from Sauce Labs…

“Ever wondered how an Enterprise company like Salesforce runs their QA tests? Learn about Salesforce’s inventory of 100,000 Selenium tests, how they run them at scale, and how to architect your test harness for success”

saucelabs email

100,000 end-to-end selenium tests and success in the same sentence? WTF? Sounds like a nightmare to me!

I dug further and got burnt by the molten lava: the slides confirmed my nightmare was indeed real:

Salesforce Selenium Slide

“We test end to end on almost every action.”

Ouch! (and yes, that is an uncredited image from my blog used in the completely wrong context)

But it gets worse. Salesforce have 7500 unique end-to-end WebDriver tests which are run on 10 browsers (IE6, IE7, IE8, IE9, IE10, IE11, Chrome, Firefox, Safari & PhantomJS) on 50,000 client VMs that cost multiple millions of dollars, totaling 1 million browser tests executed per day (which equals 20 selenium tests per day, per machine, or over 1 hour to execute each test).

Salesforce UI Testing Portfolio

My head explodes! (and yes, another uncredited image from this blog used out of context and with my title removed).

But surely that’s only one place right? Not everyone does this?

A few weeks later I watched David Heinemeier Hansson say this:

“We recently had a really bad bug in Basecamp where we actually lost some data for real customers and it was incredibly well tested at the unit level, and all the tests passed, and we still lost data. How the f*#% did this happen? It happened because we were so focused on driving our design from the unit test level we didn’t have any system tests for this particular thing.
…And after that, we sort of thought, wait a minute, all these unit tests are just focusing on these core objects in the system, these individual unit pieces, it doesn’t say anything about whether the whole system works.”

~ David Heinemeier Hansson – Ruby on Rails creator

and read that he had written this:

“…layered on top is currently a set of controller tests, but I’d much rather replace those with even higher level system tests through Capybara or similar. I think that’s the direction we’re heading. Less emphasis on unit tests, because we’re no longer doing test-first as a design practice, and more emphasis on, yes, slow, system tests (Which btw do not need to be so slow any more, thanks to advances in parallelization and cloud runner infrastructure).”

~ David Heinemeier Hansson – Ruby on Rails creator

I started to get very worried. David is the creator of Ruby on Rails and very well respected within the ruby community (despite being known to be very provocative and anti-intellectual: the ‘Fox News’ of the ruby world).

But here is dhh telling us to replace lower level tests with higher level ‘system’ (end to end) tests that use something like Capybara to drive a browser because unit tests didn’t find a bug and because it’s now possible to parallelize these ‘slow’ tests? Seriously?

Speed has always seen as the Achille’s heel of end to end tests because everyone knows that fast feedback is good. But parallelization solves this right? We just need 50,000 VMs like Salesforce?

No.

Firstly, parallelization of end to end tests actually introduces its own problems, such as what to do with tests that you can’t run in parallel (for example, ones that change global state of a system such as a system message that appears to all users), and it definitely makes test data management trickier. You’ll be surprised the first time you run an existing suite of sequential e2e tests in parallel, as a lot will fail for unknown reasons.

Secondly, the test feedback to someone who’s made a change still isn’t fast enough to enable confidence in making a change (by the time your app has been deployed and the parallel end-to-end tests have run; the person who made the change has most likely moved onto something else).

But the real problem with end to end tests isn’t actually speed. The real problem with end to end tests is that when end to end tests fail, most of the time you have no idea what went wrong so you spend a lot of time trying to find out why. Was it the server? Was it the deployment? Was it the data? Was it the actual test? Maybe a browser update that broke Selenium? Was the test flaky (non-deterministic or non-hermetic)?

Rachel Laycock and Chirag Doshi from ThoughtWorks explain this really well in their recent post on broken UI tests:

“…unlike unit tests, the functional tests don’t tell you what is broken or where to locate the failure in the code base. They just tell you something is broken. That something could be the test, the browser, or a race condition. There is no way to tell because functional tests, by definition of being end-to-end, test everything.”

So what’s the answer? You have David’s FUD about unit testing not catching a major bug in BaseCamp. On the other hand you need to face the issue of having a large suite of end to end tests will most likely result in you spending all your time investigating test failures instead of delivering new features quickly.

If I had to choose just one, I would definitely choose a comprehensive suite of automated unit tests over a comprehensive suite of end-to-end/system tests any day of the week.

Why? Because it’s much easier to supplement comprehensive unit testing with human exploratory end-to-end system testing (and you should anyway!) than trying to manually verify units function from the higher system level, and it’s much easier to know why a unit test is broken as explained above. And it’s also much easier to add automated end-to-end tests later than trying to retrofit unit tests later (because your code probably won’t be testable and making it testable after-the-fact can introduce bugs).

To answer our question, let’s imagine for a minute that you were responsible for designing and building a new plane. You obviously need to test that your new plane works. You build a plane by creating parts (units), putting these together into components, and then putting all the components together to build the (hopefully) working plane (system).

If you only focused on unit tests, like David mentioned in his Basecamp example, you could be pretty confident that each piece of the plane would be have been tested well and works correctly, but wouldn’t be confident it would fly!

If you only focussed on end to end tests, you’d need to fly the plane to check the individual units and components actually work (which is expensive and slow), and even then, if/when it crashed, you’d need to examine the black-box to hopefully understand which unit or component didn’t work, as we currently do when end-to-end tests fail.

But, obviously we don’t need to choose just one. And that’s exactly what Airbus does when it’s designing and building the new Airbus A350:

As with any new plane, the early design phases were riddled with uncertainty. Would the materials be light enough and strong enough? Would the components perform as Airbus desired? Would parts fit together? Would it fly the way simulations predicted? To produce a working aircraft, Airbus had to systematically eliminate those risks using a process it calls a “testing pyramid.” The fat end of the pyramid represents the beginning, when everything is unknown. By testing materials, then components, then systems, then the aircraft as a whole, ever-greater levels of complexity can be tamed. “The idea is to answer the big questions early and the little questions later,” says Stefan Schaffrath, Airbus’s vice president for media relations.

The answer, which has been the answer all along, is to have a balanced set of automated tests across all levels, with a disciplined approach to having a larger number of smaller specific automated unit/component tests and a smaller number of larger general end-to-end automated tests to ensure all the units and components work together. (My diagram below with attribution)

Automated Testing Pyramid

Having just one level of tests, as shown by the stories above, doesn’t work (but if it did I would rather automated unit tests). Just like having a diet of just chocolate doesn’t work, nor does a diet that deprives you of anything sweet or enjoyable (but if I had to choose I would rather a diet of healthy food only than a diet of just chocolate).

Now if we could just convince Salesforce to be more like Airbus and not fly a complete plane (or 50,000 planes) to test everything every-time they make a change and stop David from continuing on his anti-unit pro-system testing anti-intellectual rampage which will result in more damage to our industry than it’s worth.

Waterfall, Agile Development & Hyperbole

Hyperbole. Love it or hate it, it’s been around for centuries and is here to stay. And, as someone pointed out this week, I’m guilty as charged of using (abusing?) it on this blog. You just need to quickly flick through my recent posts to find such melodramatic titles such as ‘Do you REALLY need to run your WebDriver tests in IE?‘, ‘UI automation of vendor delivered products always leads to trouble‘, and  ‘Five signs you’re not agile; you’re actually mini-waterfall‘. Hyperbole supports my motto for this blog and my life: strong opinions, weakly held.

But it’s not just me who likes hyperbole mixed into their blog posts. Only this morning did I read the catchy titled ‘Waterfall Is Never the Right Approach‘ followed quickly with a similarly catchy titled rebuttal: ‘Why waterfall kicks ass‘ (I personally would have capitalized ‘NEVER’ and ‘ASS’).

While I found both of articles interesting, I think they both missed the key difference between waterfall and agile software development (and why waterfall rarely works in these fickle times): waterfall is sequential whereas agile development is (at least meant to be) iterative.

I personally don’t care whether you do SCRUM or XP, whether you write your requirements in Word™ or on the back of an index card, or even if you stand around in a circle talking about what card you’re working on.

What I do care about is whether you’re delivering business value frequently and adjusting to the feedback you get.

Sequential ‘big bang’ development such as waterfall, by its nature, delivers business value less frequently, and chances are when that value is realized the original problem has changed (depending on how long ago that was), because as I stated and believe, we live in fickle times.

Iterative development addresses this by developing/releasing small fully functional pieces of business value iteratively and adjusting to feedback/circumstance.

Just because an organization practices what they call ‘agile’, doesn’t mean they’re delivering business value iteratively. I’ve seen plenty of ‘agile’ projects deliver business value very non-frequently, they’re putting a sequential process into agile ‘sprints’ followed by a large period of end to end, business and user acceptance testing, with a ‘big bang’ go live.

Whilst I believe iterative development is the best way to work; I’m not dogmatic (enough) to believe it’s the only way to work. Whilst I believe you could build and tests parts of say an aeroplane iteratively, I still hope there’s it’s a sequential process with a whole heap of testing at the end on a fully complete aeroplane before I take my next flight in it.

Five signs you’re not agile; you’re actually mini-waterfall

Update: I’ve added five remedies to make you less waterfall in a separate post

I’ve noticed a lot of projects call themselves agile when in fact they’re mini-waterfall, also known as scrumfall. Here’s five warning signs that you’ll see if you fall into that category:

  1. Development for your user stories seems to take almost all of the iteration and only move to ‘ready for test’ during the afternoon of the last day of your iteration
  2. You have a whole lot of user stories that are waiting business ‘signoff’ and can’t be worked on
  3. You have a large chunk of time set aside at the end of the project for ‘user acceptance testing’
  4. Team members live in fear of changing something or moving a story card around something as they’re scared of being ‘told off’
  5. You develop in iterations but only release everything big bang at the end when everything is considered ‘done’

Long live the analyst-programmer

“Getting things done means doing things you might not be interested in. No matter how sexy a project is, there are always boring tasks. Tedious tasks. Tasks that a less mature engineer may deem beneath their dignity or their job title.”

~ John Allspaw

Once upon a time, before we called ourselves agile, there lived a role called an analyst-programmer. The analyst-programmer was a generalist before generalists became cool: just as content to analyze a requirement as to write some code and implement it.

Along came agile software development and its disturbing trend towards having senior developers that are above anything but pure coding. Writing SQL scripts for reference data, analyzing what is actually required, configuring a CI build: these are all tedious tasks that take away from what the senior developer is supposedly entitled to do: just write code to meet explicit acceptance criteria. The senior developer expects a flock of paradevs to run around doing their analysis, writing their acceptance criteria, and finally testing the code that they write. Some even expect the paradev to read the acceptance criteria aloud to them, because reading themselves isn’t coding.

You’ll start to notice who these senior developers are when you hear them say things like “I get paid too much to do this”, or “why are you wasting my time having me do this?”.

One day I imagine a world where all software development roles are suitably generalist and humble, that instead of complaining that “I’m too good for this”, people in these roles simply get their hands dirty and get things done.