Automating Cucumber test scripts on a Mac

I’m really enjoying my work at the BBC on the Olympics team! I’m primarily implementing Cucumber scenarios to verify the work that the developers are doing. I’m also using other tools for stress testing and performance monitoring.

My work here is leading me to use Cucumber in weird and wonderful ways! Here’s an example. Yesterday i was asked to run a script every half an hour that tests the Olympics video player to see if it’s playing successfully, and if not, to email people to say that it’s broken. Not your usual Cucumber scenario, but amazingly enough, it can be used to do that!

Forgive the jargon below. PID is a programme identifier, and IVP is the Interactive Video Player that we are building.

  Scenario: Check LIVE video player
    Given a live PID 
    When I check the IVP 
    Then I should email people if anything goes wrong

I can use a combination of javascript hooks and taking screenshots a few seconds apart and comparing them to tell whether the video is running. I decided to run some step definitions that i’ve already defined and rescue any errors to be emailed. There are a few more steps in here but i’ve stripped it down a bit for simplicity.

When /^I check the IVP$/ do                                                                         
  if @pid
    begin
      step 'I attempt to view the IVP host page with that PID'
      step 'the video should be ready'
      step 'the video should be playing'
    rescue Exception => e
      @error = e.message
    end
  end
end

Notice that there might not actually be a live PID at the moment. It feels very weird, to put conditional logic in Cucumber step definitions like this!

Now comes the email part. I used Pony and sendmail as a simple email sending mechanism.

Then /^I should email people if anything goes wrong$/ do
  if @pid && @error
    subject = "Assurance test failed in #{ENV['ENVIRONMENT']}!"
    body = "#{page.current_url} caused this error: #{@error}"
    recipients = ['send_to@me.co.uk']

    Pony.mail(:to => recipients,
              :subject => subject,
              :body => body,
              :via => :sendmail)
  end
end

So, with that working, i set about putting it on a schedule. I thought i could just call the script from a cron task, but it turns out that wouldn’t work because i need to launch Firefox with Selenium to test the flash player.

I found this cool built-in Mac tool called Automator. You can set up all sorts of tasks into a workflow. I just needed a simple shell script:

And now, we can call that from a cron job every 30 minutes! You might have to hunt around a bit for where it saves the file. For me it’s in my Library/Services.

*/30 * * * * automator /Users/daniea16/Library/Services/IVP\ Test.workflow

Another creative alternative to the cron job is to set up recurring calendar appointments in iCal. You can set an alarm that runs a script. Pretty awesome, hey?! :)

I know Cucumber is meant to be a BDD framework, and was never intended to be used for automated regression testing or assurance testing, but isn’t it cool that with a little bit of imagination you can bend it to fit these alternative uses? :)

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