Change Capybara.server settings to use Puma


I have a Rails 5 project that is now using some ActionCable stuff in order to implement some features on the UI. The inclusion of ActionCable on the UI responses made some feature tests fail so I solved that on my local computer by setting the Capybara.server to use :puma, which basically means adding this line to the rails_helper.rb file:

Capybara.server = :puma

This allows the tests environment to deal with the threads that works with ActionCable, making the feature tests work as expected with the inclusion of ActionCable.

Now the big question is how do I set this so that the tests run on CircleCI also uses puma server for Capybara, if this is at all possible.

Or in other words, how could I do to run ActionCable features while running the tests on CircleCI?

I hope I explained this clearly enough.

Thanks in advance!

Ok so I got some help from the CircleCI support team and the solution to this is to include

- gem install puma

to the circle.yml and upgrading to ubuntu 14.04 (we had postponed the upgrade from 12 to 14 but that helped solve the issue)