Rails Travis CI Example

An example Ruby on Rails application configured to run Travis CI.

Configure Rails Application to run System Tests in Travis CI

Rails is configured by default to run system tests in Google Chrome. However, I ran into an issue with Travis CI when it came to running system tests using the default configuration. My solution was to update test/application_system_test_case.rb by declearing :headless_chrome instead of the default :chrome setting.

# test/application_system_test_case.rb
require "test_helper"

class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
  driven_by :selenium, using: :headless_chrome, screen_size: [1400, 1400]
end

Configure Travis CI

# .travis.yml
language: ruby
cache:
  - bundler
  - yarn
services:
  - postgresql
before_install:
  - nvm install --lts
before_script:
  - bundle install --jobs=3 --retry=3
  - yarn
  - bundle exec rake db:create
  - bundle exec rake db:schema:load
script:
  - bundle exec rake test
  - bundle exec rake test:system

Key	Description
os	Sets the build's operating system. Note that we did not add an `os` key, and are using the default environment
language	Selects the language support used for the build. We select `ruby` since this is a Rails project
cache	Activates caching content that does not often change in order to speed up the build process. We add `bundler` and `yarn` since Rails uses bundler and yarn to managage dependencies.
services	Services to set up and start. We add `postgresql` since our database is postgresql. You could also add `redis`.
before_install	Scripts to run before the install stage. We add `nvm install --lts` to use the latest stable version of Node. This will be needed when we run `yarn` later.
before_script	Scripts to run before the script stage. This sets up our Rails application. Note that I do not seed the database, since we only care about the test environment. I run `bundle install --jobs=3 --retry=3` instead of `bundle` becuase that's what the documentation recommends.
script	Scripts to run at the script stage. In our case, we just run our tests.