Capybara Selenium Webdriver: Headless Chrome (with file downloads!) & Headless Firefox

Brewfile

brew tap "homebrew/cask"

brew install google-chrome
brew install firefox

brew install chromedriver
brew install geckodriver

chrome.rb

require 'capybara/rspec'
require 'selenium/webdriver'

options = Selenium::WebDriver::Chrome::Options.new
options.add_preference(:download, prompt_for_download: false,
                                  default_directory: '/tmp/downloads')

options.add_preference(:browser, set_download_behavior: { behavior: 'allow' })

Capybara.register_driver :chrome do |app|
  Capybara::Selenium::Driver.new(app, browser: :chrome, options: options)
end

Capybara.register_driver :headless_chrome do |app|
  options.add_argument('--headless')
  options.add_argument('--disable-gpu')
  options.add_argument('--window-size=1280,800')

  driver = Capybara::Selenium::Driver.new(app, browser: :chrome, options: options)

  ### Allow file downloads in Google Chrome when headless!!!
  ### https://bugs.chromium.org/p/chromium/issues/detail?id=696481#c89
  bridge = driver.browser.send(:bridge)

  path = '/session/:session_id/chromium/send_command'
  path[':session_id'] = bridge.session_id

  bridge.http.call(:post, path, cmd: 'Page.setDownloadBehavior',
                                params: {
                                  behavior: 'allow',
                                  downloadPath: '/tmp/downloads'
                                })
  ###

  driver
end

Capybara.javascript_driver = ENV['GUI'] ? :chrome : :headless_chrome

firefox.rb

require 'capybara/rspec'
require 'selenium/webdriver'

Capybara.register_driver :firefox do |app|
  Capybara::Selenium::Driver.new(app, browser: :firefox)
end

Capybara.register_driver :headless_firefox do |app|
  options = Selenium::WebDriver::Firefox::Options.new
  options.headless! # added on https://github.com/SeleniumHQ/selenium/pull/4762

  Capybara::Selenium::Driver.new app,
    browser: :firefox,
    options: options
end

Capybara.javascript_driver = ENV['GUI'] ? :firefox : :headless_firefox

Gemfile

source 'https://rubygems.org'

group :development, :test do
  gem 'factory_bot_rails' # Sample data, skip if you intend to use fixtures
  gem 'rspec-rails', '~> 5.0.0'
end

group :test do
  # For enabling database-cleaning on js:true system/feature spec
  # because the automatic transaction done by rspec will not be capable of
  # cleaning it on js: true. Setting the cleaning method of Rspec to :truncation will work
  # but it will significantly increase the suite runtime.
  # Read more: https://avdi.codes/configuring-database_cleaner-with-rails-rspec-capybara-and-selenium/
  # and more in-depth technical nitty-gritty: https://stackoverflow.com/a/15976982
  gem 'database_cleaner'
  gem 'capybara'
  # Drivers
  gem 'selenium-webdriver'
  # To keep the webdrivers above up-to-date by auto installing the updates
  gem 'webdrivers', '~> 4.0', require: false
  gem 'webmock'
end

rails_helper.rb

# This file is copied to spec/ when you run 'rails generate rspec:install'
require 'spec_helper'
ENV['RAILS_ENV'] ||= 'test'
require File.expand_path('../config/environment', __dir__)
# Prevent database truncation if the environment is production
abort("The Rails environment is running in production mode!") if Rails.env.production?
require 'rspec/rails'
# Add additional requires below this line. Rails is not loaded until this point!

require 'capybara/rspec'
require 'selenium/webdriver'
require 'webmock/rspec'
# these lines below required to make chromedriver works
WebMock.disable_net_connect!(
  allow: ['chromedriver.storage.googleapis.com', 'localhost', '127.0.0.1']
)

#
# You can put the Capybara driver settings here if you want
#

# Important line to uncomment if you want to include all support files by default
Dir[Rails.root.join('spec', 'support', '**', '*.rb')].sort.each { |f| require f }

begin
  ActiveRecord::Migration.maintain_test_schema!
rescue ActiveRecord::PendingMigrationError => e
  puts e.to_s.strip
  exit 1
end
RSpec.configure do |config|
  ### === SAMPLE data generation === ###
  # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
  # config.fixture_path = "#{::Rails.root}/spec/fixtures"
  config.include FactoryBot::Syntax::Methods
  ### === END SAMPLE data generation === ###

  ### === DATABASE_CLEANER gem setting === ### 
  # If you're not using ActiveRecord, or you'd prefer not to run each of your
  # examples within a transaction, remove the following line or assign false
  # instead of true.
  config.use_transactional_fixtures = false # CHANGE from true to false

  # You can move this utilities to support folder if you want, like `database_cleaner.rb`
  # then add `require 'database_cleaner'`
  
  # This says that before the entire test suite runs, clear the test database out completely. 
  # This gets rid of any garbage left over from interrupted or poorly-written tests
  config.before(:suite) do
    DatabaseCleaner.clean_with(:truncation)
  end

  # This part sets the default database cleaning strategy to be transactions. 
  # Transactions are very fast, and for all the tests where they do work—that is,
  # any test where the entire test runs in the RSpec process—they are preferable.
  config.before(:each) do
    DatabaseCleaner.strategy = :transaction
  end

  # By default, these are the only tests for which Capybara fires up a test server process and
  # drives an actual browser window via the Selenium backend. For these types of tests,
  # transactions won’t work, so this code overrides the setting and chooses the “truncation” strategy instead.
  config.before(:each, :js => true) do
    DatabaseCleaner.strategy = :truncation
  end

  # These lines hook up database_cleaner around the beginning and end of each test,
  # telling it to execute whatever cleanup strategy we selected beforehand.
  config.before(:each) do
    DatabaseCleaner.start
  end

  config.after(:each) do
    DatabaseCleaner.clean
  end
  ### === END DATABASE_CLEANER gem setting === ### 
end