Minimal (yet effective) Capybara + headless Chrome testing setup

spec_helper.rb

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

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

webdriver_options = %w(disable-gpu)
webdriver_options << 'headless' unless ENV['WINDOWED'] == 'true'

Capybara.register_driver(:headless_chrome) do |app|
  capabilities = Selenium::WebDriver::Remote::Capabilities.chrome(
    chromeOptions: { args: webdriver_options }
  )

  Capybara::Selenium::Driver.new(
    app,
    browser: :chrome,
    desired_capabilities: capabilities
  )
end

Capybara.register_driver(:mobile) do |app|
  device_name = ENV.fetch('device', 'iPhone 6')
  capabilities = Selenium::WebDriver::Remote::Capabilities.chrome(
    chromeOptions: {
      args: webdriver_options,
      mobileEmulation: { deviceName: device_name }
    }
  )

  Capybara::Selenium::Driver.new(
    app,
    browser: :chrome,
    desired_capabilities: capabilities
  )
end

Capybara.javascript_driver = :headless_chrome
Capybara.default_driver = :headless_chrome
Capybara.app_host = ENV['HOST']
Capybara.save_path = 'test_reports/'
Capybara.default_max_wait_time = 10

RSpec.configure do |config|
  config.include Capybara::DSL
  config.include Helpers
  config.after(:each) do |example|
    if example.exception
      errors = page.driver.browser.manage.logs.get(:browser)
      puts "Test failed, dumping browser logs:"

      # indent error messages by two spaces
      errors.map! { |error| "  #{error}" }
      puts
      puts errors.join("\n")
    end
  end
end

test.rb

require_relative 'spec_helper'

describe "Signing up for a wine subscription on desktop" do
  context 'on desktop' do
   it 'takes the user to the homepage' do
      visit '/'
    end
  end

  context 'on mobile', driver: :mobile do
   it 'takes the user to the homepage' do
      visit '/'
    end
  end
end