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

Brewfile

tap "caskroom/cask"

cask "google-chrome"
cask "firefox"

brew "chromedriver"
brew "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'

gem 'selenium-webdriver'
gem 'capybara'
gem 'rspec'

Thank you bbonamin and dancristianb for saving me tons of time as I update an old Rails app's webdrivers gem from 4.2.0 - with the tap syntax - to 5.3.1 - with this one! 🥳👏👏👏

You might want to use the new headless mode in Chrome:

options.add_argument('--headless=new')

Also don't forget other default driver options.