Docker-compose testing with Selenium fails / Selenium::WebDriver::Error::UnknownError: unknown error: net::ERR_CONNECTION_REFUSED

Question

I am trying to run tests using Docker-compose, but I am having trouble with Selenium. I have no previous experience with docker so I am struggling with it.

Dockerfile

# syntax=docker/dockerfile:1
FROM ruby:2.7.2
RUN apt-get update -qq && apt-get install -y nodejs postgresql-client
WORKDIR /myapp
COPY Gemfile /myapp/Gemfile
COPY Gemfile.lock /myapp/Gemfile.lock
RUN bundle install

# Add a script to be executed every time the container starts.
COPY entrypoint.sh /usr/bin/
RUN chmod +x /usr/bin/entrypoint.sh
ENTRYPOINT ["entrypoint.sh"]
EXPOSE 3000

# Configure the main process to run when running the image
CMD ["rails", "server", "-b", "0.0.0.0"]

docker-compose.yml

version: "3.9"
services:
  db:
    image: postgres
    volumes:
      - ./tmp/db:/var/lib/postgresql/data
    environment:
      POSTGRES_PASSWORD: password
  web:
    build: .
    command: bash -c "rm -f tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0'"
    volumes:
      - .:/myapp
    ports:
      - "3000:3000"
    depends_on:
      - db
  selenium-hub:
    image: selenium/hub:3.141.59-20210913
    container_name: selenium-hub
    ports:
      - "4444:4444"
    expose: 
      - 4444
  chrome:
    image: selenium/node-chrome:3.141.59-20210913
    links:
    - selenium-hub
    container_name: chrome
    deploy:
      replicas: 1
    ports:
      - "5900:5900"
    volumes:
      - /dev/shm:/dev/shm
    depends_on:
      - selenium-hub
    environment:
      - HUB_HOST=selenium-hub
      - HUB_PORT=4444
      - JAVA_OPTS=-Dwebdriver.chrome.whitelistedIps=
      - NODE_MAX_INSTANCES=3
      - NODE_MAX_SESSION=3
  firefox:
    image: selenium/node-firefox:3.141.59-20210913
    container_name: firefox
    deploy:
      replicas: 1
    volumes:
      - /dev/shm:/dev/shm
    depends_on:
      - selenium-hub
    environment:
      - HUB_HOST=selenium-hub
      - HUB_PORT=4444

rails_helper.rb

ENV["RAILS_ENV"] ||= "test"
require File.expand_path("../../config/environment", __FILE__)
abort("The Rails environment is running in production mode!") if Rails.env.production?
require "spec_helper"
require "rspec/rails"
# Add additional requires below this line. Rails is not loaded until this point!
require "capybara/rspec"


# Dir[Rails.root.join("spec/support/**/*.rb")].each { |f| require f }

# Checks for pending migrations and applies them before tests are run.
# If you are not using ActiveRecord, you can remove these lines.
begin
  ActiveRecord::Migration.maintain_test_schema!
rescue ActiveRecord::PendingMigrationError => e
  puts e.to_s.strip
  exit 1
end

# Seting capybara for google chrome browser

selenium_host = "http://selenium-hub:4444/wd/hub"

unless ENV['SELENIUM_HOST'].nil?
  selenium_host = "http://#{ ENV["SELENIUM_HOST"] }:4444/wd/hub"
end

Capybara.register_driver :selenium_chrome do |app|
  # Capybara::Selenium::Driver.new(app, browser: :chrome)
  options = Selenium::WebDriver::Chrome::Options.new(args: %w[
    headless no-sandbox disable-gpu window-size=1920x1080
  ])
  Capybara::Selenium::Driver.new(
    app,
    browser: :remote,
    desired_capabilities: :chrome,
    options: options,
    url: selenium_host
  )
end

Capybara.server = :puma, { Silent: true }
Capybara.javascript_driver = :selenium_chrome
Capybara.save_path = "#{ Rails.root }/tmp/screenshots/"
Capybara.asset_host = 'http://localhost:3000'
Capybara.run_server = true
Capybara.configure do |config|
  config.match = :prefer_exact
  config.ignore_hidden_elements = true
  config.visible_text_only = true
  # accept clicking of associated label for checkboxes/radio buttons (css psuedo elements)
  config.automatic_label_click = true
end
Capybara.always_include_port = true

RSpec.configure do |config|
  # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
  config.fixture_path = "#{::Rails.root}/spec/fixtures"
  config.use_transactional_fixtures = true
  config.infer_spec_type_from_file_location!
  config.filter_rails_from_backtrace!

  config.before(:suite) do
    DatabaseCleaner.clean_with(:truncation)
  end

  config.before(:each) do
    DatabaseCleaner.strategy = :transaction
  end

  config.before(:each, js: true) do
    DatabaseCleaner.strategy = :truncation
  end

  # This block must be here, do not combine with the other `before(:each)` block.
  # This makes it so Capybara can see the database.
  config.before(:each) do
    DatabaseCleaner.start
  end

  config.after(:each) do
    DatabaseCleaner.clean
  end
end

Shoulda::Matchers.configure do |config|
  config.integrate do |with|
    with.test_framework :rspec
    with.library :rails
  end
end

After building and running containers, when I try to run the test command:

docker-compose run web bundle exec rspec

I am getting errors for tests with the selenium chrome driver:

Failures:

  1) Create new job offer when all fields are correct 
     Failure/Error: visit '/users/sign_in'
     
     Selenium::WebDriver::Error::UnknownError:
       unknown error: net::ERR_CONNECTION_REFUSED
         (Session info: chrome=93.0.4577.63)
     # #0 0x564856de3583 <unknown>
     # #1 0x564856b57a38 <unknown>
     # #2 0x564856b51e8d <unknown>
     # #3 0x564856b43ec6 <unknown>
     # #4 0x564856b44de3 <unknown>
     # #5 0x564856b44192 <unknown>
     # #6 0x564856b43774 <unknown>
     # #7 0x564856b42543 <unknown>
     # #8 0x564856b42893 <unknown>
     # #9 0x564856b593fa <unknown>
     # #10 0x564856bbdfaf <unknown>
     # #11 0x564856baa752 <unknown>
     # #12 0x564856bbd74c <unknown>
     # #13 0x564856baa643 <unknown>
     # #14 0x564856b80b94 <unknown>
     # #15 0x564856b81b85 <unknown>
     # #16 0x564856e13c6e <unknown>
     # #17 0x564856e29975 <unknown>
     # #18 0x564856e14bc5 <unknown>
     # #19 0x564856e2afb5 <unknown>
     # #20 0x564856e0984b <unknown>
     # #21 0x564856e46248 <unknown>
     # #22 0x564856e463c8 <unknown>
     # #23 0x564856e6073d <unknown>
     # #24 0x7f92b5c68609 start_thread
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/response.rb:72:in `assert_ok'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/response.rb:34:in `initialize'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:88:in `new'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:88:in `create_response'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/default.rb:114:in `request'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:64:in `call'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/bridge.rb:167:in `execute'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/w3c/bridge.rb:567:in `execute'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/w3c/bridge.rb:59:in `get'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/common/navigation.rb:32:in `to'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/selenium/driver.rb:104:in `visit'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/session.rb:278:in `visit'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/dsl.rb:53:in `call'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/dsl.rb:53:in `visit'
     # ./spec/features/create_job_spec.rb:7:in `block (2 levels) in <top (required)>'

  2) The expiring date when deadline is expired yet, date is not displayed
     Failure/Error: visit '/users/sign_in'
     
     Selenium::WebDriver::Error::UnknownError:
       unknown error: net::ERR_CONNECTION_REFUSED
         (Session info: chrome=93.0.4577.63)
     # #0 0x564856de3583 <unknown>
     # #1 0x564856b57a38 <unknown>
     # #2 0x564856b51e8d <unknown>
     # #3 0x564856b43ec6 <unknown>
     # #4 0x564856b44de3 <unknown>
     # #5 0x564856b44192 <unknown>
     # #6 0x564856b43774 <unknown>
     # #7 0x564856b42543 <unknown>
     # #8 0x564856b42893 <unknown>
     # #9 0x564856b593fa <unknown>
     # #10 0x564856bbdfaf <unknown>
     # #11 0x564856baa752 <unknown>
     # #12 0x564856bbd74c <unknown>
     # #13 0x564856baa643 <unknown>
     # #14 0x564856b80b94 <unknown>
     # #15 0x564856b81b85 <unknown>
     # #16 0x564856e13c6e <unknown>
     # #17 0x564856e29975 <unknown>
     # #18 0x564856e14bc5 <unknown>
     # #19 0x564856e2afb5 <unknown>
     # #20 0x564856e0984b <unknown>
     # #21 0x564856e46248 <unknown>
     # #22 0x564856e463c8 <unknown>
     # #23 0x564856e6073d <unknown>
     # #24 0x7f92b5c68609 start_thread
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/response.rb:72:in `assert_ok'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/response.rb:34:in `initialize'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:88:in `new'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:88:in `create_response'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/default.rb:114:in `request'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:64:in `call'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/bridge.rb:167:in `execute'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/w3c/bridge.rb:567:in `execute'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/w3c/bridge.rb:59:in `get'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/common/navigation.rb:32:in `to'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/selenium/driver.rb:104:in `visit'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/session.rb:278:in `visit'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/dsl.rb:53:in `call'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/dsl.rb:53:in `visit'
     # ./spec/features/display_expiring_date_spec.rb:22:in `block (2 levels) in <top (required)>'

  3) The expiring date when deadline is not expired yet, date is displayed
     Failure/Error: visit '/users/sign_in'
     
     Selenium::WebDriver::Error::UnknownError:
       unknown error: net::ERR_CONNECTION_REFUSED
         (Session info: chrome=93.0.4577.63)
     # #0 0x564856de3583 <unknown>
     # #1 0x564856b57a38 <unknown>
     # #2 0x564856b51e8d <unknown>
     # #3 0x564856b43ec6 <unknown>
     # #4 0x564856b44de3 <unknown>
     # #5 0x564856b44192 <unknown>
     # #6 0x564856b43774 <unknown>
     # #7 0x564856b42543 <unknown>
     # #8 0x564856b42893 <unknown>
     # #9 0x564856b593fa <unknown>
     # #10 0x564856bbdfaf <unknown>
     # #11 0x564856baa752 <unknown>
     # #12 0x564856bbd74c <unknown>
     # #13 0x564856baa643 <unknown>
     # #14 0x564856b80b94 <unknown>
     # #15 0x564856b81b85 <unknown>
     # #16 0x564856e13c6e <unknown>
     # #17 0x564856e29975 <unknown>
     # #18 0x564856e14bc5 <unknown>
     # #19 0x564856e2afb5 <unknown>
     # #20 0x564856e0984b <unknown>
     # #21 0x564856e46248 <unknown>
     # #22 0x564856e463c8 <unknown>
     # #23 0x564856e6073d <unknown>
     # #24 0x7f92b5c68609 start_thread
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/response.rb:72:in `assert_ok'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/response.rb:34:in `initialize'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:88:in `new'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:88:in `create_response'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/default.rb:114:in `request'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/http/common.rb:64:in `call'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/bridge.rb:167:in `execute'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/w3c/bridge.rb:567:in `execute'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/remote/w3c/bridge.rb:59:in `get'
     # /usr/local/bundle/gems/selenium-webdriver-3.142.7/lib/selenium/webdriver/common/navigation.rb:32:in `to'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/selenium/driver.rb:104:in `visit'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/session.rb:278:in `visit'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/dsl.rb:53:in `call'
     # /usr/local/bundle/gems/capybara-3.35.3/lib/capybara/dsl.rb:53:in `visit'
     # ./spec/features/display_expiring_date_spec.rb:7:in `block (2 levels) in <top (required)>'

Finished in 3.82 seconds (files took 1.13 seconds to load)
39 examples, 3 failures

Failed examples:

rspec ./spec/features/create_job_spec.rb:6 # Create new job offer when all fields are correct 
rspec ./spec/features/display_expiring_date_spec.rb:21 # The expiring date when deadline is expired yet, date is not displayed
rspec ./spec/features/display_expiring_date_spec.rb:6 # The expiring date when deadline is not expired yet, date is displayed

Randomized with seed 39822

ERROR: 1

Any help is very welcome.

Answer 1

The error means chrome driver is crashed and no longer available. As its issue with docker, the main reason will be that chrome is unable to start as its a GUI program and you are trying to run it from dokcer without GUI

You should be using any display server like xvfb

read more at:

https://praveendavidmathew.medium.com/running-webdriverio-in-wsl2-windows-91d3a0dc7746

Answer 2

If you are running linux/macos try doing this:

1. Update the docker-compose file as follows:

volumes:
  - "/tmp/.X11-unix:/tmp/.X11-unix:rw"
environment:
  - DISPLAY=:0
  - QT_X11_NO_MITSHM=1

2. Then make sure to don't have the --headless flag marked in the webdriver
3. Open a terminal and run:

xhost +
docker-compose up

Tested with Selenium::WebDriver::Firefox :)