This repo provides a simple way to setup a Ruby/Cucumber/Capybara/Selenium-Chrome based BDD environment.
See support/env.rb
for the magic.
Open a terminal in root directory and follow these steps:
# Use docker compose to start start the two services
# and open a bash session in the 'ruby' service:
docker-compose run ruby bash
# Note: This could take a few min the first time you run...
# To see the browser, connect to the second container via VNC
# The password is 'secret'.
# From the Finder: Go > Connect to server (cmd+k)
# You can also open a NEW terminal session and run this command:
open vnc://:[email protected]:5900
# Back in the original terminal session, we're now inside our ruby service.
# Run the tests with cucumber
cucumber
# When you're done, you can exit the ruby container
exit
# Now (from the host machine) stop all the containers
docker-compose down
The basic components of BDD are:
- A running application to test (usually a web app)
- A web browser (like Chrome) to render the app and give access to the UI elements
- A web driver (like Selenium) to drive the browser
- A testing framework (like Capybara) to examine (and interact with) elements on the page
- A BDD framework (like Cucumber) to describe our tests (using Gherkin syntax), run them for us, and report on the results.
- Some language to define the step definitions and tie everything together (in this case, Ruby)
Docker compose makes it easy to package all the components into a couple of simple services (containers) and mount your source code into the containers from the host, without installing anything locally.
- The first service (which we'll call 'ruby') will hold the ruby runtime and any gems we need (e.g. cucumber and capybara). We'll build this with our Dockerfile.
- The second service will be an instance of the stand-alone Selenium-Chrome container.
Because the standalone-chrome-debug
Chrome container gives you a full Ubuntu environment, you can view (and interact with) the running browser via VNC. This is helpful for debugging and writing new tests.
You may have "Screen sharing" enabled on your mac. Go to "Settings" > "Sharing" and untick the "Screen Sharing box"
docker-compose run ruby cucumber
You can add a step And I debug
to your features to open the pry interactive debugger which lets you write code to interact with the browser in real-time without restarting your tests.
If you don't need to see the browser, you can use a smaller/faster headless Selenium container:
docker run -d -p 4444:4444 -p 5900:5900 selenium/standalone-chrome
You can manually start a browser session in the Selenium container:
- Browse to http://0.0.0.0:4444/wd/hub
- Click "Create session"
- Select "Chrome"
- Connect via VNC (see above)
open vnc://:[email protected]:5900