• selenium-standalone server
  • Dockerfile
  • Build image
  • Use image
    • Parameters
    • Healthcheck
      • Use cases

selenium-standalone Server with Chrome and Firefox

Dockerfile

docker build -t webdriverio/selenium-standalone . --rm

$ docker run -it -p 4444:4444 webdriverio/selenium-standalone

• SCREEN_GEOMETRY Set browser window size

  • Format: <WIDTH>x<HEIGHT>x<DEPTH>
  • Default: 1920x1080x16
  • Usage example: set screen size to 1200x1200 with 8bits depth

    $ docker run -it -p 4444:4444 -e SCREEN_GEOMETRY="1200x1200x8" webdriverio/selenium-standalone
    

• DEBUG Enable selenium-standalone debug messages

  • Value: selenium-standalone:*
  • Default: null
  • Usage example:
    • Enable debug when building the image

    $ docker build --build-arg DEBUG=selenium-standalone:* -t webdriverio/selenium-standalone . --rm
    

    • Enable debug when running the image

    $ docker run -it -p 4444:4444 -e DEBUG="selenium-standalone:*" webdriverio/selenium-standalone
    

A Docker healthcheck is defined when the image is built.

This defines a health status attached to the running container. It checks that Selenium server ready status is true

• Manually check the status of a running webdriverio/selenium-standalone container

  docker ps
  

  Check STATUS property, health status is displayed at the end (between parenthesis)

• When running the image in detached mode you want to ensure that the Selenium server is ready before using it.

  Here is a way to poll check container health status until it's healthy:

  # Start container in detached mode, forcing its name to `sel-std`
  docker run --rm --name=sel-std -d -p 4444:4444 webdriverio/selenium-standalone
  
  # Will loop until container `sel-std` (you can also check via container id) health status is exactly `healthy`
  while ! docker inspect --format='{{json .State.Health}}' sel-std | grep -sq '"healthy"'; do sleep 1; done