Parallel Cucumber in Docker

How to run Cucumber tests in Parallel using Docker for Windows, Selenium Hub, and Jenkins

Getting started with Docker

Before trying to get this Docker solution running, I highly reccomend you run through the Docker getting started guide located here

Note: You might have to run through the getting started guide to get Hyper-V configured correctly

Note: In the getting started guide, when it comes to the docker-machine part, you might have to follow the instructions here for getting Docker Machine to work on Windows

Part 1: Getting Docker Set Up:

1. clone this repo, git clone https://github.com/ah0y/parallel_cucumber.git
2. open up an administrator version of hyper-v and powershell (then cd into the directory you've downloaded this repo to with powershell)
3. create 2 docker-machine vms (like in step 4 of the geting started guide)
   • docker-machine create -d hyperv --hyperv-virtual-switch "myswitch" --hyperv-memory "4096" myvm1
   • docker-machine create -d hyperv --hyperv-virtual-switch "myswitch" --hyperv-memory "2048" myvm2
   • Note: You might have to clean up the vms you've created from the getting started guide with docker-machine rm <vm-name> -f
4. run docker-machine ls and note your myvm1 ip address
5. run docker-machine ssh myvm1 "docker swarm init --advertise-addr <myvm1 ip>" to initialize your swam and get your docker swarm join command
6. run docker-machine ssh myvm2 "<docker swarm join command>" filling in the docker-swarm command with the output you've received in step 5. Make sure to change the port number on the very end of the join swarm command from 2376 to 2377 when joining a worker to a swarm
   • Note: The docker swarm join command needs to be in quotes
7. run docker-machine ssh myvm1 "docker node ls" to verify you've succesfully built the swarm
8. run & "C:\Program Files\Docker\Docker\Resources\bin\docker-machine.exe" env myvm1 | Invoke-Expression to configure powershell to execute commands on myvm1
9. run docker stack deploy -c docker-compose.yml parallel_cucumber to build the stack
10. Voila! Docker Swarm is now setup
    • visit <myvm1 ip>:8080 to access Jenkins (might take a minute to load)
    • visit <myvm1 ip>:4444/grid/console to access the Selenium Grid
11. after you've set up your Docker Swarm, scale chrome with docker service scale parallel_cucumber_chrome=10 (You should see the number of Chrome instances on the Selenium Grid increase)

Part 2: Getting Jenkins Set Up:

1. visit <myvm1 ip>:8080 to access Jenkins
2. run docker container ls
3. note the container id (column on the far left) of the jenkins-docker image
4. run docker exec -it <container id of jenkins-docker image> to access the Jenkins container
5. run cd /var/jenkins_home/secrets/
6. run cat initialAdminPassword to recieve the password to unlock Jenkins
7. copy the password you've recieved in step 6 into Jenkins and hit continue
8. install the suggested plugins
9. after the plugins are installed, continue as admin or setup an account. doesn't really matter
10. Voila! Jenkins is now setup

Part 3: Getting Jenkins to Build Dockerfiles and Run Cucumber Tests in Parallel:

1. on the Jenkins main menu, hit 'New Item' on the left hand side
2. enter in 'parallel_cucumber' for the item name
3. select 'Freestyle project' and hit 'Ok'
4. on the General tab (should be the default tab Jenkins takes you to), hit 'git' under 'Source Code Management'
5. copy the url for this repo into the 'Repository Url' field (https://github.com/ah0y/parallel_cucumber.git)
6. under build hit 'Add build step' and select 'Execute shell'
7. in the 'Command' text field, paste in docker build --build-arg GRID_IP=http://<myvm1 ip>:4444/wd/hub --build-arg NODES=10 -t parallel_cucumber . replacing myvm1 ip with your myvm1 ip
   • Note: 'http://' is required when specifying the IP for the docker build command
   • Note: Don't forget the '.' at the very end!
8. hit 'Save'
9. on the left hand side, hit 'Build Now' to build the test suite
10. Voila! You have now successfully run a test suite in parallel using Docker, Selenium Hub, and Jenkins

Notes:

• To add different physical machines to the docker swarm, just install docker on the additional machines and run step 3 and 6 from part 1 on each additional machine