Containers vs VMs

• Container VS Virtual Machine
• Containers aren’t Mini-VM’s
• They are just processes
• Limited to what resources they can access (file paths, network devices, running processes)
• Exit when process stops

Docker CLI

• docker version
• docker info
• docker command line structure

docker <command> <sub-command> (options)

Let's create our first docker container

docker run -d mongo
docker container ls
docker run --name mongo -d mongo
docker run --name mongo -d mongo // Will throw an error
docker container ls
docker container logs mongo
docker container stop mongo
docker container stop [id of first mongo]

docker run --name mongo -d mongo // Will throw an error
docker start mongo
docker container stop mongo

docker container ls -a
docker container rm mongo
docker container ls -a

Image vs Containers

• An Image is the application we want to run
• A Container is an instance of that image running as a process
• You can have many containers running off the same image
• Docker's default image "registry" is called Docker Hub (hub.docker.com) 

docker container run --publish 80:80 nginx

• Downloaded image 'nginx' from Docker Hub
• Started a new container from that image
• Opened port 80 on the host IP

Integration with Testcafe

• TestCafe provides a preconfigured Docker image with Chromium and Firefox installed. Therefore, you can avoid manual installation of browsers and the testing framework on the server.

docker pull testcafe/testcafe

Prepare Tests

• Create a folder called dockerTests
• Create a file called test.js that opens zemoga website, navigate to jobs page.
• Try to submit the form
• Test for error message to appear 
• Something happened. Please make sure all the fields above are properly completed

Run TestCafe from the docker image.

docker run
    -v ${TEST_FOLDER}:/tests
    -it testcafe/testcafe ${TESTCAFE_ARGS}

docker run
    -v /path/to/dir/dockerTests:/tests
    -it testcafe/testcafe 'chromium --no-sandbox,firefox' /tests/test.js
    --rm