Learning Docker by doing examples.

Starting with examples found in http://training.play-with-docker.com/

First step:

Hello world app - run command docker container run hello-world

workflow was like this:

• download image (by Docker Deamon)
• create container based on that image (by Docker Deamon)
• run executable in that image (run by whatever is in that container)
• display the output of execution in console (streamed by Docker Deamon, but captured and displayed by Docker Client)

Basic commands

• docker image ls -list all images download to current file system
• docker image pull - pulls image from registry (Default registry is 'Docker Registry', Default tag is 'latest')
• [winpty] docker run -it - runs interactive terminal based on image name. Example 'docker run -it alpine apk'. winpty is optional, applies only for Windows environments. This is one-off command, after that the container is shutdown. If you provide -it, then docker will make sure that the interactive shell is provided. Otherwise "nothing would happen".
• docker ps -a - list all containers and their statuses -docker-compose -f ps - list status of containers specified in the