Table of contents

1. Docker
   1. What is a Docker
   2. Installation of Docker
   3. What is a Container?
   4. What is an image?
   5. Build a Docker Container:
      1. Necessary files:
   6. Create a Container
   7. Start a Container
   8. Run a command on a docker container
   9. List all Docker Container
   10. Stop a Docker Container
   11. Remove a Docker Container

Docker

What is a Docker

Docker enables you to separate your applications from your infrastructure, so you can deliver software quickly. The programmings’ language for Docker is GO.

Installation of Docker

Docker is available on different operations systems. Follow this guide to install Docker.

What is a Container?

A Container is a process, that has been isolated from the processes on the host machine.

What is an image?

An image is a filesystem of a docker Container, that also has been isolated from the filesystem of the host machine. There are all dependencies, config files, scripts and binaries from the running Application saved.

Build a Docker Container:

Necessary files:

• The file package.json lists all dependencies that the running application needs
• The file Dockerfile is the description for Docker how to build the Docker Container

docker build -t getting-started . is the command to build a Container from the current folder and name it “getting-started”. The argument -t name gives the Container a name.

Create a Container

To build a Docker Container you need the command docker run <name>. useful arguments:

• -d this starts the Container in the background (“detached” mode)
• -p 3000:3000 maps the port 3000 of the Container to the port 3000 of the host system, to make it available from outside the Container.

Start a Container

To start the created docker container you can use the command docker start <container_name>.

Run a command on a docker container

To run a command on a docker container you can use the command docker exec -it <container_name> <command>. You can for example start a shell with this command: docker exec -it <container_name> sh.

List all Docker Container

docker ps lists all Containers with some information.

Stop a Docker Container

docker stop <the-container-id> stops a Container. You can get the ID of the Container with the command docker ps.

Remove a Docker Container

docker rm <the-container-id> removes the Container with the given ID. You need to stop the Container first. To stop it automatically, add the argument -f.