Drooling Over Docker #3 - Docker CLI Structure & Management Commands

Prior to Docker 1.13 release (January 2017), docker commands were logically grouped around the purpose e.g. build, ship, or run commands; however this list of commands was quite unstructured and often confusing for the lack of context they would operate inside of e.g. for a certain command, it was difficult to determine whether it would run on an image or on the container spawned from that image. A detailed list for few such challenges in using earlier Docker CLI can be seen here.

With Docker 1.13 release, the Docker commands are given a structure where a command has three parts (with a few exceptions) in addition to other options or arguments as needed -

$ docker

The command "$ docker image ls" has the following components:

• The docker client command - docker
• To provide a context, management command e.g. image
• The sub-command to inform of the specific action required e.g. ls to list the downloaded docker images

Let us see how these commands look like at the terminal:

Listing downloaded Docker images

Removing one of the downloaded images

The following list presents all management commands available in the current docker version:

Each of the above listed management commands has a set of sub-commands to initiate a specific action; the following screen-shot shows the sub-commands under management command image :

The following table shows all available docker image commands:

Though the earlier Docker commands are compatible with the newer Docker versions, the new commands are easier to remember and invoke. The following table shows a comparison between earlier (still working) vs. newly structured commands -

Contd...

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Resources:

1. Docker 1.13 Management Commands
2. Docker Management Commands by Romin Irani
3. Working with Docker v1.13 CLI -Management commands
4. Docker CLI documentation