Misterio: so what?

Docker-compose based Ansible/SaltStack/NameYour minimalistic alternative. It is super-easy to use.

Misterio is a set of two tiny bash script you can use to "apply" a set of roles to a infinite numbers of hosts. Less then 100 lines of bash code (sorry Ansible :)

Misterio is able to manage a set of compose target as an one, appling status changes easily.

Why?

1. The only dependency is a recent version of docker.
2. It does not rely on docker swarm or on K8s. It can run even on ultra-small nano containers on Amazon, provided you have little swap (tested)
3. It is agent-less. It depends only on docker and bash on the target.
4. Everything must be versioned to work: you cannot easily "forget" something on your local machine.

How

For every hostname, define a directory inside hosts/ Put in it an env file based on this syntax:

<rolename>[@inst].env

where @inst is OPTIONAL and can be used to have multiple instances on the same machine.

The magic

For every role on the target machine misterio will:

1. copy the correct env file.
2. pass the command you provide to docker-compose
3. fail fast or loop

The "apply" pseudo-command will do a build and up in one step

NEW! You can use the pseudo command --list to get the list of all the roles, and the -- syntax to apply command only to a role.

Distributed

A misterio-ssh demo script is provided to show how to propagate it on a set of remote hosts. Misterio ssh needs a misterio command followed by a list of targets:

./misterio-ssh apply pi@raspy1 peter@mayhome parker@newserver
./misterio-ssh logs pi@raspy1 peter@mayhome parker@newserver
./misterio-ssh down pi@raspy1 peter@mayhome parker@newserver

Misterio-ssh is quite smart; for every target it will

1. Clone an ultra-small version of the repository and send it over the wire to the selected target misterio-ssh will try to use rsync and fallback to scp if needed
2. Remote launch it
3. Stop if an error occurs before step (1) Proceed to the next target if it fails

The Bonus

Misterio is also a collection of ready-made docker-compose infrastructure you can jump into. For instance, jenkins-with-docker show you how to get a dockerized-jenkins with:

• self running git server
• access to docker daemon to self-build stuff using docker plugin

Tips

Under docker for Windows, add COMPOSE_CONVERT_WINDOWS_PATHS=1 to your env path if you plan to bind stuff like

/var/run/docker.sock:/var/run/docker.sock

This will enable your roles to run on Windows and on Linux dameons seamlessly. See https://stackoverflow.com/a/52866439/75540 for more details

The Hype

1. It is trivial to parallelize misterio-ssh or the replace docker compose with K8s clusters (try and push me back).
2. You can add git submodules below roles/ to link recipes (your personal "ansible galaxy" is docker hub!)
3. No complex stuff to learn: it is just DOCKER!

Other alternative

https://github.com/piku/piku is an heroku-like alternative, based on python and not requiring docker.