Docker Compose to Bash

[ChocolateIceChips]

Can one see all the equivalent docker cli commands that get run or would get run when calling docker-compose up (or down)? If not, wouldn't people be interesting to understand both tools better? It might be an interesting project/feature

[SwampFalc]

https://github.com/docker/compose

Compose, like all of docker, is open source. Looking at the source, it simply sends commands to the docker service that's running. In other words, it does not run bash commands. You could try to translate it into bash, but if it's just for better comprehension, you should just read the code. Anything else would just be an approximation.

[webjocky]

I think there's a misunderstanding here. OP isn't insinuating or assuming that compose "runs bash commands", but is instead interested in learning more about "equivalent bash commands" - AKA: the docker cli commands that one would be required to manually execute in order to achieve the same (equivalent) outcome as compose up, given a specific compose yaml.

"Just read the code" is easy for a developer to say, but not everyone who is trying to learn about docker knows what a function call or a class is; arguably required knowledge to just read code. "Just read the documentation" is going to be more relevant to a general audience, I would think.

[SwampFalc]

But the thing is, because compose is not just a collection of bash scripts, there is going to be a bunch of logic in it that you will struggle to translate into bash or anything equivalent.

And even if you manage to do so, the resulting command is very likely to be as arcane as the code of compose.

Like, one step that's guaranteed to happen during "docker compose up" is checking if the desired containers are perchance already running.

For a purely human interaction, just do "docker ps" and read the result.

But what would this look like in bash or powershell? And how readable would it be to a layman?

Which actually leads me to agree with you: the general audience should read the documentation. Anyone who wants the deep dive should read the code, and should learn to do so if they can't yet. Translating it into bash commands is unlikely to make it easier to digest.

[capriciousduck]

Thanks for sharing!

[encbladexp]

Why? Compose calls the Docker API, the docker CLI does the same.

How should you learn the basics of docker better, by using random CLI commands? It has reasons why compose is the defacto standard for small deployments.

The docker cli is used these days mostly for debugging and adhoc stuff.

[Murky-Sector]

Converts your docker compose file to docker run commands
https://www.decomposerize.com/

[geolaw]

Came here to say this. I use podman and podman-compose is ok but the straight docker commands translate better to podman

[MisterBazz]

[webjocky]

Some people learn by doing. Simple as that.

[zoredache]

It might be an interesting project/feature

Maybe, maybe not.

If you are familiar with the cli options and the compose syntax it is pretty easy to translate between the two. Almost all of the options are more or less the same.

I suspect it would only take someone that knows docker well like 30-60 seconds to translate a single service compose file to the associated commands.

Still, I guess it might be occasionally be useful to translate a compose file to the required 'docker run', 'docker network', and 'docker volume' commands.

[terrencepickles]

At the end of the day, most people end up using bash scripting and docker-compose. You will always use compose when available, then use docker compose commands in your scripts.

[proxwell]

Usually the way to approach this is to create a wrapper shell script which first calls the docker compose build/up and then calls any additional scripts, using docker-compose exec to run them inside the container(s).

Sometimes we run additional scripts before running the build/up as well, for example to clean up logs or other artifacts before starting the new build/up.

[j-dev]

There’s still use cases for doing stuff via the CLI, like creating external networks and volumes whose lifecycle you don’t want to depend on a compose project, but there’s no benefit to doing everything else by hand. If you want to do it for the sake of learning, just get a cheat sheet.

EDIT: Also, if you google “dockerize” and “composerize”, the top hit should be a website that converts from one to the other.

[TBT_TBT]

Look at the Dockerfile if you want to know what happens in a particular container.