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Comment by tdurden | Hacker News Reader

You can already run whatever commands you want when creating a Docker image, including your own shell scripts. It isn't clear to me why one would want to use this.

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You are right, deck-build doesn't have any magic regarding the build process (this is part of the concept). But:

1.) It bundles a lot of useful functions (https://bit.ly/2N9mAEu) in the "kit": Have a look at this gist: https://bit.ly/2Nby0HZ - Four lines to create a container with two users (foo and root) including their own python packages installed in their home directories (PIP_USER=1).

2.) It's very easy to expand the kit and the plan/artefact concept helps to structure and reuse code (https://bit.ly/2BEIcnH) stored on your local disk or in repositories.

I think you may have inadvertently proven my point. This kind of abstraction is completely unnecessary. You could have added users and installed requirements in a similarly small amount of Dockerfile commands.

Why would I use this tool for 1) instead of Make or just throw CMD useradd -m foo into my Dockerfile?

Yes, your are both right, of course you can RUN "useradd ...". But we have often made the experience that we need to run more complex processes during docker builds (with if...else conditions etc.) resulting in complex Dockerfile RUNs. Bundling and reusing this code in plans/artefacts is very useful. In the end we use docker-build to create our images, of course it's not intended to be a substitution for the great (docker hub) image concept.

But we have often made the experience that we need to run more complex processes during docker builds (with if...else conditions etc.) resulting in complex Dockerfile RUNs

That's fair, I've come across those types of scenarios as well, but trying to solve them during docker build seems like you're giving yourself, and inheritors of your docker image a lot of unnecessary extra work. Shouldn't those processes be solved independently of the docker daemon, and the results fed to Docker when it's ready for them?

I am not sure if I understand your comment correctly, but we all know that there is a very large range of image requirements. Some of them need to be solved during builds (e.g. sometimes you want to distinguish between dev and production setups), other will be processed during container setup.

You are right regarding inheritors. Creating a docker-hub image has differnent requirements than creating images for your private environment.

I guess I'm not entirely understanding how the scenarios you bring up to myself and others aren't sufficiently solved in the current Dockerfile implementation, along with other command-line tools that I can use immediately or retrieve trivially. A 'framework' for bash + docker feels a bit anti-pattern-y/or at least the benefits just aren't obvious for the way my team uses Docker presently.

That said, if what you've put together has solved problems for your team, maybe it will for others, so don't let my incredulity spoil anyone else's curiosity who reads these comments later.

In the meantime I have realized that the term "framework" is very missleading... ;) But you're pointing out a crucial point. IMO, the need of many Show-HN solutions is often not fully understandable in the first moment. But when processes and requirements change over time, sometimes these solutions are remembered again and can be a starting point for own ideas. That's one of the reasons why I read HN :) Thank you for your constructive comments!

when processes and requirements change over time, sometimes these solutions are remembered again and can be a starting point for own ideas.

You have a good point, here. Thanks for the responses and helping me understand your work a bit better!

Looks to be the type of thing where people didn’t want to learn a new technology so someone wrote a “framework” to make it “easier” for them.

Abstractions over abstractions over abstractions. Shaking my damn head.

I’ve only been in the industry 7 years or so, but I’ve already begun to prefer sticking with standard operating procedures - like using Dockerfiles for Docker, or using Swift to build iOS apps instead of react-native, because in my experience, if you don’t constantly maintain and stay on top of something that isn’t built with the officially-supported tooling, it’s going to be a lot more trouble when you have to eventually change something. Especially if that change is years down the road and when you finally need to make it, your build system was built on some esoteric unsupported third-party tool that people lost interest in two years ago and stopped developing. Not saying that’s what this is... just a warning.

It’s cool to make new stuff and all that, especially when you have a real repetitive problem that isn’t solved elsewhere, but sometimes it seems like people are making problems up or creating solutions to problems that aren’t really problems in the first place. I’m tired of new stuff. I don’t want flashy. I want reliable, stable, usable things with excellent tooling around them. I don’t want something that downloads 300 packages from npm and breaks when I try to update it later and some unknown dependency that wasn’t hard-pinned gets updated in my app. Why things aren’t hard-pinned by default blows my mind. It seems like every time I have to work on a JavaScript application I run into problems like this, which is part of why I hate that juvenile ecosystem. And lack of typing information doesn’t help. At least with typed languages, if something gets upgraded that shouldn’t have been, the IDE or compiler will catch the error usually. And this is all coming from a Python guy (historically). Don’t even get me started on pipenv.

/rant

No, it's not "easier" and it doesn't replace the thinking in images and using images in the final step. The user really need to understand the docker concept. As I wrote in the other answers: It's only (another) approach to avoid complex (RUN ... if ... else ...) Dockerfiles. Hey, this is HN: We share solutions. some you like, some you don't - But the ones you don't like will give you new ideas sometimes :)

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