github-workflows-kt VS config

We use Kotlin to generate the yaml for our github actions: https://github.com/typesafegithub/github-workflows-kt

Nothing like a good old type safe compiled language to cut down on the verbosity, copy paste usage, silly syntax errors, weird undocumented you just have to know the magical incantations, etc. Kotlin or similar languages are the way to go. Much safer, more compact, easier to cut down on the copy paste reuse (which is just miserable drudgery), easy to introduce some sane abstractions where that makes sense. You get auto completion. And if it compiles, it's likely to just work.

People keep on moving around the deck chairs on the proverbial Titanic when it comes to configuration languages. Substituting yaml for json or toml just moves the problems. And substituting those with XML just introduces other issues and only marginally improves things. Well formed xml is nice. But so is well formed json. Schemas help, if the urls don't 404 and you have tools that can actually do something with them. Which, as it turns out is mostly not a thing in practice. And without that, it's just repetitive bloat. XML with schemas becomes very hard to read quickly.

There's a reason, people started ignoring XML once json became popular: json does most of the essential stuff well enough that XML just isn't worth the effort. And if you have something where you'd actually need the complexity of XML, it's likely to be some really ugly bloated kind of thing where the last thing you'd want to do is edit it manually.

I've dealt with cloudformation in XML form at some point in my life. It sucks. Not just a little bit. It's an absolute piss poor format for a thing like that. Since such a thing was lacking at the time, we ended up actually building our own little tools to generate that xml. Hand editing it was just too painful. One mistake could corrupt your entire stack. And it takes ages to find out if you actually got it right. In Json form it's hardly any better. It's just one of those convoluted over-engineered things. Anyway, Json support for cloudformation was not there at the time and the difference is like asking whether you'd preferred to be shot or stabbed. It's going to suck either way.

github-workflows-kt is a tool for creating GitHub Actions workflows in a type-safe script, helping you to build robust workflows for your GitHub projects without mistakes, with pleasure, in Kotlin.

The github-workflows-kt project uses Kotlin scripting, and it recommends doing everything using main.kts, because it's easier.

I use matrix tests with github actions to test my kt-search client with different versions of elastisearch and opensearch. Pretty easy to set up: https://github.com/jillesvangurp/kt-search/blob/master/.gith...

Basically it fires up elasticsearch using docker-compose and then the integration tests run against that. You could use a similar strategy to test different feature flag combinations.

For some of our private projects, we use kts to generate the github action yaml files using this: https://github.com/krzema12/github-workflows-kt

Well worth checking out if you have more complex workflows. Yaml is just horrible in terms of copy paste reuse. Also nice to get some compile time safety and auto complete with our action files.

One of my team members, Nikky, got annoyed with the verbosity and insane amount of copy-paste reuse needed to drive Github Actions. And true to her nature, promptly fixed it by using and contributing to GitHub Actions Kotlin DSL

GitHub: https://github.com/krzema12/github-actions-kotlin-dsl

I don‘t understand why HOCON (https://github.com/lightbend/config/blob/main/HOCON.md) isn‘t used more often (at least for configuration use cases). It‘s a superset of JSON, has comments, multiline strings, optional quotes, replacement syntax. We use it at many places, and it‘s as nice at it can get.

HOCON is a great human-readable alternative to JSON. It's a superset of JSON with lots of cool features that make it both more readable and easier to use.

Here's a rundown of HOCON's main features: https://github.com/lightbend/config#features-of-hocon

"Typesafe Config" is the library generally used to read configuration files in HOCON format, which this library introduced. It's commonly used in essentially OOP/imperative Scala contexts, including Akka and its ecosystem.

Interesting!

For my own servers I use an internal tool that integrates apps with systemd. You point it at the output of your build system and a config file, and it produces a deb that contains systemd unit files and which registers/starts the server on install/reboot/upgrade, as a regular debian package would. Then it uploads it to the server via sftp and installs it using apt, so dependencies are resolved. As part of the build process it can download and bundle language runtimes (I use it with a JVM), it scans native binaries to find packages that the app should depend on, and you can define your config including package metadata like dependencies and systemd units using the HOCON language [1].

Upshot is you can go from a Gradle or Maven build to a running server with a few lines of config. Oh and it can build debs from any OS, so you can push from macOS and Windows too. If your server needs to depend on e.g. Postgres, you just add that dependency in your config and it'll be up and running after the push.

It also has features to turn on DynamicUser and other sandboxing features. I think I'll experiment with socket activation next, and then bundled BorgBackup.

Net/net it's pretty nice. I haven't tried with containers because many language ecosystems don't seem to really need them for many use cases. If your build tool knows how to download your language runtime and bundle it sans container by just setting up paths correctly, then going without means you can rely on your Linux distribution to keep things up to date with security patches in the background, it means networking works as you'd expect (no accidentally opened firewall ports!) and so on. SystemD knows how to configure resource isolation/cgroups and kernel sandboxing, so if you need those you can just write that into your build config and it's done. Or not, as you wish.

With a deployment tool to automate builds/pushes, systemd to supervise processes and a big beefy dedicated machine to let you scale up, I wonder how much value the container part is really still providing if you don't need the full functionality of Kubernetes.

[1] https://github.com/lightbend/config/blob/main/HOCON.md

Other similar standards: TOML, HOCON

I've also used HOCON pretty extensively for config, and it is better than both YAML and JSON for config with moderate to high complexity.