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by edwardmcfarlane 1118 days ago
Better templating, example https://github.com/emcfarlane/kubestar which uses starlark for kubernetes config.
4 comments

The firm I work at developed an internal library (open source soon hopefully!) that does all our templating in Python, example:

  import os

  """
  Imports redacted, but this imports our library
  """

  NAME = "my_app"
  PORT = 5000
  DEPLOY_ENV = os.environ["DEPLOY_ENV"]

  deploy_all(
      create_stateful_service(
          NAME, http_port=PORT, cpu=2000, memory=500
      ),
      create_ingress(
          NAME,
          service_name=NAME,
          service_port=PORT,
          hostnames=["myapp.internal.com"],
      ),
  )

In the background, this converts a bunch of objects to YAML, leveraging the fact that objects in Python are just dictionaries. It then takes these objects and sends them to the K8S API. Really improved our DevEx since you can do complex tasks like "define a deployment, deploy it, and then check server status" because it is all just Python at the end of the day.

Edit: formatting

I wrote something similar using Ruby a while back. https://github.com/matsuri-rb/matsuri

I even have a helm plugin that would let you specify all the command line options and values so that it can be tracked in git and consistently applied

There’s also tools for transforms on raw manifests so you can track changes (in code) from upstream manifests

I was tinkering with a similar approach to this, using Python objects to generate the YAML. I'm not working in it right now, but I'd love to see other tools use this approach.
Nice, I've seen similar setups like this with Go before. Maybe that's the better way to do it, use a proper language instead of yamls for config.
It should be like that from the very beginning, any and all configuration management systems that chose YAML as base instead of DSL (even if DSL is just a subset of Python or Lua) have same problems.
https://github.com/kapicorp/kapitan is also a very powerful option for managing and generating templates.
What do you use templating for that made you not want to use Helm? Granted it's buggy as hell, but the fact that it automates so much operational process makes it save way more time over templating, in my experience.
Using Helm made me not want to use Helm! Joking, Helm is what I would use but still think there is a better way to do templating. This tool scratches that itch.
We use CUE directly to generate yaml resources

Have our eyes on Timoni

https://github.com/stefanprodan/timoni

CUE is really interesting in comparison with protobuffers with CEL. Thanks for linking the project.
you're welcome, I also maintain https://cuetorials.com