kustomize VS tanka

kustomize: brew install kustomize

It's a built in feature of kustomize https://github.com/kubernetes-sigs/kustomize/blob/master/api/types/helmchartargs.go

I think the combination of Kustomize and helm works in my experience. For advanced use cases, you can also see KRM functions in Kustomize.

See for instance a related issue: https://github.com/kubernetes-sigs/kustomize/issues/3866

Using a strategic merge is the safest way so you avoid the index fragility.

Rendering out the manifests is something I have been pushing for. Not having to understand how every templating tool works and what actually is being changed is key. Though, it gets complicated when you use helm (or any templating/patching tool) that produces many variants. You also lose any release/deployment time hooks that are provided (helm hooks or recently "patched" kustomize env variables).

https://github.com/kubernetes-sigs/kustomize/blob/master/examples/chart.md (edit: oh I see the other commenter also included this link, oops)

Kustomize is an open-source project that “lets you customize raw, template-free YAML files for multiple purposes, leaving the original YAML untouched and usable as is.” It’s now the most popular tool for customizing Kubernetes manifests reasonably, and it’s even built directly into the Kubernetes CLI since K8s v1.14.

I would recommend implementing a similar API to Grafana Tanka: https://tanka.dev

When you "synthesise", the returned value should be an array or an object.

1. If it's an object, check if it has an `apiVersion` and `kind` key. If it does, yield that as a kubernetes object and do not recurse.

Maybe you'd like jsonnet: https://jsonnet.org/

I find it particularly useful for configurations that often have repeated boilerplate, like ansible playbooks or deploying a bunch of "similar-but" services to kubernetes (with https://tanka.dev).

Dhall is also quite interesting, with some tradeoffs: https://dhall-lang.org/

A few years ago I did a small comparison by re-implementing one of my simpler ansible playbooks: https://github.com/retzkek/ansible-dhall-jsonnet

- validation is often impractical (at least identifying exactly where the error is… I’m looking at you Helm!)

Unrelated to OP, but you can leverage Tanka to extend helm charts with functionality not provided by upstream.

https://tanka.dev/

Although jsonette might be considered more complex Tanka is a great alternative for k8s config management.

At Grafana Labs we're using jsonnet at scale, while being a powerful functional language it is also excellent for rendering JSON/YAML config. We have developed Tanka[0] to work with Kubernetes, for other purposes I can recommend this course[1] (authored by me).

[0] https://tanka.dev/

[1] https://jsonnet-libs.github.io/jsonnet-training-course/

If you're hitting the limits of Kustomize, maybe look at Tanka as well.

Yes, try Tanka.

yes. basically. and this is a path that multiple people are trying to solve. e.g. AWS CDK8s, https://tanka.dev/, etc

Compose would be awesome.

http://tanka.dev

(Note I work for Grafana Labs who fund Tanka and use it for all production config)