Indeed. Helm offers great features but it suffers from the kubernetes unnecessary complexity and by using golang templates in YAML.
When I started with kubernetes I converted my small Docker compose files to kubernetes files. Later I rewrote everything in helm charts. Now it's almost more YAML and golang templates lines than business logic lines in my applications.
I'm considering to go back to Docker compose files. It's simple, readable, and easy to maintain.
Highly recommend trying Jsonnet (via https://github.com/bitnami/kubecfg and https://github.com/bitnami-labs/kube-libsonnet) as an alternative. It makes writing Kubernetes manifests much more expressive and integrates better with Git/VCS based workflows. Another language like Dhall or CUE might also work, but I'm not aware of a kubecfg equivalent for them.
Jsonnet in general is a pretty damn good configuration language, not only for Kubernetes. And much more powerful than HCL.
If you like those, I'd take a look at Grafana's Tanka [0]. It also uses jsonnet but has some additional features such as showing a diff of your changes before you apply, easy vendored libraries using jsonnet-bundler, and the concept of "environments" which prevents you from accidentally applying changes to the wrong namespace/cluster.
I looked at it, I don't like it for the same reason as I dislike many other tools in this space: it imposes its own directory structure, abstraction (environments) and workflow. I'm a fan of the kubecfg-style approach, where it lets you use whatever sort of structure makes sense for you and your project.
It's a 'framework' vs 'library' thing, but in the devops context.
The problem with templating YAML is that you're templating text, in a very sensitive to whitespace syntax. By definition, Jsonnet avoids that because it operates on the data structure, not on their stringified representation.
My experience with jsonnet varied: there's good jsonnet code, and there's bad one, too. Just like with any programming language, you have to apply good software engineering practices. Text templated YAML, however, is terrible by design.
ytt is even more templating-yaml-with-yaml, so it all ends up being a bargain bin Helm. There's no reason to do this over just serializing plain structures into YAML/JSON/...
I'm aware, but I just don't understand the point of it. How is it in any way better than a purpose-specific configuration language like Dhall/CUE/Jsonnet? What's the point of having it look like YAML at all?
https://kapitan.dev/ is the one-stop shop that covers for true declarative configuration with either jsonnet, python (kadet) and jinja, amazing secret management with support of gkms, awskms, gpg, vault. It can also render helm charts!
It is simpler than other tools, because you can get started without even touching jsonnet or python or anything else, when using our generators.
It does more than all the other tools combined, as it replaces helm+helmfile+gitcrypt or kustomize.
It’s universal, so you can use it on non-kubernetes situations where other tools leave you high and dry.
* https://github.com/kapicorp/tesoro a secret “webhook controller” to seamlessly handle Kapitan secrets in your cluster. Better than sealed-secrets because there is no need to convert secrets and it supports KMS like google and aws together.
Get started with our blog: https://medium.com/kapitan-blog or join our kubernetes slack on #kapitan
It is. But k8s has no convenient way of parameterizing releases that can beat Helm. A simple stateless application needs:
- a deployment
- a service
- an ingress
- a config map (or several)
- a secret (or several)
It's even worse for stateful applications.
And each of the resource definitions is 60% boilerplate, 35% application-specific and 5% release- or environment-specific.
Helm would probably be a nice and neat tool if it had stopped at maintaining a simple map of variable names to values. But since applications need things like "if the user said SQLite, add a pvc, a configmap and a secret and refer to them in the ss, if she said Postgres, go pull another chart, deploy it with these parameters, then add this configmap and this secret and refer to them in the ss", Helm is an overcomplicated mess.
Sometimes I even wish they could embed a JavaScript interpreter... After all, YAML is almost equivalent to JSON, which the perfect templating language for JSON is -- JavaScript tbh.
Or people have to keep inventing half baked things.
When I started with kubernetes I converted my small Docker compose files to kubernetes files. Later I rewrote everything in helm charts. Now it's almost more YAML and golang templates lines than business logic lines in my applications.
I'm considering to go back to Docker compose files. It's simple, readable, and easy to maintain.