"Cross-Resource DependsOn"

[unbis]

Hello,

Currently I'm exploring the new Flux a bit and wanted to setup cert-manager and a cluster-issuer in my test-cluster. For this I decided to use the official Helm template (seeing as the static "vanilla" YAML for each release is generated from this by now). The cluster-issuer was supposed to be a simple Kustomization. I realised, however, that dependsOn only allows me to specify a resource of its own type, i.e. a HelmRelease can only depend on a HelmRelease.

Now to my question, is there a way around this or is it just bad practice to mix two "release-types"?

[kingdonb]

DependsOn cannot be cross-resource and this will not be possible, a cross-resource dependency is contraindicated and would not fit with the design, a Kustomization can only depend on another Kustomization. However, this does not mean your use case is impossible.

A HelmRelease is a custom resource that is first applied by a Kustomization. Any kustomization can absolutely perform health assessments on any custom resources that are created by it, as long as these custom resources report their own status as HelmRelease does. You can make a Kustomization that does not report as ready until after a HelmRelease is ready (cert-manager) and another Kustomization that depends on it. So a second kustomization creating your cluster-issuer will apply only when the cert-manager release installed and became ready. It is not a Cross-Resource DependsOn, but I think it has the properties you're expecting.

[squaremo]

"intermediate" Kustomization to achieve my goal.

Wonder if anyone would care to share an example of how this is done?

I explain the workaround in my comment #730 (reply in thread).

[artem-nefedov]

Here are some very common examples where that would be useful:

• Application from Helm chart using a SOPS-encrypted Secret (which must be deployed from Kustomization, because you don't want to store unencrypted secrets in any object other than Secret).
• Helm chart deploying to a namespace created by Kustomization.

[SimonStiil]

This would be awesome if it was explained as part of the documentation of "depends on" for Kustomization.
I was looking up the depends on for both Kustomization and HelmRelease as I have a flow that:

1. Install CRD + secrets through Kustomization
2. Install Helm chart for an opperator
3. Install Custom Resources through Kustomization

A flow I'm guessing is quite normal.
But reading this it makes sense to just have 3 Kustomization that depends on and not think of depends on on the Helm side.
Which is logical when you think of how the HelmRelease are read. But when designing it it was not as logical.

[webermaster]

I am trying to implement a version of this dependency right now. I'm struggling, an example repo would be helpful.

[kingdonb]

The repo https://github.com/fluxcd/flux2-kustomize-helm-example is implemented with several examples, see the production cluster which has apps and infrastructure with several inter-dependencies, to put CRDs in order before controllers before applications that depend on the CRD service. Hope this helps!