Helm tpl override issue in Flux

[anthony-pastor]

We are using FluxCD v0.11.0.

We are trying to deploy a Helm Chart using tpl overrides with Flux:

• This version is working: https://github.com/JordanGoasdoue/golang-demo-app-reproduce-flux-error
• This one is not: https://github.com/JordanGoasdoue/golang-demo-app-reproduce-flux-error/tree/non-working-version
  The error reported by Flux is:

flux -n jordan-golang-demo-app get hr
NAME                  	READY	MESSAGE                                                                                                                                                                                                                                          	REVISION	SUSPENDED 
jordan-golang-demo-app	False	Helm install failed: error while running post render on files: missing metadata.name in object {map[apiVersion:v1 kind:Service metadata:<nil> spec:map[ports:[map[port:80 protocol:TCP targetPort:8080]] selector:map[service:golang-demo-app]]]}

PS: Both charts are working with a manual Helm install/upgrade command:

helm upgrade --wait --install test-golang-demo-app -n reproduce-golang-demo-app charts/golang-demo-app/ --create-namespace
Release "test-golang-demo-app" does not exist. Installing it now.
NAME: test-golang-demo-app
LAST DEPLOYED: Fri Apr  2 17:46:11 2021
NAMESPACE: reproduce-golang-demo-app
STATUS: deployed
REVISION: 1
TEST SUITE: None

[hiddeco]

Would be very useful to also have a copy of the HelmRelease at hand before debugging this any further.

[anthony-pastor]

@hiddeco This was the latest test of our helmrelease definition:

---
apiVersion: helm.toolkit.fluxcd.io/v2beta1
kind: HelmRelease
metadata:
  name: jordan-golang-demo-app
  namespace: jordan-golang-demo-app
spec:
  chart:
    spec:
      chart: charts/golang-demo-app
      sourceRef:
        namespace: flux-system
        kind: GitRepository
        name: jordan-golang-demo-app
  interval: 30s
  targetNamespace: jordan-golang-demo-app
  releaseName: jordan-golang-demo-app

[hiddeco]

I do not see a createNamespace: true in the spec there, while you run the helm install with --create-namespace. (But the namespace already exists, as the HelmRelease is placed in the same directory).

Can you try downgrading to 0.8.2 and see if that solves the issue? If so, fluxcd/helm-controller#238 likely is the cause.

[stefanprodan]

@hiddeco based on kind:Service metadata:<nil> I guess the chart generates an invalid Kubernetes object. Maybe Helm renders this https://github.com/JordanGoasdoue/golang-demo-app-reproduce-flux-error/blob/main/charts/golang-demo-app/templates/svc.yaml#L12-L17 after post-render?

[hiddeco]

That should be impossible, as Helm first renders the resources as it would normally, and then calls the post-render, see:

https://github.com/helm/helm/blob/c9fe3d118caec699eb2565df9838673af379ce12/pkg/action/install.go#L240
https://github.com/helm/helm/blob/c9fe3d118caec699eb2565df9838673af379ce12/pkg/action/action.go#L105
https://github.com/helm/helm/blob/c9fe3d118caec699eb2565df9838673af379ce12/pkg/action/action.go#L219

It should thus not make any modifications afterwards, and it looks like Helm itself fails to produce a valid manifest.

[JordanGoasdoue]

Hello guys,

Thanks for the answers.

Just to be sure we are all on same input:

In fluxcd v2:
Looking at the svc.yaml (but it's same for deployment.yaml)

• This version from main branch is working currently: https://github.com/JordanGoasdoue/golang-demo-app-reproduce-flux-error/blob/main/charts/golang-demo-app/templates/svc.yaml#L12-L17

• This version from non-working-version branch isn't working: https://github.com/JordanGoasdoue/golang-demo-app-reproduce-flux-error/blob/non-working-version/charts/golang-demo-app/templates/svc.yaml#L14
  ( with the metadata from this centralized metadata file: https://github.com/JordanGoasdoue/golang-demo-app-reproduce-flux-error/blob/non-working-version/charts/golang-demo-app/templates/_metadata.yaml#L7-L9 )

The error is like if from Fluxcd it's not possible to take as default the values from https://github.com/JordanGoasdoue/golang-demo-app-reproduce-flux-error/blob/non-working-version/charts/golang-demo-app/templates/_metadata.yaml

With both these version, it's working with helm, and on the template or install we have the right values

We tried with already created namespaces, but we will try to rollback and see what happen 👌

[anthony-pastor]

@hiddeco we tried the same thing with a Flux 0.8.2 bootstraped cluster and we got the same issue:
jordan-golang-demo-app False Helm install failed: error while running post render on files: missing metadata.name in object {map[apiVersion:v1 kind:Service metadata:<nil> spec:map[ports:[map[port:80 protocol:TCP targetPort:8080]] selector:map[service:golang-demo-app]]]} False

[hiddeco]

Using Helm v3.5.3 I get the following error for the chart source:

$ helm version
version.BuildInfo{Version:"v3.5.3", GitCommit:"041ce5a2c17a58be0fcd5f5e16fb3e7e95fea622", GitTreeState:"dirty", GoVersion:"go1.16.2"}
$ helm install . --debug --dry-run --generate-name --namespace foo
install.go:173: [debug] Original chart version: ""
install.go:190: [debug] CHART PATH: /home/hidde/Projects/golang-demo-app-reproduce-flux-error/charts/golang-demo-app

Error: rendered manifests contain a resource that already exists. Unable to continue with install: could not get information about the resource: resource name may not be empty
helm.go:81: [debug] resource name may not be empty

I think the error is thus with the chart, and not with the helm-controller.

[anthony-pastor]

Very interesting @hiddeco, we observe the same behavior.

• Helm version 3.4.2: it still works to install the Chart.
• Helm version 3.5.3: it fails.
  Thanks, we will dig with Helm then.

[hiddeco]

Closing this, as it is essentially an upstream issue.