Lookup function not working

[mivalsten]

Output of helm version:

version.BuildInfo{Version:"v3.12.1", GitCommit:"f32a527a060157990e2aa86bf45010dfb3cc8b8d", GitTreeState:"clean", GoVersion:"go1.20.4"}

Output of kubectl version:

WARNING: This version information is deprecated and will be replaced with the output from kubectl version --short.  Use --output=yaml|json to get the full version.
Client Version: version.Info{Major:"1", Minor:"27", GitVersion:"v1.27.2", GitCommit:"7f6f68fdabc4df88cfea2dcf9a19b2b830f1e647", GitTreeState:"clean", BuildDate:"2023-05-17T14:20:07Z", GoVersion:"go1.20.4", Compiler:"gc", Platform:"windows/amd64"}
Kustomize Version: v5.0.1
Server Version: version.Info{Major:"1", Minor:"27", GitVersion:"v1.27.4", GitCommit:"fa3d7990104d7c1f16943a67f11b154b71f6a132", GitTreeState:"clean", BuildDate:"2023-07-21T14:07:10Z", GoVersion:"go1.20.6", Compiler:"gc", Platform:"linux/arm64"}

Cloud Provider/Platform (AKS, GKE, Minikube etc.):
Microk8s

Hi All!

For some reason, my lookup function does not work properly. Here is my chart:

_helpers.tpl

{{- define "password" -}}
{{- $len := 24 | int -}}
{{- $obj := (lookup "v1" "secret" .Namespace "gig3r-secret").data -}}
{{- if $obj }}
{{- index $obj "DB_PASSWORD" -}}
{{- else -}}
{{- randAlphaNum $len | b64enc -}}
{{- end -}}
{{- end }}

secrets.yaml

---
apiVersion: v1
kind: Secret
metadata:
  name: gig3r-secret
type: Opaque
data:
  DB_PASSWORD: "{{ include "gig3r.database.password" (dict "Namespace" .Release.Namespace ) }}"
  debug: "{{ (lookup "v1" "Secret" .Release.Namespace "gig3r-secret") | toJson }}"

kubectl get secret gig3r-secret -n test returns:

NAME           TYPE     DATA   AGE
gig3r-secret   Opaque   1      21h

I deploy this with below command: (sorry for windows escapes)

helm upgrade --install `
  gig3r-test `
  ../chart/gig3r `
  --wait `
  --atomic `
  --namespace=test `
  --create-namespace `
  --dry-run --debug

And the result is this:

MANIFEST:
---
# Source: gig3r/templates/secrets.yaml
apiVersion: v1
kind: Secret
metadata:
  name: gig3r-secret
type: Opaque
data:
  DB_PASSWORD: "SGRMWEZ4RlZCeGdublY1Y0xsaDE3VjUw"
  debug: "{}"

Every time I run, DB_PASSWORD is different, even though there is a secret/gig3r-secret in namespace test with key DB_PASSWORD. And as you can see from data.debug, lookup returns empty object. Is this a bug or am I doing something wrong?

[Ithrael]

helm upgrade --install `
  gig3r-test `
  ../chart/gig3r `
  --wait `
  --atomic `
  --namespace=test `
  --create-namespace `
  --dry-run --debug

remove dry-run
https://helm.sh/docs/chart_template_guide/functions_and_pipelines/

[mivalsten]

@Ithrael thank you, it works. I based my assumption that lookup should work with --dry-run on this entry.

What is then the difference between helm template and helm install --dry-run?

[Ithrael]

I believe they are essentially the same, because helm template will invoke the runInstall function , which is the core function in the helm install process. Then helm template will set dry-run value to true before invoking runInstall.

[lindhe]

Works with helm template --dry-run=server, though!

[Kerry-G]

helm upgrade --install `
  gig3r-test `
  ../chart/gig3r `
  --wait `
  --atomic `
  --namespace=test `
  --create-namespace `
  --dry-run --debug

remove dry-run https://helm.sh/docs/chart_template_guide/functions_and_pipelines/

This documentation is not true anymore, so I created a PR on the helm doc's repo.

[gjenkins8]

Thanks @Kerry-G (docs update looks to have been missed from #9426 )

[github-actions]

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