[Bug]: Template Rendering Conflict in Helm Charts

[millaguie]

Contact Details

the same user as in github [at] icij [dot] org

What happened?

Description

In the way Helm manages the templating system, it might fail if two charts are being rendered simultaneously and those charts have a template with the same name but return different outputs. This issue is encountered when attempting to deploy a neo4j chart and its backup chart in the same deployment. This is a typical scenario when deploying using ArgoCD.

Reproduction Steps

Create a Chart.yaml file with the following content:

---
apiVersion: v2
name: my-app
version: 1.0.0
dependencies:
  - name: neo4j
    repository: https://helm.neo4j.com/neo4j
    version: 5.21.2
  - name: neo4j-admin
    repository: https://helm.neo4j.com/neo4j
    version: 5.21.2

Create a values.yaml file with the following content:

neo4j-admin:
  disableLookups: true
  nodeSelector:
    beta.kubernetes.io/arch: amd64
neo4j:
  disableLookups: true
  neo4j:
    name: "neo4j"
  volumes:
    data:
      mode: "dynamic"
      dynamic:
        storageClassName: default
        requests:
          storage: 10Gi
  nodeSelector:
    beta.kubernetes.io/arch: amd64

Run the following commands:

helm dependency build
helm template . --name-template my-app --namespace my-app --kube-version 1.29 --values values.yaml

Expected Behavior

Both charts should render correctly without conflicts.

Actual Behavior

The following error is encountered:

Error: template: my-app/charts/neo4j/templates/neo4j-statefulset.yaml:84:10: executing "my-app/charts/neo4j/templates/neo4j-statefulset.yaml" at <include "neo4j.nodeSelector" .Values.nodeSelector>: error calling include: template: my-app/charts/neo4j-admin/templates/_labels.tpl:18:41: executing "neo4j.nodeSelector" at <.Values.nodeSelector>: nil pointer evaluating interface {}.nodeSelector

Use --debug flag to render out invalid YAML

Environment

• Helm Version: v3.12.0 (also tested with v3.15.3, same result)
• Kubernetes Version: v1.29
• Helm Charts:
  • neo4j v5.21.2
  • neo4j-admin v5.21.2
• Deployment Tool: ArgoCD

Possible Solution

A potential solution is to change the name for the neo4j.nodeSelector in the admin chart to neo4j-admin.nodeSelector to avoid conflicts.

Note: The version of the chart I'm using is 5.21.2 but it is not in the list Note2: the code of conduct link points to https://example.com/ ....

Chart Name

Neo4j

Chart Version

5.12.0

Environment

Amazon Web Services

Relevant log output

Error: template: my-app/charts/neo4j/templates/neo4j-statefulset.yaml:84:10: executing "my-app/charts/neo4j/templates/neo4j-statefulset.yaml" at <include "neo4j.nodeSelector" .Values.nodeSelector>: error calling include: template: my-app/charts/neo4j-admin/templates/_labels.tpl:18:41: executing "neo4j.nodeSelector" at <.Values.nodeSelector>: nil pointer evaluating interface {}.nodeSelector

Use --debug flag to render out invalid YAML

Code of Conduct

• [X] I agree to follow this project's Code of Conduct

[ikwattro]

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