[helm] reload chart for each example folder

[pkoutsovasilis]

What does this PR do?

This PR fixes an issue with the Helm chart examples rendering. Specifically, the Helm chart is now reloaded for each example folder. Previously, the chart was loaded once and reused, which leads to stale data when different examples enable or disable subchart dependencies (spoiler alert for the upcoming kube-state-metrics subchart dependency PR I am working on).

Why is it important?

Reloading the Helm chart for each example folder ensures correctness in the rendered k8s manifests.

Checklist

• I have read and understood the pull request guidelines of this project.
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool
• I have added an integration test or an E2E test

Disruptive User Impact

How to test this PR locally

mage helm:renderExamples

Related issues

N/A

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[elastic-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarQube

[swiatekm]

Does running init mean that we do a dependency pull on each invocation?

Previously, the chart was loaded once and reused, which leads to stale data when different examples enable or disable subchart dependencies (spoiler alert for the upcoming kube-state-metrics subchart dependency PR I am working on).

Does this also happen if the dependency is controlled via a condition in the values file?

[pkoutsovasilis]

Thank you for the question @swiatekm 🙂

Does running init mean that we do a dependency pull on each invocation?

There is no dependency pull while loading the Helm chart from a path (helmChart, err := loader.Load(helmChartPath)). You must explicitly run helm dependency build ./chart_path before you can install the chart from a disk path

Does this also happen if the dependency is controlled via a condition in the values file?

My observation is that using the same helmChart from helmChart, err := loader.Load(helmChartPath) for each example sometimes resulted in the subchart not being rendered. My suspicion is that this happens because a previous example folder might have explicitly disabled that subchart by setting the condition in the values file to false, and the chart is reused without re-initializing its dependencies correctly?!.

I hope this helps clarify the behaviour I have observed, let me know if you have further questions.

[swiatekm]

I don't think this change has any negative side effects, but it feels like we're working around a bug in Helm.