charts/vertical-pod-autoscaler: Extract common probe configurations to template helpers

[jparavisini]

Summary

Improve maintainability of the vertical-pod-autoscaler chart by extracting repeated probe configurations into _helpers.tpl.

Background

Following the code review of PR #250, the vertical-pod-autoscaler chart has repeated probe configurations across all three components (recommender, updater, admission-controller). Each component uses similar liveness and readiness probe structures.

Proposed Changes

1. Create template helpers in _helpers.tpl for:

   • Common liveness probe configuration
   • Common readiness probe configuration
   • Allow customization through values while maintaining DRY principles

2. Update all component templates to use the new helpers:

   • charts/vertical-pod-autoscaler/templates/recommender.yaml
   • charts/vertical-pod-autoscaler/templates/updater.yaml
   • charts/vertical-pod-autoscaler/templates/admission-controller.yaml

Benefits

• Reduces code duplication
• Easier maintenance when updating probe configurations
• Consistent probe behavior across all VPA components
• Follows Helm best practices for template organization

Example Helper Structure

{{- define "vertical-pod-autoscaler.livenessProbe" -}}
httpGet:
  path: /health-check
  port: metrics
  scheme: HTTP
failureThreshold: {{ .Values.livenessProbe.failureThreshold | default 6 }}
periodSeconds: {{ .Values.livenessProbe.periodSeconds | default 5 }}
successThreshold: {{ .Values.livenessProbe.successThreshold | default 1 }}
timeoutSeconds: {{ .Values.livenessProbe.timeoutSeconds | default 3 }}
{{- end }}

Labels

• enhancement
• vertical-pod-autoscaler
• maintainability