flux-gitops

Flux GitOps Platform

The homelab Kubernetes platform uses Flux ResourceSets for centralized, declarative management of Helm releases and configurations.

Platform Files Overview

Adding a New Helm Release

Step 1: Add to helm-charts.yaml

Add an entry to the inputs array:

inputs:
  - name: "my-new-chart"           # Unique release name (kebab-case)
    namespace: "my-namespace"       # Target namespace
    chart:
      name: "actual-chart-name"    # Chart name in repository
      version: "1.0.0"             # Pinned version
      url: "https://example.com/charts"  # Helm repository URL
    dependsOn: [cilium]            # Array of release names this depends on

For OCI registries:

    chart:
      name: "app-template"
      version: "3.6.1"
      url: "oci://ghcr.io/bjw-s/helm"  # Prefix with oci://

Step 2: Create Values File

Create charts/<release-name>.yaml with Helm values:

# yaml-language-server: $schema=<chart-schema-url>
---
# Helm values for the chart
replicas: 1
image:
  repository: myapp
  tag: v1.0.0

Step 3: Add to kustomization.yaml

Add the values file to the configMapGenerator:

configMapGenerator:
  - name: platform-values
    files:
      # ... existing entries
      - charts/my-new-chart.yaml

Step 4: Add Config Resources (Optional)

If the chart needs additional resources (secrets, configs), add to config/:

config/my-new-chart/
├── kustomization.yaml
├── secret.yaml
└── config.yaml

Then reference in config.yaml ResourceSet.

ResourceSet Template Syntax

The resourcesTemplate uses Go text/template with << >> delimiters:

resourcesTemplate: |
  apiVersion: helm.toolkit.fluxcd.io/v2
  kind: HelmRelease
  metadata:
    name: << inputs.name >>
    namespace: << inputs.provider.namespace >>
  spec:
    <<- if inputs.dependsOn >>
    dependsOn:
    <<- range $dep := inputs.dependsOn >>
      - name: << $dep >>
    <<- end >>
    <<- end >>
    chart:
      spec:
        chart: << inputs.chart.name >>
        version: << inputs.chart.version >>

Template Functions

• << inputs.field >> - Access input field
• <<- if condition >> - Conditional (with - to trim whitespace)
• <<- range $item := inputs.array >> - Loop over array
• hasPrefix "oci://" inputs.chart.url - String prefix check

Variable Substitution

Flux substitutes variables from the flux-system ConfigMap:

# In values file
ingress:
  hosts:
    - host: grafana.${internal_domain}  # Substituted at reconciliation

# Available variables
${cluster_name}      # dev, integration, live
${cluster_id}        # Numeric cluster ID
${internal_domain}   # internal.dev.tomnowak.work
${external_domain}   # External domain

Dependency Management

Release Dependencies

inputs:
  - name: "grafana"
    dependsOn: [kube-prometheus-stack, promtail]  # Waits for these

ResourceSet Dependencies

spec:
  dependsOn:
    - apiVersion: fluxcd.controlplane.io/v1
      kind: ResourceSet
      name: platform-namespaces  # Waits for namespaces ResourceSet

Debugging Flux

Check ResourceSet Status

kubectl get resourcesets -n flux-system
kubectl describe resourceset platform-resources -n flux-system

Check HelmRelease Status

kubectl get helmreleases -A
kubectl describe helmrelease <name> -n <namespace>

Check Reconciliation Logs

kubectl logs -n flux-system deploy/flux-controller -f | grep <release-name>

Force Reconciliation

flux reconcile helmrelease <name> -n <namespace>
flux reconcile kustomization flux-system -n flux-system

Common Issues

Best Practices

1. Pin versions: Always specify exact chart versions
2. Declare dependencies: Use dependsOn to ensure ordering
3. Use substitution: Never hardcode domains or cluster names
4. Values per release: One values file per HelmRelease
5. Minimal values: Only override what you need to change

OCI Registry Specifics

When using OCI registries like GHCR:

chart:
  name: "app-template"           # Just the chart name
  version: "3.6.1"
  url: "oci://ghcr.io/bjw-s/helm"  # Registry URL with oci:// prefix

The ResourceSet template automatically detects OCI URLs and sets type: oci on the HelmRepository.