gitops-workflow

SKILL.md

GitOps Workflow

Complete guide to implementing GitOps workflows with ArgoCD and Flux for automated Kubernetes deployments.

Purpose

Implement declarative, Git-based continuous delivery for Kubernetes using ArgoCD or Flux CD, following OpenGitOps principles.

When to Use This Skill

Set up GitOps for Kubernetes clusters

Automate application deployments from Git

Implement progressive delivery strategies

Manage multi-cluster deployments

Configure automated sync policies

Set up secret management in GitOps

OpenGitOps Principles

Declarative - Entire system described declaratively

Versioned and Immutable - Desired state stored in Git

Pulled Automatically - Software agents pull desired state

Continuously Reconciled - Agents reconcile actual vs desired state

ArgoCD Setup

1. Installation

# Create namespace
kubectl create namespace argocd

# Install ArgoCD
kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml

# Get admin password
kubectl -n argocd get secret argocd-initial-admin-secret -o jsonpath="{.data.password}" | base64 -d

Reference: See references/argocd-setup.md for detailed setup

2. Repository Structure

gitops-repo/
├── apps/
│   ├── production/
│   │   ├── app1/
│   │   │   ├── kustomization.yaml
│   │   │   └── deployment.yaml
│   │   └── app2/
│   └── staging/
├── infrastructure/
│   ├── ingress-nginx/
│   ├── cert-manager/
│   └── monitoring/
└── argocd/
    ├── applications/
    └── projects/

3. Create Application

# argocd/applications/my-app.yaml
apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: my-app
  namespace: argocd
spec:
  project: default
  source:
    repoURL: https://github.com/org/gitops-repo
    targetRevision: main
    path: apps/production/my-app
  destination:
    server: https://kubernetes.default.svc
    namespace: production
  syncPolicy:
    automated:
      prune: true
      selfHeal: true
    syncOptions:
      - CreateNamespace=true

4. App of Apps Pattern

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: applications
  namespace: argocd
spec:
  project: default
  source:
    repoURL: https://github.com/org/gitops-repo
    targetRevision: main
    path: argocd/applications
  destination:
    server: https://kubernetes.default.svc
    namespace: argocd
  syncPolicy:
    automated: {}

Flux CD Setup

1. Installation

# Install Flux CLI
curl -s https://fluxcd.io/install.sh | sudo bash

# Bootstrap Flux
flux bootstrap github \
  --owner=org \
  --repository=gitops-repo \
  --branch=main \
  --path=clusters/production \
  --personal

2. Create GitRepository

apiVersion: source.toolkit.fluxcd.io/v1
kind: GitRepository
metadata:
  name: my-app
  namespace: flux-system
spec:
  interval: 1m
  url: https://github.com/org/my-app
  ref:
    branch: main

3. Create Kustomization

apiVersion: kustomize.toolkit.fluxcd.io/v1
kind: Kustomization
metadata:
  name: my-app
  namespace: flux-system
spec:
  interval: 5m
  path: ./deploy
  prune: true
  sourceRef:
    kind: GitRepository
    name: my-app

Sync Policies

Auto-Sync Configuration

ArgoCD:

syncPolicy:
  automated:
    prune: true # Delete resources not in Git
    selfHeal: true # Reconcile manual changes
    allowEmpty: false
  retry:
    limit: 5
    backoff:
      duration: 5s
      factor: 2
      maxDuration: 3m

Flux:

spec:
  interval: 1m
  prune: true
  wait: true
  timeout: 5m

Reference: See references/sync-policies.md

Progressive Delivery

Canary Deployment with ArgoCD Rollouts

apiVersion: argoproj.io/v1alpha1
kind: Rollout
metadata:
  name: my-app
spec:
  replicas: 5
  strategy:
    canary:
      steps:
        - setWeight: 20
        - pause: { duration: 1m }
        - setWeight: 50
        - pause: { duration: 2m }
        - setWeight: 100

Blue-Green Deployment

strategy:
  blueGreen:
    activeService: my-app
    previewService: my-app-preview
    autoPromotionEnabled: false

Secret Management

External Secrets Operator

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: db-credentials
spec:
  refreshInterval: 1h
  secretStoreRef:
    name: aws-secrets-manager
    kind: SecretStore
  target:
    name: db-credentials
  data:
    - secretKey: password
      remoteRef:
        key: prod/db/password

Sealed Secrets

# Encrypt secret
kubeseal --format yaml < secret.yaml > sealed-secret.yaml

# Commit sealed-secret.yaml to Git

Best Practices

Use separate repos or branches for different environments

Implement RBAC for Git repositories

Enable notifications for sync failures

Use health checks for custom resources

Implement approval gates for production

Keep secrets out of Git (use External Secrets)

Use App of Apps pattern for organization

Tag releases for easy rollback

Monitor sync status with alerts

Test changes in staging first

Troubleshooting

Sync failures:

argocd app get my-app
argocd app sync my-app --prune

Out of sync status:

argocd app diff my-app
argocd app sync my-app --force

Related Skills

k8s-manifest-generator - For creating manifests

helm-chart-scaffolding - For packaging applications