GitOps on OpenShift with ArgoCD

GitOps is a modern approach to continuous delivery that uses Git as the single source of truth for declarative infrastructure and applications.

What is GitOps?

GitOps principles:

• Declarative: Everything is described in Git
• Versioned: Full history of changes
• Automated: Changes applied automatically
• Auditable: Who changed what and when

Installing ArgoCD on OpenShift

# Create namespace
oc new-project argocd

# Install ArgoCD operator from OperatorHub
oc apply -f - <<EOF
apiVersion: argoproj.io/v1alpha1
kind: ArgoCD
metadata:
  name: argocd
  namespace: argocd
spec:
  server:
    route:
      enabled: true
EOF

Creating an Application

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: my-app
  namespace: argocd
spec:
  project: default
  source:
    repoURL: https://github.com/org/my-app.git
    targetRevision: main
    path: k8s/overlays/production
  destination:
    server: https://kubernetes.default.svc
    namespace: production
  syncPolicy:
    automated:
      prune: true
      selfHeal: true

Directory Structure

my-app/
├── base/
│   ├── deployment.yaml
│   ├── service.yaml
│   └── kustomization.yaml
└── overlays/
    ├── development/
    │   └── kustomization.yaml
    └── production/
        └── kustomization.yaml

Benefits

1. Consistency: Same deployment process everywhere
2. Recovery: Easy rollback via Git revert
3. Security: No direct cluster access needed
4. Compliance: Full audit trail

Conclusion

GitOps with ArgoCD on OpenShift provides a robust, auditable, and automated deployment pipeline. Embrace the GitOps model to improve your delivery velocity and reliability.