GitOps와 ArgoCD로 쿠버네티스 배포 완전 자동화하기

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

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

gitops-repo/
├── apps/
│   └── my-app/
│       ├── base/
│       │   ├── deployment.yaml
│       │   └── kustomization.yaml
│       └── overlays/
│           ├── staging/
│           └── prod/
└── argocd/
    └── applications/

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: my-app-prod
  namespace: argocd
spec:
  source:
    repoURL: https://github.com/my-org/gitops-repo
    targetRevision: main
    path: apps/my-app/overlays/prod
  destination:
    server: https://kubernetes.default.svc
    namespace: production
  syncPolicy:
    automated:
      prune: true      # Git에서 삭제된 리소스 자동 제거
      selfHeal: true   # 클러스터 직접 변경 시 자동 복원

# overlays/prod/kustomization.yaml
resources:
- ../../base

images:
- name: my-app
  newTag: v1.2.3

patches:
- path: patch-replicas.yaml

- name: Update GitOps Repo
  run: |
    git clone https://github.com/my-org/gitops-repo
    cd gitops-repo/apps/my-app/overlays/prod
    kustomize edit set image my-app=my-registry/my-app:${{ github.sha }}
    git add -A
    git commit -m "chore: update to ${{ github.sha }}"
    git push