Imported from jawsbaek/scp-gitops-sample (gitops-control-plane/apps/AGENTS.md). Install upstream with npx skills add jawsbaek/scp-gitops-sample --skill apps. Copyright stays with the author.

gitops-control-plane/apps/ — App-of-Apps 및 ApplicationSet

Argo CD App-of-Apps 패턴의 핵심으로 모든 인프라, 서비스, 애플리케이션 Application을 자동 생성합니다.

Purpose

• 계층적 관리: 루트 → 중간 ApplicationSet → 개별 Application
• 자동 감지: Git 디렉토리 변경 → Application 자동 생성/삭제
• 환경별 동기화: dev/staging 자동, prod 수동 승인
• 단일 진입점: app-of-apps만 적용하면 전체 시스템 관리

Key Files

For AI Agents

Working In This Directory

ApplicationSet 자동 감지 원리

# 1. 인프라 ApplicationSet → environments/{env}/infra 스캔
#    - environments/dev/infra 존재 → dev-infra Application 생성
#    - environments/staging/infra 존재 → staging-infra Application 생성

# 2. 서비스 ApplicationSet → cluster-services/* 스캔
#    - cluster-services/argocd 존재 → svc-argocd Application 생성
#    - cluster-services/cert-manager 존재 → svc-cert-manager Application 생성

# 3. 앱 ApplicationSet → app-manifests/overlays/{env}/{app} 스캔
#    - app-manifests/overlays/dev/itop → dev-itop Application 생성
#    - app-manifests/overlays/prod/itop → prod-itop Application 생성

ApplicationSet 상태 확인

# ApplicationSet 목록
kubectl get applicationset -n argocd

# 생성된 Application 확인
argocd app list | grep -E "^(dev|staging|prod|svc)-"

# ApplicationSet 상세 정보
kubectl describe applicationset services-applicationset -n argocd

새 Application 추가 절차

1. 인프라 추가 (환경별)

# environments/dev/infra/ 디렉토리 생성
mkdir -p environments/dev/infra
# → applicationset-infra가 자동으로 dev-infra Application 생성

2. 클러스터 서비스 추가

# cluster-services/{service-name}/ 디렉토리 생성
mkdir -p cluster-services/{service-name}
# → applicationset-services가 자동으로 svc-{service-name} Application 생성

3. 비즈니스 앱 추가

# app-manifests/overlays/{env}/{app}/ 디렉토리 생성
mkdir -p app-manifests/overlays/dev/{app-name}
# → applicationset-apps가 자동으로 dev-{app-name} Application 생성

Common Patterns

루트 Application (app-of-apps.yaml)

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: app-of-apps
  namespace: argocd
  annotations:
    argocd.argoproj.io/sync-wave: "-10"  # 가장 먼저 동기화
spec:
  project: default
  source:
    repoURL: https://gitlab.scp.internal/gitops/scp-gitops-gemini.git
    targetRevision: main
    path: gitops-control-plane/apps
  destination:
    server: https://kubernetes.default.svc
    namespace: argocd
  syncPolicy:
    automated:
      prune: false      # ApplicationSet 삭제 방지
      selfHeal: true
    syncOptions:
      - CreateNamespace=true

인프라 ApplicationSet (Git Generator)

# applicationset-infra.yaml
apiVersion: argoproj.io/v1alpha1
kind: ApplicationSet
metadata:
  name: infra-applicationset
  namespace: argocd
spec:
  goTemplate: true
  generators:
    - git:
        repoURL: https://gitlab.scp.internal/gitops/scp-gitops-gemini.git
        revision: main
        directories:
          - path: environments/*/infra
  template:
    metadata:
      name: '{{ .path.basename }}-infra'
      annotations:
        argocd.argoproj.io/sync-wave: "-5"
    spec:
      project: infra
      source:
        repoURL: https://gitlab.scp.internal/gitops/scp-gitops-gemini.git
        targetRevision: main
        path: '{{ .path.path }}'
      destination:
        server: https://kubernetes.default.svc
      syncPolicy:
        automated:
          prune: true
          selfHeal: true

서비스 ApplicationSet (Sync Wave)

# applicationset-services.yaml
apiVersion: argoproj.io/v1alpha1
kind: ApplicationSet
metadata:
  name: services-applicationset
  namespace: argocd
spec:
  goTemplate: true
  generators:
    - git:
        repoURL: https://gitlab.scp.internal/gitops/scp-gitops-gemini.git
        revision: main
        directories:
          - path: cluster-services/*
  template:
    metadata:
      name: svc-{{ .path.basename }}
      annotations:
        # Sync Wave 자동 할당 (디렉토리명으로 결정)
        argocd.argoproj.io/sync-wave: |-
          {{- if has .path.basename (list "namespaces" "storage" "coredns") }}
          "-5"
          {{- else if eq .path.basename "cert-manager" }}
          "-3"
          {{- else if has .path.basename (list "openbao" "secrets" "external-secrets") }}
          "-2"
          {{- else if has .path.basename (list "istio-system" "service-mesh") }}
          "-1"
          {{- else if has .path.basename (list "argocd" "rbac") }}
          "0"
          {{- else if has .path.basename (list "monitoring" "logging") }}
          "1"
          {{- else if eq .path.basename "kyverno" }}
          "5"
          {{- else }}
          "10"
          {{- end }}
    spec:
      project: platform
      source:
        repoURL: https://gitlab.scp.internal/gitops/scp-gitops-gemini.git
        targetRevision: main
        path: '{{ .path.path }}'
      destination:
        server: https://kubernetes.default.svc
      syncPolicy:
        automated:
          prune: true
          selfHeal: true

앱 ApplicationSet (Matrix Generator)

# applicationset-apps.yaml
apiVersion: argoproj.io/v1alpha1
kind: ApplicationSet
metadata:
  name: apps-applicationset
  namespace: argocd
spec:
  goTemplate: true
  # 환경 및 앱 조합 생성
  generators:
    - matrix:
        generators:
          - git:
              repoURL: https://gitlab.scp.internal/gitops/scp-gitops-gemini.git
              revision: main
              directories:
                - path: app-manifests/overlays/dev/*
          - list:
              elements:
                - name: dev
                  cluster: ske-dev
                  syncAutomated: "true"
    # staging과 prod도 유사하게 정의
  template:
    metadata:
      name: '{{ .path.basename }}-{{ .name }}'
    spec:
      project: apps
      source:
        repoURL: https://gitlab.scp.internal/gitops/scp-gitops-gemini.git
        targetRevision: main
        path: '{{ .path.path }}'
      destination:
        server: '{{ .cluster }}'
      syncPolicy:
        automated:
          prune: '{{ .syncAutomated }}'
          selfHeal: true

Dependencies

Sync Wave 실행 순서

중요: ApplicationSet 생성 규칙을 정확히 따르면 Git 디렉토리 구조만으로 자동 Application 생성이 가능합니다.