document-haness/docs/keycloak-session-store/source/deploy/lab/k8s/bff-redis.yaml

# BFF (2 replicas) + Redis, for the B-layer experiments.
#
# The BFF is deployed FIRST WITHOUT any session store wiring. That is deliberate:
# B-0 asks what Spring Boot's autoconfiguration actually picks when nothing is
# configured, and the only honest way to answer is to look at a running instance
# that has been given nothing. Redis is deployed alongside but left unused until
# B-1 turns it on.
#
#   kubectl apply -f deploy/lab/k8s/bff-redis.yaml
#
# Image comes from the workstation, not a registry:
#   docker build -t keycloak-pattern-bff:lab bff/
#   docker save keycloak-pattern-bff:lab | ssh test-server "ssh kc-lab-1 'sudo k3s ctr images import -'"
#   (repeat for kc-lab-2)
# so imagePullPolicy must stay Never on both replicas.
apiVersion: v1
kind: Secret
metadata:
  name: bff-secrets
  namespace: keycloak-lab
type: Opaque
stringData:
  # Matches the client created with kcadm in the keycloak-patterns realm.
  # Base64 in etcd is not encryption — see D-3.
  KEYCLOAK_CLIENT_SECRET: bff-lab-secret
---
# Redis. B-5 measured that turning on AOF with `redis-cli config set` changes
# nothing here, because /data is the container filesystem and dies with the
# container — the appendonlydir was created and then thrown away. Persistence
# configuration without a volume is decoration.
#
# So the volume comes first, and only then does `--appendonly yes` mean anything.
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: redis-data
  namespace: keycloak-lab
spec:
  accessModes: [ReadWriteOnce]
  storageClassName: local-path
  resources:
    requests:
      storage: 1Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: redis
  namespace: keycloak-lab
spec:
  replicas: 1
  selector:
    matchLabels: { app: redis }
  template:
    metadata:
      labels: { app: redis }
    spec:
      # Same node as postgres so a node-loss experiment takes both stores at
      # once, matching how A-4 was set up.
      nodeSelector:
        kubernetes.io/hostname: kc-lab-2
      containers:
        - name: redis
          image: redis:7.4-alpine
          # appendfsync everysec 이 기본값이다 — 1초 분량을 잃을 수 있다.
          # Keycloak 의 synchronous_commit OFF(A-3)와 같은 모양의 트레이드오프다.
          args: ["redis-server", "--appendonly", "yes", "--dir", "/data"]
          ports:
            - containerPort: 6379
              name: redis
          readinessProbe:
            exec: { command: ["redis-cli", "ping"] }
            initialDelaySeconds: 3
          volumeMounts:
            - name: data
              mountPath: /data
          resources:
            requests: { memory: 32Mi, cpu: 20m }
            limits:   { memory: 128Mi }
      volumes:
        - name: data
          persistentVolumeClaim:
            claimName: redis-data
---
apiVersion: v1
kind: Service
metadata:
  name: redis
  namespace: keycloak-lab
spec:
  selector: { app: redis }
  ports:
    - port: 6379
      targetPort: redis
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: bff
  namespace: keycloak-lab
spec:
  # Two replicas is the whole point: Q1 and Q2 only exist because a request can
  # land on an instance that did not handle the login.
  replicas: 2
  selector:
    matchLabels: { app: bff }
  template:
    metadata:
      labels: { app: bff }
    spec:
      # Spread across both nodes so "the other instance" is genuinely another
      # machine, not another process on the same kernel.
      topologySpreadConstraints:
        - maxSkew: 1
          topologyKey: kubernetes.io/hostname
          whenUnsatisfiable: ScheduleAnyway
          labelSelector:
            matchLabels: { app: bff }
      # 쿠버네티스는 같은 네임스페이스의 Service 마다 Docker link 시절의
      # 환경변수를 자동 주입한다: REDIS_PORT=tcp://10.43.57.116:6379.
      # 그것이 application.yml 의 ${REDIS_PORT:6379} 를 덮어써서 기동이 실패했다.
      #   Failed to bind properties under 'spring.data.redis.port' to int:
      #     Value: "tcp://10.43.57.116:6379"
      # 이 주입 자체를 끄는 것이 근본 처방이다. 이름을 바꿔 피하면 다음 사람이
      # 같은 함정에 다시 빠진다.
      enableServiceLinks: false
      containers:
        - name: bff
          image: keycloak-pattern-bff:lab
          imagePullPolicy: Never
          ports:
            - containerPort: 8083
              name: http
          env:
            # The browser is redirected to the public name; the BFF calls the
            # token endpoint over the cluster network. Getting these two the same
            # way round is what the 2-hop header experiment was about.
            - name: KC_ISSUER_EXTERNAL
              value: https://auth.hyeonworks.com/realms/keycloak-patterns
            - name: KC_ISSUER_INTERNAL
              value: http://keycloak.keycloak-lab.svc:8080/realms/keycloak-patterns
            # echo 는 header-lab 네임스페이스의 8081 이다. 다른 네임스페이스의
            # 서비스는 <svc>.<ns>.svc 로 부른다. 이름을 틀리면 500 이 나는데
            # 원인은 UnresolvedAddressException 이지 토큰 문제가 아니다.
            - name: RESOURCE_API_BASE_URL
              value: http://echo.header-lab.svc:8081
            - name: KEYCLOAK_CLIENT_SECRET
              valueFrom:
                secretKeyRef: { name: bff-secrets, key: KEYCLOAK_CLIENT_SECRET }
            # Spring needs to know it is behind TLS termination, for the same
            # reason Keycloak needs KC_PROXY_HEADERS. Without it the redirect_uri
            # it builds comes back as http:// and Keycloak rejects it.
            - name: SERVER_FORWARD_HEADERS_STRATEGY
              value: native
            # B-1: Application Session 을 Redis 로 옮긴다.
            # OAuth2AuthorizedClient 는 이것으로 옮겨지지 않는다 — 조회 키가
            # 다르기 때문이며, B-0 에서 확인한 사실이다.
            - name: SPRING_SESSION_STORE_TYPE
              value: redis
            - name: REDIS_HOST
              value: redis.keycloak-lab.svc
            - name: REDIS_PORT
              value: "6379"
            # B-2: authorized client 는 PostgreSQL 로. 세션(Redis)과 다른
            # 저장소를 쓰는 것이 Q3 가 말한 "각각 설계한다"의 실물이다.
            - name: BFF_DB_URL
              value: jdbc:postgresql://postgres.keycloak-lab.svc:5432/keycloak
            - name: BFF_DB_USER
              value: keycloak
            - name: BFF_DB_PASSWORD
              valueFrom:
                secretKeyRef: { name: keycloak-lab-secrets, key: POSTGRES_PASSWORD }
            - name: JAVA_TOOL_OPTIONS
              value: "-Xms128m -Xmx320m"
          readinessProbe:
            httpGet: { path: /actuator/health/readiness, port: http }
            initialDelaySeconds: 20
            failureThreshold: 30
          livenessProbe:
            httpGet: { path: /actuator/health/liveness, port: http }
            initialDelaySeconds: 60
          resources:
            requests: { memory: 320Mi, cpu: 100m }
            limits:   { memory: 512Mi }
---
apiVersion: v1
kind: Service
metadata:
  name: bff
  namespace: keycloak-lab
spec:
  selector: { app: bff }
  ports:
    - port: 8083
      targetPort: http
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: bff
  namespace: keycloak-lab
spec:
  ingressClassName: traefik
  rules:
    - host: app1.hyeonworks.com
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: bff
                port:
                  number: 8083