Docker Compose 不只是开发工具。在中小规模生产环境中，它同样能胜任。本文分享如何用 Compose 编排一个包含 6 个服务的完整应用栈，以及踩过的坑。

docker compose ps — 服务状态
caddy
:80 :443
~45MB
app-api
:3000
~280MB
app-worker
—
~190MB
postgres
:5432
~512MB
redis
:6379
~128MB
minio
:9000
~340MB

一、compose.yaml 编排

# compose.yaml — 生产环境
services:
  caddy:
    image: caddy:2-alpine
    ports: ["80:80", "443:443"]
    volumes:
      - ./Caddyfile:/etc/caddy/Caddyfile
      - caddy_data:/data
      - caddy_config:/config
    restart: unless-stopped
    networks: [frontend]

  app-api:
    build: { context: ., dockerfile: Dockerfile }
    command: node dist/server.js
    env_file: .env
    deploy:
      resources:
        limits: { memory: 512M, cpus: '1.0' }
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:3000/health"]
      interval: 30s
      timeout: 5s
      retries: 3
    depends_on:
      postgres: { condition: service_healthy }
      redis: { condition: service_healthy }
    networks: [frontend, backend]
    restart: unless-stopped

  postgres:
    image: postgres:16-alpine
    volumes: [pgdata:/var/lib/postgresql/data]
    environment:
      POSTGRES_DB: ${DB_NAME}
      POSTGRES_USER: ${DB_USER}
      POSTGRES_PASSWORD: ${DB_PASS}
    healthcheck:
      test: ["CMD", "pg_isready"]
    networks: [backend]
    restart: unless-stopped

  redis:
    image: redis:7-alpine
    command: redis-server --maxmemory 256mb --maxmemory-policy allkeys-lru
    volumes: [redis_data:/data]
    healthcheck:
      test: ["CMD", "redis-cli", "ping"]
    networks: [backend]
    restart: unless-stopped

volumes:
  caddy_data: { driver: local, driver_opts: { type: none, o: bind, device: /data/volumes/caddy_data } }
  pgdata: { driver: local, driver_opts: { type: none, o: bind, device: /data/volumes/pgdata } }
  redis_data: { driver: local, driver_opts: { type: none, o: bind, device: /data/volumes/redis_data } }

networks:
  frontend: { driver: bridge }
  backend: { driver: bridge }

二、关键实践

2.1 健康检查与启动顺序

Compose 的 depends_on 配合 condition: service_healthy，确保数据库完全就绪后才启动应用。这比 sleep 等待可靠得多。

2.2 资源限制

生产环境必须设置 deploy.resources.limits，防止一个容器 OOM 拖垮整个主机。

2.3 数据持久化

⚠️ 数据安全：永远使用 bind mount 而非 Docker volume 来存储数据库数据。这样即使 docker compose down 误操作，数据也不会丢失。同时记得定期备份。

三、日志管理

# docker-compose 日志配置
services:
  app-api:
    logging:
      driver: "json-file"
      options:
        max-size: "10m"
        max-file: "3"
        tag: "{{.Name}}"

配合 docker compose logs -f --tail=100 查看实时日志，生产环境用 Loki + Promtail 收集更佳。

四、备份脚本

#!/bin/bash
# backup.sh — 每日备份
BACKUP_DIR="/data/backups/$(date +%Y%m%d)"
mkdir -p $BACKUP_DIR

# PostgreSQL 备份
docker compose exec -T postgres pg_dump -U app myapp | gzip > $BACKUP_DIR/db.sql.gz

# Redis 备份
docker compose exec -T redis redis-cli BGSAVE
cp /data/volumes/redis_data/dump.rdb $BACKUP_DIR/

# 保留最近 7 天
find /data/backups -mtime +7 -exec rm -rf {} +

echo "Backup done: $BACKUP_DIR"

五、总结