docker-compose.yml

# Smart City Traffic Analytics — docker-compose
# Run: docker compose up --build
# Stop: docker compose down
# Wipe data: docker compose down -v

services:

  # ── MongoDB ──────────────────────────────────────────────────────────────
  mongodb:
    image: mongo:7.0
    container_name: traffic_mongodb
    restart: unless-stopped
    ports:
      - "27017:27017"
    volumes:
      - mongodb_data:/data/db
    healthcheck:
      test: ["CMD", "mongosh", "--quiet", "--eval", "db.adminCommand('ping').ok"]
      interval: 10s
      timeout: 5s
      retries: 10
      start_period: 20s

  # ── MySQL ─────────────────────────────────────────────────────────────────
  mysql:
    image: mysql:8.0
    container_name: traffic_mysql
    restart: unless-stopped
    ports:
      - "3306:3306"
    environment:
      MYSQL_ROOT_PASSWORD: rootpassword
      MYSQL_DATABASE: traffic_db
      # Extra user kept for future use; Flask connects as root
      MYSQL_USER: traffic_user
      MYSQL_PASSWORD: traffic_pass
    volumes:
      - mysql_data:/var/lib/mysql
    # BUG FIX: use mysqladmin ping which is reliable even during init
    healthcheck:
      test: ["CMD", "mysqladmin", "ping", "-h", "127.0.0.1",
             "-u", "root", "--password=rootpassword", "--silent"]
      interval: 10s
      timeout: 5s
      retries: 12
      start_period: 30s

  # ── Zookeeper (needed by Kafka) ────────────────────────────────────────────
  zookeeper:
    image: confluentinc/cp-zookeeper:7.5.0
    container_name: traffic_zookeeper
    restart: unless-stopped
    ports:
      - "2181:2181"
    environment:
      ZOOKEEPER_CLIENT_PORT: 2181
      ZOOKEEPER_TICK_TIME: 2000
    healthcheck:
      test: ["CMD-SHELL", "echo ruok | nc -w 2 127.0.0.1 2181 | grep -q imok"]
      interval: 10s
      timeout: 5s
      retries: 8
      start_period: 15s

  # ── Kafka ─────────────────────────────────────────────────────────────────
  kafka:
    image: confluentinc/cp-kafka:7.5.0
    container_name: traffic_kafka
    restart: unless-stopped
    ports:
      - "9092:9092"   # external (host → container)
    environment:
      # BUG FIX: two separate listeners so internal services use kafka:29092
      # and the host machine can reach localhost:9092 for the simulator.
      KAFKA_ZOOKEEPER_CONNECT:                  zookeeper:2181
      KAFKA_LISTENER_SECURITY_PROTOCOL_MAP:     INTERNAL:PLAINTEXT,EXTERNAL:PLAINTEXT
      KAFKA_LISTENERS:                          INTERNAL://0.0.0.0:29092,EXTERNAL://0.0.0.0:9092
      KAFKA_ADVERTISED_LISTENERS:               INTERNAL://kafka:29092,EXTERNAL://localhost:9092
      KAFKA_INTER_BROKER_LISTENER_NAME:         INTERNAL
      KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR:   1
      KAFKA_TRANSACTION_STATE_LOG_REPLICATION_FACTOR: 1
      KAFKA_TRANSACTION_STATE_LOG_MIN_ISR:      1
      KAFKA_AUTO_CREATE_TOPICS_ENABLE:          "true"
      KAFKA_LOG_RETENTION_HOURS:               24
    depends_on:
      zookeeper:
        condition: service_healthy
    healthcheck:
      test: ["CMD-SHELL",
             "kafka-broker-api-versions --bootstrap-server localhost:9092 > /dev/null 2>&1"]
      interval: 15s
      timeout: 10s
      retries: 10
      start_period: 30s

  # ── Flask API ──────────────────────────────────────────────────────────────
  flask:
    build:
      context: .
      dockerfile: Dockerfile
    container_name: traffic_flask
    restart: unless-stopped
    ports:
      - "5000:5000"
    environment:
      # Database connections — use Docker service names, NOT localhost
      MONGO_URI:      mongodb://mongodb:27017/
      MYSQL_HOST:     mysql
      MYSQL_PORT:     "3306"
      MYSQL_USER:     root
      MYSQL_PASSWORD: rootpassword
      MYSQL_DATABASE: traffic_db
      # Kafka — internal listener
      KAFKA_BOOTSTRAP: kafka:29092
      # Admin secret (change in production!)
      ADMIN_SECRET:   ADMIN123
      FLASK_ENV:      production
    depends_on:
      mongodb:
        condition: service_healthy
      mysql:
        condition: service_healthy
      # Kafka is optional for the Flask API itself; depends_on without
      # condition so Flask still starts even if Kafka is slow.
      kafka:
        condition: service_started
    # BUG FIX: NO volume mount here — mounting . would shadow the files
    # already copied into the image by Dockerfile's COPY . .
    # If you want live-reload during development, uncomment the next two lines:
    # volumes:
    #   - .:/app

  # ── Data Simulator (optional — comment out if running manually) ───────────
  simulator:
    build:
      context: .
      dockerfile: Dockerfile
    container_name: traffic_simulator
    restart: unless-stopped
    command: ["python", "data_simulator.py"]
    environment:
      API_BASE:        http://flask:5000/api
      KAFKA_BOOTSTRAP: kafka:29092
    depends_on:
      flask:
        condition: service_started
      kafka:
        condition: service_started

volumes:
  mongodb_data:
  mysql_data: