Docker Setup - StreamLine Logistics

StreamLine Logistics uses Docker Compose to orchestrate all microservices and their dependencies. This guide explains the Docker setup in detail.

Docker Compose Overview

The project uses a single docker-compose.yml file that defines:

3 microservices (Order, Inventory, Tracking)
1 service discovery server (Eureka)
3 databases (PostgreSQL, MySQL, MongoDB)
1 custom bridge network
3 persistent volumes

Architecture

Complete Docker Compose Configuration

Here’s the complete docker-compose.yml from the project:

services:
  eureka-server:
    container_name: eureka-server
    build:
      context: .
      dockerfile: ./microservice-eureka/Dockerfile
    image: eureka-service:latest
    ports:
      - "8761:8761"
    networks:
      - microservices-network
    
  order-service:
    container_name: order-service
    build:
      context: .
      dockerfile: ./microservice-order/Dockerfile
    image: order-service:latest
    ports:
      - "8090:8090"
    networks:
      - microservices-network
    depends_on:
      - eureka-server
  
  inventory-service:
    container_name: inventory-service
    build:
      context: .
      dockerfile: ./microservice-inventory/Dockerfile
    image: inventory-service:latest
    ports: 
      - "9090:9090"
    networks:
      - microservices-network
    depends_on:
      - eureka-server
  
  tracking-service:
    container_name: tracking-service
    build:
      context: .
      dockerfile: ./microservice-tracking/Dockerfile
    image: tracking-service:latest
    ports:
      - "8091:8091"
    networks:
      - microservices-network
    depends_on:
      - eureka-server
  
  order-db:
    container_name: order_db
    image: postgres:15
    restart: always
    environment:
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: password
      POSTGRES_DB: orderdb
    ports:
      - "5432:5432"
    networks:
      - microservices-network
    volumes:
      - orderdb-data:/var/lib/postgresql/data

  inventory-db:
    container_name: inventory_db
    image: mysql:8
    restart: always
    environment:
      MYSQL_ROOT_USER: root
      MYSQL_ROOT_PASSWORD: password
      MYSQL_DATABASE: inventorydb
    ports:
      - "3306:3306"
    networks:
      - microservices-network
    volumes:
      - inventorydb-data:/var/lib/mysql
  
  traking-db:
    container_name: tracking_db
    image: mongo:latest
    restart: always
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: password
    ports:
      - "27017:27017"
    networks:
      - microservices-network
    volumes:
      - trackingdb-data:/data/db

networks:
  microservices-network:
    driver: bridge

volumes:
  orderdb-data:
  inventorydb-data:
  trackingdb-data:

Service Breakdown

Eureka Server

Service discovery and registration server.

eureka-server:
  container_name: eureka-server
  build:
    context: .
    dockerfile: ./microservice-eureka/Dockerfile
  image: eureka-service:latest
  ports:
    - "8761:8761"
  networks:
    - microservices-network

Key Points:

Runs on port 8761
No dependencies (starts first)
Dashboard accessible at http://localhost:8761
All other services register with this instance

Order Service

Handles order management operations.

order-service:
  container_name: order-service
  build:
    context: .
    dockerfile: ./microservice-order/Dockerfile
  image: order-service:latest
  ports:
    - "8090:8090"
  networks:
    - microservices-network
  depends_on:
    - eureka-server

Key Points:

Runs on port 8090
Depends on Eureka Server
Uses PostgreSQL database (order_db)
Connects to database at order_db:5432

Inventory Service

Manages inventory and stock levels.

inventory-service:
  container_name: inventory-service
  build:
    context: .
    dockerfile: ./microservice-inventory/Dockerfile
  image: inventory-service:latest
  ports: 
    - "9090:9090"
  networks:
    - microservices-network
  depends_on:
    - eureka-server

Key Points:

Runs on port 9090
Depends on Eureka Server
Uses MySQL database (inventory_db)
Connects to database at inventory_db:3306
Includes OpenAPI/Swagger documentation

Tracking Service

Tracks shipment status and location.

tracking-service:
  container_name: tracking-service
  build:
    context: .
    dockerfile: ./microservice-tracking/Dockerfile
  image: tracking-service:latest
  ports:
    - "8091:8091"
  networks:
    - microservices-network
  depends_on:
    - eureka-server

Key Points:

Runs on port 8091
Depends on Eureka Server
Uses MongoDB database (tracking_db)
Connects to database at tracking_db:27017

Database Configuration

PostgreSQL (Order Database)

order-db:
  container_name: order_db
  image: postgres:15
  restart: always
  environment:
    POSTGRES_USER: postgres
    POSTGRES_PASSWORD: password
    POSTGRES_DB: orderdb
  ports:
    - "5432:5432"
  networks:
    - microservices-network
  volumes:
    - orderdb-data:/var/lib/postgresql/data

Configuration:

Image: PostgreSQL 15
Database: orderdb
User: postgres
Password: password
Port: 5432
Volume: orderdb-data (persistent storage)

Change the default password in production environments.

MySQL (Inventory Database)

inventory-db:
  container_name: inventory_db
  image: mysql:8
  restart: always
  environment:
    MYSQL_ROOT_USER: root
    MYSQL_ROOT_PASSWORD: password
    MYSQL_DATABASE: inventorydb
  ports:
    - "3306:3306"
  networks:
    - microservices-network
  volumes:
    - inventorydb-data:/var/lib/mysql

Configuration:

Image: MySQL 8
Database: inventorydb
Root User: root
Root Password: password
Port: 3306
Volume: inventorydb-data (persistent storage)

MongoDB (Tracking Database)

traking-db:
  container_name: tracking_db
  image: mongo:latest
  restart: always
  environment:
    MONGO_INITDB_ROOT_USERNAME: root
    MONGO_INITDB_ROOT_PASSWORD: password
  ports:
    - "27017:27017"
  networks:
    - microservices-network
  volumes:
    - trackingdb-data:/data/db

Configuration:

Image: MongoDB latest
Root Username: root
Root Password: password
Port: 27017
Volume: trackingdb-data (persistent storage)

Note the typo in the service name: traking-db should be tracking-db.

Networking

Bridge Network

networks:
  microservices-network:
    driver: bridge

All services run on a custom bridge network named microservices-network. This allows:

Container-to-container communication using container names
Isolated network from other Docker containers
DNS resolution for service discovery

Example: Order Service connects to PostgreSQL using hostname order_db instead of localhost.

Persistent Volumes

volumes:
  orderdb-data:
  inventorydb-data:
  trackingdb-data:

Docker volumes ensure data persistence across container restarts:

Volume	Database	Purpose
orderdb-data	PostgreSQL	Stores order data
inventorydb-data	MySQL	Stores inventory data
trackingdb-data	MongoDB	Stores tracking data

Managing Volumes

docker volume ls | grep streamline

Docker Commands Reference

Starting Services

docker compose up -d

Stopping Services

docker compose stop

Monitoring Services

docker compose logs -f

Service Management

docker compose restart order-service

Dockerfile Examples

While the complete Dockerfiles are in each microservice directory, they typically follow this pattern:

FROM eclipse-temurin:17-jdk-alpine

WORKDIR /app

COPY microservice-*/target/*.jar app.jar

EXPOSE <port>

ENTRYPOINT ["java", "-jar", "app.jar"]

Environment-Specific Configurations

Development Environment

For local development, you might want to modify docker-compose.yml:

order-service:
  # ... other config
  environment:
    - SPRING_PROFILES_ACTIVE=dev
  volumes:
    - ./microservice-order/src:/app/src  # Hot reload

Production Environment

Create a separate docker-compose.prod.yml:

services:
  order-db:
    environment:
      POSTGRES_PASSWORD: ${DB_PASSWORD}  # Use secrets
    deploy:
      resources:
        limits:
          cpus: '0.5'
          memory: 512M

Use with:

docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d

Troubleshooting

Container Won’t Start

# Check container logs
docker compose logs <service-name>

# Check container status
docker compose ps -a

# Inspect container
docker inspect <container-name>

Network Issues

# List networks
docker network ls

# Inspect network
docker network inspect microservices-network

# Recreate network
docker compose down
docker network prune
docker compose up -d

Volume Issues

# Check volume mounts
docker inspect <container-name> | grep -A 10 Mounts

# Clean unused volumes
docker volume prune

Database Connection Issues

# Test PostgreSQL connection
docker compose exec order-service nc -zv order_db 5432

# Test MySQL connection
docker compose exec inventory-service nc -zv inventory_db 3306

# Test MongoDB connection
docker compose exec tracking-service nc -zv tracking_db 27017

Performance Optimization

Resource Limits

Add resource constraints to prevent any service from consuming too many resources:

order-service:
  # ... other config
  deploy:
    resources:
      limits:
        cpus: '1.0'
        memory: 1G
      reservations:
        cpus: '0.5'
        memory: 512M

Health Checks

Add health checks for better orchestration:

order-service:
  # ... other config
  healthcheck:
    test: ["CMD", "curl", "-f", "http://localhost:8090/actuator/health"]
    interval: 30s
    timeout: 10s
    retries: 3
    start_period: 40s

Next Steps

Review Configuration for detailed service configuration
Learn about customizing environment variables
Explore production deployment strategies

Getting Started

Setup & Deployment

Microservices

Infrastructure

Operations

​Docker Compose Overview

​Architecture

​Complete Docker Compose Configuration

​Service Breakdown

​Eureka Server

​Order Service

​Inventory Service

​Tracking Service

​Database Configuration

​PostgreSQL (Order Database)

​MySQL (Inventory Database)

​MongoDB (Tracking Database)

​Networking

​Bridge Network

​Persistent Volumes

​Managing Volumes

​Docker Commands Reference

​Starting Services

​Stopping Services

​Monitoring Services

​Service Management

​Dockerfile Examples

​Environment-Specific Configurations

​Development Environment

​Production Environment

​Troubleshooting

​Container Won’t Start

​Network Issues

​Volume Issues

​Database Connection Issues

​Performance Optimization

​Resource Limits

​Health Checks

​Next Steps

Build docs developers (and LLMs) love

Docker Compose Overview

Architecture

Complete Docker Compose Configuration

Service Breakdown

Eureka Server

Order Service

Inventory Service

Tracking Service

Database Configuration

PostgreSQL (Order Database)

MySQL (Inventory Database)

MongoDB (Tracking Database)

Networking

Bridge Network

Persistent Volumes

Managing Volumes

Docker Commands Reference

Starting Services

Stopping Services

Monitoring Services

Service Management

Dockerfile Examples

Environment-Specific Configurations

Development Environment

Production Environment

Troubleshooting

Container Won’t Start

Network Issues

Volume Issues

Database Connection Issues

Performance Optimization

Resource Limits

Health Checks

Next Steps