🚀 Project Structure

Service Name	Description	Port
config-server	Provides configuration for all microservices via config-repo.	8888
eureka-server	Handles service discovery and registration.	8761
api-gateway	Acts as the single entry point for all microservices.	8080
authentication-service	Manages user registration and authentication.	8090
product-service	Manages product information (create, update, list).	8081
order-service	Handles order creation and management.	8083
inventory-service	Tracks stock quantities.	8082
config-repo	Repository containing configuration files for all services. Store local or github
supplier-service	Manages supplier information (create, update, list).	8085

---

🗄️ Technologies Used

• Java 21+
• Spring Boot / Spring Cloud
• PostgreSQL (database)
• Eureka Server (service discovery)
• Spring Cloud Config Server
• Spring Cloud Gateway
• Docker & Docker Compose
• Spring Security / JWT

---

⚙️ Startup Order

Services should be started in the following order:

1. 🧩 config-server
2. 🛰️ eureka-server
3. 🌉 api-gateway
4. 🔐 authentication-service
5. 🛒 product-service
6. 📦 order-service
7. 📊 inventory-service
8. 📦 supplier-service

Each service contains its own application.yml with configuration and discovery settings.

---

🐳 Run with Docker Compose

To start all services using Docker, run the following command in the project root:

docker-compose up --build

To stop all services, run the following command:

docker-compose down

Connect to Database

docker exec -it <container_name> psql -U postgres -d <database_name>

1. Infrastructure

docker-compose up -d

2. Core Services

cd config-server && mvn spring-boot:run cd discovery-service && mvn spring-boot:run cd api-gateway && mvn spring-boot:run

3. Business Services

cd product-service && mvn spring-boot:run cd inventory-service && mvn spring-boot:run cd order-service && mvn spring-boot:run cd customer-service && mvn spring-boot:run cd supplier-service && mvn spring-boot:run cd authentication-service && mvn spring-boot:run

4. Test Flow

1. Register

POST /api/auth/register

2. Login (token al)

POST /api/auth/login

3. Create Product (token ile)

POST /api/products Authorization: Bearer {token}

4. Create Inventory

POST /api/inventory

5. Create Customer

POST /api/customers

6. Create Order (event trigger)

POST /api/orders

URLS

• Prometheus: http://localhost:9090

• Grafana: http://localhost:3000 (admin/admin)

• Actuator Endpoints (örnek):

• http://localhost:8081/actuator

• http://localhost:8081/actuator/health

• http://localhost:8081/actuator/metrics

• http://localhost:8081/actuator/prometheus

GRAFANA

• http://localhost:3000

• Login: admin/admin

• Add Data Source → Prometheus

• URL: http://prometheus:9090

• Save & Test

• Import Dashboard:

• Dashboard ID: 11378 (JVM Micrometer)

• Dashboard ID: 4701 (Spring Boot Statistics)

PROMETHEUS QUERIES

CPU Usage

• process_cpu_usage{application="product-service"}

Memory Usage

• jvm_memory_used_bytes{application="product-service"}

HTTP Requests

• http_server_requests_seconds_count{uri="/api/products"}

Custom metrics

• product_created_total
• product_cache_hit_total
• product_cache_miss_total
• order_created_total
• order_processing_time_seconds_sum

Health Check Endpoints

Health check

• curl http://localhost:8081/actuator/health

Metrics

• curl http://localhost:8081/actuator/metrics

Prometheus format

• curl http://localhost:8081/actuator/prometheus

Zipkin

• http://localhost:9411

Zipkin Scanario

- 1. Login (get Token)

POST http://localhost:8080/api/auth/login
{
  "username": "admin",
  "password": "admin123"
}

-  2. Create Order (trace all services)
POST http://localhost:8080/api/orders
Authorization: Bearer {token}
{
  "customerId": 1,
  "warehouseId": 1,
  "items": [
    {
      "productId": 1,
      "quantity": 2
    }
  ]
}

• 3. Zipkin UI'

1. Service Dependency Graph - Which services are calling which services

2. Trace Timeline:

   • API Gateway → Order Service
   • Order Service → Product Service (Feign)
   • Order Service → Inventory Service (Feign)
   • Inventory Service → Product Service (Feign)
   • Order Service → RabbitMQ (Event)
   • Customer Service ← RabbitMQ (Event)

3. Span Details:

   • createOrder span
   • processOrderItems span
   • reserveInventory span
   • acquireLock span
   • database query span
   • cache hit/miss events

Zipkin Query

Zipkin UI:

• Service Name: order-service
• Span Name: createOrder
• Min Duration: 100ms (find slow requests)
• Tags: customer.id=1

9. Log Output example

2025-11-03 15:30:45 INFO  [order-service,a1b2c3d4e5f6g7h8,i9j0k1l2m3n4o5p6] Creating order for customer: 1
2025-11-03 15:30:45 DEBUG [order-service,a1b2c3d4e5f6g7h8,q7r8s9t0u1v2w3x4] Calling product-service for product: 1
2025-11-03 15:30:45 INFO  [product-service,a1b2c3d4e5f6g7h8,y5z6a7b8c9d0e1f2] Product found in cache: 1
2025-11-03 15:30:45 DEBUG [order-service,a1b2c3d4e5f6g7h8,g3h4i5j6k7l8m9n0] Calling inventory-service
2025-11-03 15:30:45 INFO  [inventory-service,a1b2c3d4e5f6g7h8,o1p2q3r4s5t6u7v8] Lock acquired for product: 1
2025-11-03 15:30:45 INFO  [inventory-service,a1b2c3d4e5f6g7h8,o1p2q3r4s5t6u7v8] Stock reserved: product=1, quantity=2
2025-11-03 15:30:45 INFO  [order-service,a1b2c3d4e5f6g7h8,i9j0k1l2m3n4o5p6] Order created successfully: ORD-20251103153045

CI/CD

Stock Management System