Microservices Experimental

An experimental ecommerce-microservice projects for learning and testing

Service Diagram

🎨 Database Designs

Read more from here.

Service Decomposition

┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐
│   User Service  │  │ Product Service │  │Inventory Service│
│                 │  │                 │  │                 │
│ • users         │  │ • categories    │  │ • inventory     │
│ • addresses     │  │ • products      │  │ • reservations  │
└─────────────────┘  └─────────────────┘  └─────────────────┘

┌─────────────────┐  ┌─────────────────┐
│  Order Service  │  │ Payment Service │
│                 │  │                 │
│ • orders        │  │ • payments      │
│ • order_items   │  │ • payment_hist  │
│ • order_addr    │  │                 │
│ • status_hist   │  │                 │
└─────────────────┘  └─────────────────┘

💼 Business Capability Alignment

• 🧑‍💼 User Service: User management, profiles, addresses (node.js)
• 📦 Product Service: Product catalog, categories (java)
• 📊 Inventory Service: Stock management, reservations (go)
• 🛒 Order Service: Order processing, order lifecycle (go)
• 💳 Payment Service: Payment processing, transactions (rust)

🔄 Communication Patterns

Synchronous (API Calls):

Order Service → Product Service (validate products)
Order Service → User Service (validate user)
Order Service → Inventory Service (reserve stock)
Order Service → Payment Service (process payment)

Asynchronous (Events):

Order Created → Inventory Service (reserve stock)
Payment Completed → Order Service (update status)
Order Shipped → User Service (send notification)

🛠️ Technology Stack

API Layer:

• API Gateway (Kong/Ambassador)
• Service mesh (Istio)

Data Layer:

• PostgreSQL per service
• Redis for caching
• Message broker (RabbitMQ/Kafka)

Authorization & Authentication

• Keycloak

Infrastructure:

• Kubernetes for orchestration
• Docker containers
• Helm charts for deployment

Observability:

• Prometheus + Grafana
• Jaeger for tracing
• ELK stack for logs

Database initialize

podman compose exec -it database "PGPASSWORD=zRSuuR1Pz9VdJB psql -U antman -d postgres <<EOF
CREATE ROLE service_ops WITH LOGIN PASSWORD 'Ycb0zaTdhkybmF';
CREATE DATABASE user_service;
CREATE DATABASE inventory_service;
CREATE DATABASE product_service;
CREATE DATABASE order_service;
CREATE DATABASE payment_service;

for db in user_service inventory_service product_service order_service payment_service
do
  podman compose exec -it database "PGPASSWORD=zRSuuR1Pz9VdJB psql -U antman -d "$db" <<EOF
    GRANT USAGE ON SCHEMA public TO service_ops;
    GRANT SELECT, INSERT, UPDATE ON ALL TABLES IN SCHEMA public TO service_ops;
    ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT, INSERT, UPDATE ON TABLES TO service_ops;
    exit && exit;
  EOF"
done