E-Commerce Microservices Platform with Native SQL Reporting

A Spring Boot microservices showcase that demonstrates:

• Spring IoC / dependency injection across all layers
• service-specific PostgreSQL databases
• REST-based service-to-service communication
• native SQL reporting queries in the reporting-service
• Java Streams for aggregation and result shaping
• Docker Compose orchestration for local setup

Services

• product-service (:8081) - product catalog, search, inventory validation/decrement
• order-service (:8082) - order placement and status tracking, calls product service
• reporting-service (:8083) - syncs completed orders from the order service and exposes reporting endpoints
• api-gateway (:8080) - routes /api/products/**, /api/orders/**, /api/reports/**

Quick Start

Prerequisites

• Docker + Docker Compose
• Java 17 and Maven (optional, for local build without containers)

Run with Docker Compose

docker compose up --build

The platform exposes these ports:

• 8080 - API gateway
• 8081 - product-service
• 8082 - order-service
• 8083 - reporting-service
• 5433 - product PostgreSQL
• 5434 - order PostgreSQL
• 5435 - reporting PostgreSQL

Reporting Service Endpoints

The reporting-service routes are exposed through the API gateway at /api/reports.

• POST /api/reports/sync - import completed orders into the reporting database
• GET /api/reports/monthly-sales - monthly sales grouped by customer and month
• GET /api/reports/customer-spending - total spending per customer
• GET /api/reports/top-products-all-time - all-time top selling products
• GET /api/reports/past-month-top-products - top products from the last 30 days
• GET /api/reports/past-year-top-products - top products from the last 12 months
• GET /api/reports/top-products-by-month?month=YYYY-MM - top products for a specific month

Example API Flow

1. Create product via gateway:

curl -X POST http://localhost:8080/api/products   -H 'Content-Type: application/json'   -d '{"name":"Laptop","description":"Ultrabook","price":1200,"stock":15}'

2. Place order via gateway:

curl -X POST http://localhost:8080/api/orders   -H 'Content-Type: application/json'   -d '{
    "customerId": 101,
    "items": [
      {"productId":1,"productName":"Laptop","quantity":2,"unitPrice":1200}
    ]
  }'

3. Sync completed orders into reporting DB:

curl -X POST http://localhost:8080/api/reports/sync

4. Query reporting endpoints:

curl http://localhost:8080/api/reports/monthly-sales
curl http://localhost:8080/api/reports/customer-spending
curl http://localhost:8080/api/reports/top-products-all-time
curl http://localhost:8080/api/reports/past-month-top-products
curl http://localhost:8080/api/reports/top-products-by-month?month=2026-05

Reporting Service Highlights

• reporting-service syncs completed orders from order-service into its own reporting database
• uses native SQL queries for aggregation and ranking
• exposes multiple reporting views for monthly sales, customer spending, and top selling products

Project Structure

.
├── api-gateway
├── product-service
├── order-service
├── reporting-service
├── docker-compose.yml
└── pom.xml