📌 Order Worker Service

📢 This project is now fully documented in English.
For the original version in Spanish, switch to the main branch.

Reactive microservice built with Spring WebFlux, Kafka, Redis, and MongoDB for real-time order processing and enrichment using external Go APIs.

📑 Table of Contents

• Project Overview
• Key Features
• Tech Stack
• Setup
• Run the Project
• Sample Payload
• Testing
• Scalability and Optimization

🚀 Project Overview

This project processes orders received through Kafka by enriching them with customer and product data via Go APIs. Orders are validated and stored in MongoDB. It also includes resilience mechanisms like retries and circuit breakers using Resilience4j.

✅ Key Features

• Reactive Kafka consumer with Spring WebFlux
• External data enrichment using Go APIs
• Redis for caching and distributed locks
• MongoDB for order persistence
• Retry and circuit breaker mechanisms with Resilience4j

🛠️ Tech Stack

• Java 21, Spring Boot 3.x, Spring WebFlux
• Apache Kafka – event streaming
• Redis – caching + locks
• MongoDB – order storage
• Go – mock APIs for customer and product enrichment
• Resilience4j, Reactor Retry
• JUnit 5, Mockito
• Docker (planned)

⚙️ Setup

Requirements

• Java 17+
• Maven
• Docker (Mongo, Redis, Kafka)
• Go

Configuration

Update application.properties:

spring.kafka.bootstrap-servers=localhost:9092
spring.data.mongodb.uri=mongodb://localhost:27017/pedidosDB
spring.data.redis.host=localhost
spring.data.redis.port=6379

▶️ Run the Project

1. Start Kafka, Redis, MongoDB, and Go APIs
2. Build and run the app:

mvn spring-boot:run

3. Start Go APIs (from /go-api):

go run main.go

APIs:

• GET /product
• GET /customer

📃 Sample Payload

{
  "orderId": "order-100",
  "customerId": "Freyder-111",
  "products": [
    {
      "productId": "product-100",
      "name": "Iphone",
      "price": 2000
    }
  ]
}

🧪 Testing

Run tests with:

mvn test

Covered scenarios:

• Successful order processing
• Inactive client
• Product not found
• Redis lock handling

📈 Scalability and Optimization

• MongoDB indexes: created on orderId and customerId
• Redis caching: reduces external API calls
• Retry & Circuit Breaker: for API resilience