A modern, scalable microservices application built with Go, featuring multiple services that communicate with each other through a central API Gateway. This project demonstrates microservices best practices, containerization, and database integration.

• Technology Stack

• Architecture Overview

• Services

• Project Structure

• Prerequisites

• Installation & Setup

• API Documentation

• Testing

• Development

• Troubleshooting

• Contributing

• License

• Go (Golang) - Primary programming language for all microservices

• Gin Framework - HTTP web framework for the API Gateway and services

• GORM - ORM library for database operations

• PostgreSQL - Relational database for User Service

• MongoDB - NoSQL database for Product Service

• Docker - Containerization platform

• Docker Compose - Multi-container orchestration

• Environment Configuration - Using .env files

• RESTful APIs - For service-to-service communication

• JSON - Data exchange format

This project implements a microservices architecture with the following components:

            Client
              |
              v
           Gateway
              |
     +----------------+
     |                |
     v                v
User Service    Product Service
     |                |
     v                v
 PostgreSQL        MongoDB

• Client: Sends requests to the system.

• Gateway: Acts as the entry point and routes requests to the appropriate microservices.

• User Service: Handles user-related operations and stores data in PostgreSQL.

• Product Service: Manages product-related operations and stores data in MongoDB.

• Language: Go

• Database: PostgreSQL

• Description: Manages user data and authentication

• Language: Go

• Database: MongoDB

• Description: Manages product data and inventory

• Language: Go

• Framework: Gin

• Description: Routes requests to the appropriate service

/project-root

│

├── /api-gateway

│ ├── main.go

│ └── ...

│

├── /user-service

│ ├── main.go

│ └── ...

│

├── /product-service

│ ├── main.go

│ └── ...

│

├── docker-compose.yml

├── .env.example

└── README.md

• Docker

• Docker Compose

• Go (for local development)

1. Create an Environment File

Copy the contents of .env.example into a new file named .env in the project root and adjust values as needed.

2. Start with Docker Compose

docker-compose up --build

This command will build and start your services and databases.

• POST /users

• Description: Create a new user

• Request Body: { "username": "string", "password": "string" }

• Response: { "id": "string", "username": "string" }

• GET /users/{id}

• Description: Get user details by ID

• Response: { "id": "string", "username": "string" }

• POST /products

• Description: Create a new product

• Request Body: { "name": "string", "price": "number" }

• Response: { "id": "string", "name": "string", "price": "number" }

• GET /products/{id}

• Description: Get product details by ID

• Response: { "id": "string", "name": "string", "price": "number" }

You can send requests to user and product endpoints through the Gateway (http://localhost:8000):

• Example: POST http://localhost:8000/users

• Example: POST http://localhost:8000/products

To run the services locally without Docker:

1. User Service

cd user-service

go run main.go

2. Product Service

cd product-service

go run main.go

3. API Gateway

cd api-gateway

go run main.go

• Database Connection Issues: Ensure your .env file has the correct database connection strings.

• Service Not Starting: Check the logs for error messages and ensure all dependencies are installed.

Contributions via pull requests or issues are welcome.

This project is licensed under the MIT License.