Go-grpc-graphql-microservice

A scalable and modular microservice-based application built with Go, gRPC, and GraphQL. This project demonstrates how to integrate multiple services using gRPC while exposing a unified GraphQL API Gateway for easy querying.

Overview

This project consists of three independent microservices:

1. Account Service - Manages user accounts.
2. Catalog Service - Handles product listings (uses Elasticsearch for storage).
3. Order Service - Processes orders (linked to PostgreSQL).
4. GraphQL API Gateway - Provides a single access point to interact with all services.

Features

✔️ Microservices architecture with gRPC communication
✔️ GraphQL API for querying and mutations
✔️ PostgreSQL and Elasticsearch for data storage
✔️ Docker Compose setup for easy deployment
✔️ Modular and scalable design

Getting Started

1. Clone the Repository

git clone https://github.com/Devisrisamidurai/Go-grpc-graphql-microservice.git
cd Go-grpc-graphql-microservice

2. Run the Services with Docker

Ensure you have Docker and Docker Compose installed, then start the services:

docker-compose up -d --build

3. Access the GraphQL Playground

Once the services are up, visit:
➡ http://localhost:8000/playground

Example GraphQL Queries

Fetch All Accounts

query {
  accounts {
    id
    name
  }
}

Create a New Account

mutation {
  createAccount(account: {name: "John Doe"}) {
    id
    name
  }
}

Retrieve Products with Filtering and Pagination

query {
  products(pagination: {skip: 0, take: 10}, filter: "laptop") {
    id
    name
    price
  }
}

Place an Order

mutation {
  createOrder(order: {accountId: "123", products: [{id: "456", quantity: 2}]}) {
    id
    totalPrice
    products {
      name
      quantity
    }
  }
}

Fetch Account Details with Order History

query {
  account(id: "123") {
    name
    orders {
      id
      totalPrice
      products {
        name
        quantity
        price
      }
    }
  }
}

Tech Stack

• Go - Core backend language
• gRPC - Service-to-service communication
• GraphQL - API Gateway for data querying
• PostgreSQL - Relational database for accounts and orders
• Elasticsearch - Search engine for products
• Docker & Docker Compose - Containerized deployment

How It Works

1. Frontend/Client makes a GraphQL query.
2. GraphQL API Gateway routes the request to the appropriate gRPC service.
3. gRPC Services process the request and interact with their respective databases.
4. Response is returned to the client via the GraphQL Gateway.

Contributing

Contributions are welcome! Feel free to fork the repository and submit a pull request.

License

This project is open-source and available under the MIT License.