Go Microservices Architecture with GraphQL and gRPC

📋 Overview

This project implements a modern microservices architecture using Go, with GraphQL as the API gateway and gRPC for inter-service communication.

🏗️ Architecture

The system follows a microservices architecture with the following components:

• GraphQL API Gateway: Provides a unified entry point for clients
• Account Service: Manages user accounts and authentication
• Catalog Service: Handles product information and search functionality
• Order Service: Processes orders and manages the purchase lifecycle

Technology Stack

• Go: Primary programming language
• GraphQL: API gateway interface
• gRPC: Inter-service communication
• PostgreSQL: Database for Account and Order services
• Elasticsearch: Database for Catalog service
• Docker: Containerization and deployment

🚀 Getting Started

Prerequisites

• Go 1.21 or higher
• Docker and Docker Compose
• PostgreSQL
• Elasticsearch

Installation

1. Clone the repository

2. Start the services using Docker Compose:

   docker-compose up -d --build
   

3. Access the GraphQL playground at http://localhost:8000/playground

🔄 gRPC Setup

For generating gRPC files, follow these steps:

1. Install Protocol Buffers compiler:

   wget https://github.com/protocolbuffers/protobuf/releases/download/v23.0/protoc-23.0-linux-x86_64.zip
   unzip protoc-23.0-linux-x86_64.zip -d protoc
   sudo mv protoc/bin/protoc /usr/local/bin/
   

2. Install Go plugins for Protocol Buffers:

   go install google.golang.org/protobuf/cmd/protoc-gen-go@latest
   go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@latest
   

3. Update PATH:

   export PATH="$PATH:$(go env GOPATH)/bin"
   source ~/.bashrc
   

4. Generate gRPC code:

   mkdir -p pb
   # Add this to your proto files: option go_package = "./pb";
   protoc --go_out=./pb --go-grpc_out=./pb account.proto
   

📡 API Usage

GraphQL Examples

Query Accounts

query {
  accounts {
    id
    name
  }
}

Create an Account

mutation {
  createAccount(account: { name: "New Account" }) {
    id
    name
  }
}

Query Products

query {
  products {
    id
    name
    price
  }
}

Create a Product

mutation {
  createProduct(
    product: { name: "New Product", description: "A new product", price: 19.99 }
  ) {
    id
    name
    price
  }
}

Create an Order

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

Query Account with Orders

query {
  accounts(id: "account_id") {
    name
    orders {
      id
      createdAt
      totalPrice
      products {
        name
        quantity
        price
      }
    }
  }
}

Advanced Queries

Pagination and Filtering

query {
  products(pagination: { skip: 0, take: 5 }, query: "search_term") {
    id
    name
    description
    price
  }
}

📦 Service Details

Account Service

Manages user accounts, authentication, and authorization.

Catalog Service

Provides product catalog functionality with advanced search capabilities using Elasticsearch.

Order Service

Handles order creation, processing, and management with a complete history of purchases.

GraphQL API Gateway

Unifies all services under a single GraphQL API, providing a seamless experience for client applications.