NDK-RPC-Cluster

Enterprise-grade RPC cluster system with load balancing, fault tolerance, service discovery and automatic failover support

🚀 Features

• 🔄 Auto Replica Creation - Automatic Replica Creation if in 10 seconds more than threshold requests are received with respect to number of replicas
• ⚡ Custom Threshold - Configure request threshold for auto-scaling (default: 2000)
• 🌐 Protocol Support - Support for both HTTP and HTTPS protocols
• 🔌 Port Configuration - Flexible port management with portRequired option
• 🔄 Load Balancing - Round-robin distribution across replicas
• ⚡ Fault Tolerance - Automatic retry mechanisms and failover
• 🔍 Service Discovery - Global registry for service management
• 📡 RPC Support - Remote procedure calls with full cluster support
• 🛡️ Error Handling - Comprehensive error management
• 🔧 Easy Setup - Simple configuration and deployment

📦 Installation

npm install ndk-rpc-cluster
# or
yarn add ndk-rpc-cluster
# or
pnpm add ndk-rpc-cluster

🔄 Recent Updates

• Added support for custom protocols (HTTP/HTTPS)
• Added portRequired option for flexible URL generation
• Improved error handling and logging
• Enhanced configuration options for better control

🏗️ Architecture

🚀 Quick Start

1. Create Load Balancer with Replicas

Load Balancer 1

import ndk_load_balancer from "ndk-rpc-cluster/loadBalancer";

let registerFns = [
  {
    function_name: "add",
    function_block: ({ a, b }) => a + b,
  },
];

let config = {
  replicas: 3, // replicas want to create
  port: 3000, // port of load balancer
  register_functions: registerFns, // function to register on replicas
  threashold: 30000 // it means if req reach 30,000 then creates new replica
};

const lb = new ndk_load_balancer(config);
await lb.start(); // start the load balancer server

Load Balancer 2

import ndk_load_balancer from "ndk-rpc-cluster/loadBalancer";

let registerFns = [
  {
    function_name: "sub",
    function_block: ({ a, b }) => a - b,
  },
];

let config = {
  replicas: 3, // replicas want to create
  port: 4000, // port of load balancer
  register_functions: registerFns, // function to register on replicas
  threashold: 50000, // it means if req reach 50,000 then creates new replica
};

const lb = new ndk_load_balancer(config);
await lb.start(); // start the load balancer server

2. Setup Global Registry

import GlobalRegister from "ndk-rpc-cluster/registry";

const global = new GlobalRegister({
  createMiddleware: true, // it must true , it will create middle server
});

let keys = {
  AddService: {
    host: "localhost", // load balancer host
    port: 3000, // load balancer port
    protocol: "http", // http or https
    portRequired: true // include port in service URL (default: true)
  },
  SubService: {
    host: "localhost", // load balancer host
    port: 4000, // load balancer port
    protocol: "http", // http or https
    portRequired: false // service will be accessed without port in URL
  },
};

global.registerKeys(keys);
await global.start(); // start the global registry + middle server
// Registry runs on port 3331, Middleware on port 4132

3. Create Client

import { Client } from "ndk-rpc-cluster/client";

const client = new Client();

const response = await client.request({
  method: "add", // method name to run
  params: {
    // parameters to pass else {}
    a: 2,
    b: 3,
  },
  key: "AddService", // key of service that we declare in Global Registry
});

console.log("Res: ", response);

🛠️ Configuration

Load Balancer Options

Option	Type	Default	Description
port	number	-	Load balancer server port
replicas	number	-	Number of replica servers
basePort	number	-	Starting port for replicas
protocol	string	"http"	Protocol to use (http/https)
portRequired	boolean	true	Whether to include port in URLs
register_functions	array	-	Functions to register on replicas

Registry Options

Option	Type	Default	Description
createMiddleware	boolean	true	Auto-create middleware server

🔧 Scripts

# Start complete cluster
npm run cluster:start

# Start individual components
npm run start:registry
npm run start:load-balancer
npm run start:middleware

# Run tests
npm test
npm run test:client
npm run test:server

# Development mode
npm run dev

🌐 Default Ports

• Global Registry: 3331
• Middleware Server: 4132
• Load Balancer: 3000 (configurable)
• Replica Servers: 9000+ (basePort + index)

🔄 How It Works

1. Registry manages service discovery and routing
2. Middleware handles request forwarding
3. Load Balancer distributes requests across replicas
4. Replicas execute the actual RPC methods
5. Client makes requests through the registry

⚠️ Important Notes

• Global Registry can only have one instance - multiple instances will throw errors
• All components use ES modules (import/export)
• Requires Node.js 16+ for optimal performance
• Functions should be pure and stateless for best results

🤝 Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

👨‍💻 Author

Navnath Kadam

• GitHub: @ndk123-web
• Email: ndk123.web@gmail.com

🙏 Support

If you find this project helpful, please give it a ⭐ on GitHub!

---

Built with ❤️ for the Node.js community