Node Cache Service

A lightweight and efficient caching solution built with Node.js and TypeScript using the node-cache package. This project provides an in-memory caching service to improve application performance by storing and reusing frequently accessed data.

Overview

This project is designed to demonstrate how to use caching to optimize data retrieval in a Node.js application. The caching layer allows repeated requests for the same data to be handled quickly by leveraging in-memory storage, significantly reducing database or API calls.

Key Features

• Implements caching using the node-cache library.
• Provides data retrieval via cached data or fresh data.
• Automatically refreshes cache when new data is inserted.
• Supports expiration and TTL (Time-to-Live) for cached data.

Installation

To set up the project, follow these steps:

1. Clone the repository:

   git clone https://github.com/KhaledSaeed18/nodejs-backend-caching.git
   cd node-cache

2. Install dependencies:

   npm install

Usage

1. Run the Development Server

To start the development server, use:

npm run dev

This will start the server and automatically restart on file changes using nodemon.

2. Endpoints

• GET /users: Fetches user data with caching.

  Request URL:

  GET http://localhost:3000/api/users

• POST /users: Adds a new user to the mock data collection and refreshes the cache.

  Request URL:

  POST http://localhost:3000/api/users

  Request Body:

    {
      "id": 11,
      "name": "John Doe",
      "email": "johndoe@example.com",
      "age": 30,
      "role": "developer",
      "country": "USA"
    }

Project Structure

/src
    /cacheService.ts       // Caching logic using node-cache
    /mockData.ts           // Mock data for demonstration
    /routes.ts             // API routes for users
    /server.ts             // Server initialization
/package.json
/tsconfig.json

About node-cache

The node-cache package is an in-memory caching solution for Node.js applications. It provides fast and simple caching with features such as:

• Time-to-live (TTL) and expiration handling
• Ability to store different types of data (strings, objects, etc.)
• Automatic cleanup of expired cache entries
• Keys with individual TTL settings
• Event handling for expired keys

Key Functions

• set(key, value, [ttl]): Store a value with optional TTL
• get(key): Retrieve a value by key
• del(key): Delete a key from cache
• has(key): Check if key exists
• keys(): Get all existing keys
• getStats(): Retrieve cache statistics
• flushAll(): Clear entire cache
• close(): Clean up and shutdown the cache

Advanced Features

• mset(): Set multiple keys at once
• mget(): Get multiple keys at once
• mdel(): Delete multiple keys
• getTtl(): Get remaining TTL for a key

Events

• expired: Triggered when a key expires
• flush: Triggered when cache is cleared
• del: Triggered when a key is deleted

This caching solution is perfect for reducing database load and improving application response times.