📘 API Integration Project – README

🚀 Overview

This project is a simple API Integration assignment built using Node.js + Express. It fetches data from two public REST API endpoints, caches the response locally, and exposes clean API routes with filtering and detailed views.

This fulfills the requirements of the GLOBAL TREND – API Integration Internship Assignment.

---

⭐ Features

• Fetch data from JSONPlaceholder (Posts + Users)

• Cache responses locally (cache.json)

• API endpoints for:

  • Listing with filtering
  • Viewing details by ID

• Error handling for:

  • Network failure
  • Timeout
  • Malformed responses

• Simple, readable code structure

---

🛠 Tech Stack

• Node.js
• Express.js
• Axios
• File System (fs) for caching

---

📁 Project Structure

project/
│── src/
│   ├── server.js        # Entry point
│   ├── apiClient.js     # Fetch + error handling
│   └── routes.js        # Express routes
│── cache.json           # Cached API data
│── package.json
└── README.md

---

⚙️ Setup Instructions

1️⃣ Install dependencies

npm install

2️⃣ Start the server

npm start

Server runs at:

http://localhost:3000

---

🔗 API Endpoints

1️⃣ Get all posts (with filters)

GET /api/posts

Optional Filters

GET /api/posts?userId=1
GET /api/posts?title=qui

---

2️⃣ Get single post by ID

GET /api/posts/:id

Example:

GET /api/posts/5

---

3️⃣ Get all users

GET /api/users

---

4️⃣ Get single user by ID

GET /api/users/:id

---

5️⃣ Force refresh API (ignore cache)

GET /api/refresh

---

🧠 How Caching Works

1. When /posts or /users is requested:

   • If cache exists → return cached data
   • Else → fetch from API, save to cache.json, then return

2. When /refresh is called:

   • Always fetch fresh data
   • Overwrite old cache

This reduces API calls and speeds up responses.

---

🛡 Error Handling Includes

• Network failure fallback to cache
• Timeout handling for Axios
• Invalid/malformed API response
• Missing cache file scenario

---

📌 Endpoints Used (JSONPlaceholder)

• https://jsonplaceholder.typicode.com/posts
• https://jsonplaceholder.typicode.com/users

---

📝 Notes / Assumptions

• Caching is file-based for simplicity
• Only GET routes needed as per assignment
• No database required