README.md

Task Manager REST API

A robust RESTful API for managing tasks with full CRUD operations, built with Node.js, Express.js, and MongoDB.

📋 Project Overview

This API allows you to create, read, update, and delete tasks with persistent storage. Each task contains an ID, title, status (pending/completed), and creation timestamp. The API includes input validation, error handling, and filtering capabilities.

🚀 Technologies Used

• Node.js - Runtime environment
• Express.js - Web framework
• MongoDB - NoSQL database
• Mongoose - MongoDB object modeling
• express-validator - Input validation middleware
• CORS - Cross-origin resource sharing
• dotenv - Environment variable management

📁 Project Structure

task-manager-api/
├── config/
│   └── db.js          # Database connection configuration
├── controllers/
│   └── taskController.js    # Request handlers and business logic
├── models/
│   └── Task.js              # MongoDB schema definition
├── routes/
│   └── tasks.js             # API route definitions
├── .env.example             # Environment variables template
├── .gitignore              # Git ignore rules
├── package.json            # Project dependencies and scripts
├── README.md               # Project documentation
└── server.js               # Main application entry point

🛠️ API Routes Documentation

Base URL

http://localhost:3000/tasks

Endpoints

Method	Endpoint	Description	Request Body
GET	/tasks	Get all tasks	None
GET	/tasks?status=pending	Get filtered tasks	None
GET	/tasks/:id	Get single task	None
POST	/tasks	Create new task	`{ "title": "string", "status": "pending
PUT	/tasks/:id	Update task	`{ "title": "string", "status": "pending
DELETE	/tasks/:id	Delete task	None

Query Parameters

• status (optional): Filter tasks by status (pending or completed)
• sortBy (optional): Sort field (default: created_at)
• order (optional): Sort order (asc or desc, default: desc)

Request/Response Examples

Create Task

Request:

POST /api/tasks
{
  "title": "Task-1",
  "status": "pending"
}

Response:

{
  "success": true,
  "data": {
    "_id": "686451eb2720807e376bc324",
    "title": "Task-1",
    "status": "pending",
    "created_at": "2025-07-01T21:23:55.915Z",
    "createdAt": "2025-07-01T21:23:55.918Z",
    "updatedAt": "2025-07-01T21:23:55.918Z",
    "__v": 0
  }
}

Get All Tasks

Request:

GET /tasks

Response:

{
  "success": true,
  "count": 2,
  "data": [
    {
      "_id": "686451eb2720807e376bc324",
        "title": "Task-1",
        "status": "pending",
        "created_at": "2025-07-01T21:23:55.915Z",
        "createdAt": "2025-07-01T21:23:55.918Z",
        "updatedAt": "2025-07-01T21:23:55.918Z",
        "__v": 0
    },
    {
        "_id": "6864044845dfef0184859988",
        "title": "Attend meeting",
        "status": "pending",
        "created_at": "2025-07-01T15:52:40.159Z",
        "createdAt": "2025-07-01T15:52:40.165Z",
        "updatedAt": "2025-07-01T15:52:40.165Z",
        "__v": 0
    }
  ]
}

Update Task

Request:

PUT /tasks/6864044845dfef0184859988
{
  "status": "completed"
}

Response:

{
  "success": true,
  "data": {
    "_id": "6864044845dfef0184859988",
    "title": "Attend meeting",
    "status": "completed",
    "created_at": "2025-07-01T15:52:40.159Z",
    "createdAt": "2025-07-01T15:52:40.165Z",
    "updatedAt": "2025-07-01T15:52:40.165Z",
    "__v": 0
  }
}

🏃‍♂️ Running Instructions

Prerequisites

• Node.js (v14 or higher)
• MongoDB (local installation or MongoDB Atlas)
• npm or yarn package manager

Installation Steps

1. Clone the repository:

   git clone <your-repo-url>
   cd task-manager-api

2. Install dependencies:

   npm install

3. Set up environment variables:

   cp .env.example .env

   Edit .env file with your configuration:

   MONGODB_URI= 
   PORT= 
   NODE_ENV= 

4. Start MongoDB:

   • For local MongoDB: mongod
   • For MongoDB Atlas: Use the connection string in MONGODB_URI

5. Run the application:

   Development mode (with auto-restart):

   npm run dev

   Production mode:

   npm start

6. Verify the API is running: Open browser or Postman and visit: http://localhost:3000

📮 Sample Postman Request Flows

Flow 1: Complete Task Management

1. Create Task: POST /tasks with body {"title": "Test Task"}
2. Get All Tasks: GET /tasks to see the created task
3. Update Task: PUT /tasks/{id} with body {"status": "completed"}
4. Filter Completed: GET /tasks?status=completed
5. Delete Task: DELETE /tasks/{id}

Flow 2: Error Handling Test

1. Invalid Create: POST /tasks with empty body (should return validation error)
2. Invalid ID: GET /tasks/invalid-id (should return format error)
3. Not Found: GET /tasks/65f123abc456def789012999 (should return 404)

🔧 .env File Details

Create a .env file in the root directory with the following variables:

# MongoDB connection string
# For local MongoDB:
MONGODB_URI=mongodb://localhost:27017/TaskManagerAPI

# For MongoDB Atlas:
# MONGODB_URI=your_mongodb_connection_string_here

# Server port (default: 3000)
PORT=3000

Environment Variables Explanation:

• MONGODB_URI: Database connection string
• PORT: Server port number

🚨 Error Handling

The API includes comprehensive error handling:

• 400 Bad Request: Invalid input data or malformed requests
• 404 Not Found: Resource doesn't exist
• 500 Internal Server Error: Server-side errors

Example error response:

{
  "success": false,
  "error": "Validation Error",
  "details": [
    {
      "msg": "Title is required",
      "param": "title",
      "location": "body"
    }
  ]
}

📝 Input Validation

• Title: Required, 1-100 characters, trimmed
• Status: Optional, must be 'pending' or 'completed'
• ID: Must be valid MongoDB ObjectId format

🔍 Features

• ✅ Full CRUD operations
• ✅ Input validation with detailed error messages
• ✅ MongoDB integration with Mongoose
• ✅ Task filtering by status
• ✅ Sorting capabilities
• ✅ CORS enabled
• ✅ Environment-based configuration
• ✅ Comprehensive error handling
• ✅ RESTful API design

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Commit your changes
4. Push to the branch
5. Create a Pull Request