harshxraj/multi-level-comment-system

Multi-Level Comment System

A social media platform API for handling posts and multi-level comments. This system allows users to create comments, reply to existing comments, and retrieve comments with pagination. The project is secured with JWT-based user authentication and includes rate limiting to ensure efficient usage.

Features

• User registration and authentication with JWT
• Create, reply to, and retrieve multi-level comments
• Pagination for retrieving comments
• Rate limiting to prevent abuse
• Dockerized setup for easy deployment
• Integration tests to validate functionality

Table of Contents

• Installation
• Usage
• API Endpoints
  • User Authentication
  • Create Comment
  • Reply to Existing Comment
  • Get Comments for a Post
  • Expand Parent-Level Comments with Pagination
• Database Schema
• Deployment
• Tests
• Contributing
• License

Installation

1. Clone the repository:

   git clone https://github.com/your-username/multi-level-comment-system.git
   cd multi-level-comment-system

2. Install dependencies:

   npm install

3. Set up environment variables:

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

   PORT=3000
   MONGO_URI=your_mongodb_uri
   JWT_SECRET=your_jwt_secret

4. Run the development server:

   npm start

5. To run in a Docker container:

   docker-compose up --build

Usage

After starting the server, you can interact with the API using tools like Postman or cURL. All endpoints are prefixed with /api.

API Endpoints

User Authentication

Register a New User

• Endpoint: /api/auth/register

• Method: POST

• Request Body:

  {
    "username": "johndoe",
    "email": "johndoe@example.com",
    "password": "password123"
  }
  

• Sample Response:

  {
    "message": "User registered successfully"
  }

Login

• Endpoint: /api/auth/login

• Method: POST

• Request Body:

  {
    "email": "johndoe@example.com",
    "password": "password123"
  }

• Sample Response:

  {
    "token": "your_jwt_token"
  }

Create Comment

• Endpoint: /api/posts/{postId}/comments

• Method: POST

• Headers:

  {
    "Authorization": "Bearer your_jwt_token"
  }

• Request Body:

  {
    "text": "This is a comment"
  }

• Sample Response:

  {
    "id": "64fa8f3b12345abc67890123",
    "text": "This is a comment",
    "createdAt": "2024-08-21T14:35:22.947Z",
    "postId": "64fa8f3b12345abc67890123",
    "userId": "64fa8f3b12345abc67890123",
    "parentCommentId": null
  }

Reply to Existing Comment

• Endpoint: /api/posts/{postId}/comments/{commentId}/reply

• Method: POST

• Headers:

  {
    "Authorization": "Bearer your_jwt_token"
  }

• Request Body:

  {
    "text": "This is a reply to a comment"
  }

• Sample Response:

  {
    "id": "64fa8f4c98765def12345678",
    "text": "This is a reply to a comment",
    "createdAt": "2024-08-21T14:36:44.123Z",
    "postId": "64fa8f3b12345abc67890123",
    "userId": "64fa8f3b12345abc67890123",
    "parentCommentId": "64fa8f3b12345abc67890123"
  }

Get Comments for a Post

• Endpoint: /api/posts/{postId}/comments

• Method: GET

• Query Parameters (Optional):

  • sortBy: Field to sort comments by (e.g., createdAt, repliesCount)
  • sortOrder: Sorting order (asc for ascending, desc for descending)

• Sample Response:

  [
    {
      "id": "64fa8f3b12345abc67890123",
      "text": "This is a comment",
      "createdAt": "2024-08-21T14:35:22.947Z",
      "postId": "64fa8f3b12345abc67890123",
      "parentCommentId": null,
      "replies": [
        {
          "id": "64fa8f4c98765def12345678",
          "text": "This is a reply to a comment",
          "createdAt": "2024-08-21T14:36:44.123Z"
        }
      ],
      "totalReplies": 1
    }
  ]

Expand Parent-Level Comments with Pagination

• Endpoint: /api/posts/{postId}/comments/{commentId}/expand

• Method: GET

• Query Parameters:

  • page: Page number (e.g., 1, 2)
  • pageSize: Number of comments per page (e.g., 10)

• Sample Response:

  [
    {
      "id": "64fa8f3b12345abc67890123",
      "text": "This is a nested comment",
      "createdAt": "2024-08-21T14:35:22.947Z",
      "postId": "64fa8f3b12345abc67890123",
      "parentCommentId": "64fa8f3b12345abc67890123",
      "replies": [],
      "totalReplies": 0
    }
  ]

Database Schema

Post Schema

const postSchema = new Schema({
  title: { type: String, required: true },
  content: { type: String, required: true },
  userId: { type: mongoose.Schema.Types.ObjectId, ref: 'User', required: true },
  createdAt: { type: Date, default: Date.now },
  updatedAt: { type: Date, default: Date.now },
  tags: [{ type: String }],
  likes: [{ type: mongoose.Schema.Types.ObjectId, ref: 'User' }],
  commentsCount: { type: Number, default: 0 },
});

Comment Schema

const commentSchema = new Schema({
  text: { type: String, required: true },
  postId: { type: mongoose.Schema.Types.ObjectId, ref: 'Post', required: true },
  userId: { type: mongoose.Schema.Types.ObjectId, ref: 'User', required: true },
  parentCommentId: { type: mongoose.Schema.Types.ObjectId, ref: 'Comment', default: null },
  createdAt: { type: Date, default: Date.now },
});

Deployment

To deploy the Dockerized application:

1. Build and run the Docker container:

   docker-compose up --build -d

2. The application will be available at http://localhost:3000.

3. To deploy on a hosting service like Heroku, follow their specific deployment guidelines for Docker.

Tests

Run the integration tests to validate the API functionality:

npm test

Contributing

Contributions are welcome! Please fork this repository, make your changes, and submit a pull request.

License

This project is licensed under the MIT License.

This README provides a comprehensive overview of the project, including installation instructions, details on the API endpoints, and sample responses. Make sure to replace placeholders like `your-username`, `your_mongodb_uri`, and `your_jwt_secret` with actual values.