Todo Server API

A minimal backend API for task management (TODO application) built with NestJS, TypeORM, and SQLite.

Features

• ✅ Create tasks with text and status
• ✅ Update task status (in progress → completed)
• ✅ Delete tasks
• ✅ Get all tasks with optional status filtering
• ✅ Get single task by ID
• ✅ SQLite database storage
• ✅ Docker containerization
• ✅ Swagger API documentation
• ✅ Input validation and error handling

Technologies Used

• Backend: NestJS (Node.js framework)
• Database: SQLite with TypeORM
• Validation: class-validator, class-transformer
• Documentation: Swagger/OpenAPI
• Containerization: Docker

Quick Start

Prerequisites

• Docker installed on your machine

Running with Docker

1. Clone the repository
2. Build and run the Docker container:

docker build -t todo-server .
docker run --name todo-server -p 3000:3000 todo-server

The API will be available at http://localhost:3000

Running Locally

1. Install dependencies:

npm install

2. Start the development server:

npm run start:dev

3. For production build:

npm run build
npm run start:prod

API Endpoints

Base URL: http://localhost:3000/api

Method	Endpoint	Description
GET	/tasks	Get all tasks (with optional status filter)
GET	/tasks/:id	Get task by ID
POST	/tasks	Create a new task
PATCH	/tasks/:id/status	Update task status
DELETE	/tasks/:id	Delete task

API Examples

Create a Task

POST /api/tasks
Content-Type: application/json

{
  "text": "Complete the project documentation",
  "status": "in_progress"  // optional, defaults to "in_progress"
}

Response:

{
  "id": 1,
  "text": "Complete the project documentation",
  "status": "in_progress",
  "createdAt": "2024-01-15T10:30:00Z",
  "updatedAt": "2024-01-15T10:30:00Z"
}

Get All Tasks

GET /api/tasks

With status filter:

GET /api/tasks?status=completed

Response:

[
  {
    "id": 1,
    "text": "Complete the project documentation",
    "status": "in_progress",
    "createdAt": "2024-01-15T10:30:00Z",
    "updatedAt": "2024-01-15T10:30:00Z"
  }
]

Get Task by ID

GET /api/tasks/1

Update Task Status

PATCH /api/tasks/1/status
Content-Type: application/json

{
  "status": "completed"
}

Delete Task

DELETE /api/tasks/1

Task Status Values

• in_progress - Task is currently being worked on
• completed - Task has been finished

API Documentation

Once the server is running, you can access the interactive Swagger documentation at: http://localhost:3000/api/docs

Database

The application uses SQLite database stored in the db/todo.db file. The database is automatically created when the application starts.

Task Schema

CREATE TABLE tasks (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  text VARCHAR(500) NOT NULL,
  status VARCHAR(20) DEFAULT 'in_progress',
  createdAt DATETIME DEFAULT CURRENT_TIMESTAMP,
  updatedAt DATETIME DEFAULT CURRENT_TIMESTAMP
);

Error Handling

The API provides comprehensive error handling with appropriate HTTP status codes:

• 400 Bad Request - Invalid input data or parameters
• 404 Not Found - Task not found
• 500 Internal Server Error - Server errors

All error responses follow a consistent format:

{
  "statusCode": 400,
  "message": "Validation failed",
  "error": "Bad Request"
}

Development

Available Scripts

• npm run start - Start the application
• npm run start:dev - Start in development mode with hot reload
• npm run start:prod - Start in production mode
• npm run build - Build the application
• npm run test - Run tests
• npm run lint - Run ESLint
• npm run format - Format code with Prettier

Project Structure

src/
├── config/           # Configuration files
├── modules/
│   └── tasks/       # Task module
│       ├── dto/     # Data Transfer Objects
│       ├── entities/ # Database entities
│       ├── types/   # TypeScript types
│       ├── tasks.controller.ts
│       ├── tasks.service.ts
│       └── tasks.module.ts
├── app.module.ts    # Root module
└── main.ts         # Application entry point