Task API

A beginner-friendly CRUD API built for the FlyRank Backend Internship Week 2 assignment. It manages an in-memory list of tasks with Express.js. Data is intentionally reset whenever the server restarts; no database is used.

Requirements

• Node.js 18 or newer
• npm

Installation

npm install

Run

npm start

The hand-built API runs at http://localhost:3000.

Endpoints

Method	Endpoint	Description	Success	Errors
GET	/	API information	200	—
GET	/health	Health check	200	—
GET	/tasks	List all tasks	200	—
GET	/tasks/:id	Get one task	200	404
POST	/tasks	Create a task	201	400
PUT	/tasks/:id	Update a task title and/or completion status	200	400, 404
DELETE	/tasks/:id	Delete a task	204	404
GET	/stats	Return total, done, and open counts	200	—
POST	/reset	Restore the three sample tasks	200	—
GET	/docs	Interactive Swagger UI documentation	200	—

Optional query parameters

• GET /tasks?done=true returns only completed tasks. Use done=false for open tasks.
• GET /tasks?search=milk searches task titles case-insensitively.
• GET /tasks?limit=2\&offset=2 returns a page of matching tasks.
• Filtering, search, and pagination can be combined.

Example curl requests

List tasks:

curl -i http://localhost:3000/tasks

Create a task:

curl -i -X POST http://localhost:3000/tasks \\
  -H "Content-Type: application/json" \\
  -d '{"title":"Buy milk"}'

Example response:

HTTP/1.1 201 Created
Content-Type: application/json; charset=utf-8

{"id":4,"title":"Buy milk","done":false}

Filter, search, and paginate:

curl -i "http://localhost:3000/tasks?done=false\&search=express\&limit=2\&offset=0"

Get statistics and reset the in-memory data:

curl -i http://localhost:3000/stats
curl -i -X POST http://localhost:3000/reset

Update a task:

curl -i -X PUT http://localhost:3000/tasks/4 \\
  -H "Content-Type: application/json" \\
  -d '{"done":true}'

Delete a task:

curl -i -X DELETE http://localhost:3000/tasks/4

Swagger UI

Open http://localhost:3000/docs while the server is running. Use Try it out to complete the full CRUD cycle and try the optional endpoints without curl.

The OpenAPI document is generated from the route comments with swagger-jsdoc when the server starts and is served through swagger-ui-express. The generated document is also saved as openapi.json.

Mortality experiment

The tasks are stored only in memory, so creating a task and restarting the server removes that task. This happens because there is no database or file persistence yet; the assignment uses this limitation to prepare for database work in Week 3.

AI vs me

Prompt used

Build a beginner-friendly JavaScript Node.js API using Express.js only. Use port 3001 and an in-memory array with three sample tasks containing numeric id, string title, and boolean done fields. Implement GET /, GET /health, GET /tasks, GET /tasks/:id, POST /tasks, PUT /tasks/:id, and DELETE /tasks/:id. POST must require a non-empty title, assign the next id, set done to false, and return 201. PUT must allow title and/or done updates, reject an empty or invalid body with 400, and return 404 for an unknown id. DELETE must return 204 with no body and 404 for an unknown id. Return JSON errors and keep the code beginner-friendly with no database, authentication, TypeScript, ORM, or unnecessary folders. Also include Swagger UI at /docs using swagger-ui-express and document the API with an OpenAPI file.

Three concrete differences found

1. The AI version combines the POST title validation messages, while the hand-built version distinguishes “Title is required” from “Title cannot be empty.”
2. The AI version uses a separate port, 3001, so it can be run beside the hand-built API for comparison.
3. The hand-built version includes the optional filtering, search, statistics, reset, pagination, and Swagger-jsdoc features; the quarantined AI version contains only the core Stage 0–6 CRUD API.

The AI version was run on port 3001 and tested with the Stage 4 CRUD requests. The hand-built version remained untouched while the AI version was reviewed.

Rematch result

The second prompt added the exact validation-message distinction and the requirement to keep the optional query and statistics endpoints. The hand-built version already satisfies those additional requirements, so no change was made to the hand-built code after the review.

Folder structure

task-api/
├── package.json
├── package-lock.json
├── index.js
├── openapi.json
├── README.md
├── ai-version/
│   └── index.js
└── screenshots/
    └── swagger.png

Validation and status codes

• New tasks require a non-empty title; invalid input returns 400.
• Updates must include title and/or done; empty or invalid input returns 400.
• Unknown task ids return 404 with a JSON error.
• Successful reads and updates return 200.
• Successful creation returns 201.
• Successful deletion returns 204 with no response body.