URL Shortener Service

Project link: https://roadmap.sh/projects/url-shortening-service

A RESTful URL shortening service built with Node.js, Express, and MongoDB. Provides features similar to TinyURL or Bitly: create, retrieve, update, delete, and track short URLs.

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🌟 Features

• Shorten URLs: Generate compact URLs using SHA256 + Base62 encoding.
• Retrieve original URLs by short code.
• Update URLs for existing short codes.
• Delete URLs from the database.
• Track statistics: Access count, creation date, and last update.

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🧪 API Testing with Postman

I used Postman to test all APIs, including creating, retrieving, updating, deleting URLs, and fetching statistics. The testing flows included chaining requests (e.g., creating a URL, retrieving it, updating it, then checking stats) to ensure end-to-end correctness. You can import Postman collections to quickly replicate these API requests and test the service locally.

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📂 Folder Structure

Backend/
├── controllers/
│   └── controllers.js      # Handles all request logic
├── models/
│   └── data.js             # Mongoose schema for URL documents
├── routes/
│   └── urlshort_route.js   # Defines all API endpoints
├── .env                    # MongoDB credentials & environment variables
├── server.js               # Express app entry point
├── package.json
└── package-lock.json

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⚙️ Environment Variables

Create a .env file in Backend/:

MONGO_URI=your_mongodb_connection_string
PORT=3001

Important: Keep .env in .gitignore to prevent exposing your database credentials.

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💻 Installation

1. Clone the repository:

git clone https://github.com/YourUsername/URL_Shortner_Service.git
cd URL_Shortner_Service/Backend

2. Install dependencies:

npm install

3. Start the server:

node server.js

Server runs at: http://localhost:3001

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🛣️ API Endpoints

1️⃣ Create Short URL

POST /shorten/

Body:

{
  "url": "https://example.com"
}

Response:

{
  "id": 1,
  "url": "https://example.com",
  "shortCode": "b2a1",
  "accessCount": 0,
  "createdAt": "2026-03-14T00:00:00Z",
  "updatedAt": "2026-03-14T00:00:00Z"
}

Curl Example:

curl -X POST http://localhost:3001/shorten/ \
-H "Content-Type: application/json" \
-d '{"url":"https://example.com"}'

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2️⃣ Retrieve Original URL

GET /shorten/:url

Params: url = short code

Response:

{
  "url": "https://example.com"
}

Curl Example:

curl http://localhost:3001/shorten/b2a1

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3️⃣ Update Short URL

PUT /shorten/:url

Params: url = short code

Body:

{
  "url": "https://new-url.com"
}

Response:

{
  "message": "URL updated successfully"
}

Curl Example:

curl -X PUT http://localhost:3001/shorten/b2a1 \
-H "Content-Type: application/json" \
-d '{"url":"https://new-url.com"}'

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4️⃣ Delete Short URL

DELETE /shorten/:url

Params: url = short code

Response: 204 No Content on success, 404 Not Found if not exists

Curl Example:

curl -X DELETE http://localhost:3001/shorten/b2a1

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5️⃣ Get URL Statistics

GET /shorten/:url/stats

Params: url = short code

Response:

{
  "id": 1,
  "url": "https://example.com",
  "shortCode": "b2a1",
  "accessCount": 5,
  "createdAt": "2026-03-14T00:00:00Z",
  "updatedAt": "2026-03-14T00:00:00Z"
}

Curl Example:

curl http://localhost:3001/shorten/b2a1/stats

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🧠 How It Works

• Hashing + Base62: The original URL is hashed using SHA256. The first 8 characters are converted to an integer, then encoded in Base62 to generate a unique short code.

• Database Storage: Each URL document stores:

  • id: Sequential identifier
  • url: Original URL
  • shortCode: Encoded short URL
  • accessCount: Number of times retrieved
  • createdAt / updatedAt: Timestamps

Controller Functions:

• createshorturlcontroller: Creates new short URLs
• retrieveoriginalurlcontroller: Retrieves original URL
• updateshorturlcontroller: Updates a URL
• deleteshorturlcontroller: Deletes a URL
• geturlstatscontroller: Returns statistics

RESTful Routes:

Method	Route	Action
POST	/shorten/	create
GET	/shorten/:url	retrieve
GET	/shorten/:url/stats	stats
PUT	/shorten/:url	update
DELETE	/shorten/:url	delete

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📈 Project Diagram

[Client] --> POST /shorten --> [Controller] --> [MongoDB]
[Client] --> GET /shorten/:url --> [Controller] --> [MongoDB] --> returns original URL
[Client] --> PUT /shorten/:url --> [Controller] --> updates DB
[Client] --> DELETE /shorten/:url --> [Controller] --> deletes from DB
[Client] --> GET /shorten/:url/stats --> [Controller] --> DB stats

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🔧 Tech Stack

• Node.js + Express
• MongoDB + Mongoose
• dotenv for environment variables
• Base62 encoding for short URLs
• RESTful API design

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✅ Notes

• Duplicate URLs generate the same short code (deterministic).
• Access counts are incremented every retrieval.
• Fully modular: controllers, routes, and models are separated.