English | Vietnamese |
Link shortener built with Node.js + Express, data stored in SQLite. No separate database server needed.
- Shorten a long link, or set your own short code, for example
/khuyen-mai. - Set a link expiry: 1 day, 7 days, 30 days, 1 year.
- Count clicks and view daily clicks for the last 30 days.
- Create a QR code for each link, view and download it as SVG.
- Delete a link.
- Each browser only sees and manages its own links.
- Only accepts
http:///https://links, limits links created per minute per IP. - Interface in Vietnamese and English.
Measured on a dev machine (Windows, Node 22, single process) with npm run bench:
| Scenario | Speed | Errors | Latency p50 / p99 |
|---|---|---|---|
Redirect GET /:code |
3000 req/s for 30 seconds | 0 | 6 ms / 44 ms |
Create link POST /api/shorten |
~3000 req/s for 10 seconds | 0 | 15 ms / 112 ms |
Peak RAM during the test: ~82 MB (target under 200 MB).
Why it is fast and uses little RAM:
- SQLite runs in WAL mode inside the Node process. Reading one link takes about 2 µs, with no network connection like Redis / MongoDB.
- Data lives on disk, not in RAM, so RAM does not grow with the number of links. SQLite page cache is limited to 16 MB.
- Clicks are batched and written once per second, instead of writing to disk on every click.
- Link creation requests arriving at the same time are written in one transaction.
npm startlimits the Node heap to 128 MB.
Requirement: Node.js 20 or later.
npm install
copy .env.example .env # then change BASE_URL to your domain
npm start # production
npm run dev # development, restarts automatically when code changes
Open in browser: http://localhost:3000
| Variable | Default | Meaning |
|---|---|---|
PORT |
3000 |
Port the server runs on |
BASE_URL |
http://localhost:PORT |
Public address, used to build short links |
DB_PATH |
data/urls.db |
SQLite database file (created automatically) |
RATE_LIMIT_PER_MIN |
30 |
Max links one IP can create per minute |
TRUST_PROXY |
(empty) | Set to 1 if behind nginx / Cloudflare to get the real IP |
npm test
Load test (start the server first, raise the creation limit to test link creation):
set RATE_LIMIT_PER_MIN=100000000 && npm start
npm run bench -- --rate 3000 --duration 30
shorturl/
├── config/
│ ├── index.js # Read environment variables
│ └── db.js # Open SQLite, tune performance, create tables
├── models/
│ └── Url.js # Data queries, batch clicks and batch creation
├── routes/
│ └── url.js # API and redirect routes
├── public/ # Frontend (index.html, styles.css, script.js)
├── scripts/bench.js # Load test with autocannon
├── test/api.test.js # API tests
└── server.js # Start the server
| Method | Path | Description |
|---|---|---|
POST |
/api/shorten |
Body { "originalUrl": "...", "customCode"?: "...", "expiresInDays"?: 7 }. Returns 201 on create, 200 if already shortened before, 409 if the custom code is taken. |
GET |
/api/urls?limit=20&offset=0 |
Your link list: { items, hasMore } |
GET |
/api/urls/:code/stats |
Link info and daily clicks for 30 days |
GET |
/api/urls/:code/qr |
QR code (SVG) |
DELETE |
/api/urls/:code |
Delete a link |
GET |
/:code |
Redirect to the original link (404 if not found, 410 if expired) |
Each link looks like: { urlCode, shortUrl, originalUrl, clicks, createdAt, expiresAt }.
- No account: the browser gets an anonymous cookie. If you clear cookies or use another browser, you will not see the history again (the links still work).
- When stopping the server with Ctrl+C, pending clicks are saved before exit. If the server is killed abruptly, up to 1 second of clicks may be lost.
- Backup: copy the files in the
data/folder.