I am building an open source, highly scalable, and low-costURL shortener with Cloudflare KV

By low-cost I mean, just $5 per month on Cloudflare worker and a free plan for basic requirement -

Idea

AtDaySchedule, we had many customer upvoted for a URL shortener feature with auto-expirable links to book an appointment instead sharing their original URL.

So, I decided to try Cloudflare for this project -

By leveraging Cloudflare KV's capabilities, the goal was to develop a solution that offered not onlyURL shortening but also customization options, analytics, and scalability, all while maintaining a significantly lower cost compared to our established services on AWS.

Features

• Expirable links usingcacheTtl option on KV
• Custom domain using Cloudflare for SaaS
• Analytics usingWorker analytics

API

I usedhono.dev by@yusukebe for API routing, and it's blazing fast and offers Cloudflare pages template to build Edge projects quickly.

Here is an example ofserver.ts from their docs -

import { Hono } from 'hono'const app = new Hono()app.get('/', (c) => c.text('Hono!'))export default app

Controller

The/links API is all I need to create, update and manage the short links.

const links = new Hono<{ Bindings: Bindings }>();links.post(  '/',  validator('json', (value, c) => {    const parsed = linkSchema.safeParse(value);    if (!parsed.success) {      return c.json(parsed, 400);    }    return parsed.data as ShortLink;  }),  async (ctx) => {    const data = ctx.req.valid('json');    // Set expire_at if given, or fallback to 1 month expiry    const expireAt = data.expire_at      ? dayjs(data.expire_at).unix()      : dayjs().add(1, 'month').unix();    if (expireAt <= dayjs().unix()) {      return ctx.json(        { message: 'The expire_at must be greater then current date time' },        400      );    }    let key = data.key || nanoid(7);    let exists = await ctx.env.SHORTLINKS.get(key);    while (exists) {      key = nanoid(7);      exists = await ctx.env.SHORTLINKS.get(key);    }    await ctx.env.SHORTLINKS.put(key, JSON.stringify(data), {      expiration: expireAt,    });    return ctx.json(      { ...data, key: key, short_url: `https://idm.in/${key}` },      200    );  });

Code explanations -

This code isPOST request to create short links. Here's a breakdown of the code to explain what all I am doing:

1. const links = new Hono<{ Bindings: Bindings }>(): It creates an instance of the Hono object.

2. Validation with zod - Thevalidator('json', (value, c) => {...}): function is used as a middleware for validating the incoming JSON payload defined inlinkSchema.

3. Set expiration: Checks if an expiry date is provided in the payload. If not, it sets an expiry date one month from the current date and time.

4. Generates a unique key for the link usingnanoid(7) or uses the provided key from the payload if available.

5. Stores the link data (converted to a JSON string) in the Cloudflare KV (SHORTLINKS) with an expiration time based on the calculated expiry date.

Demo

The demo is available onIDM, it's free to use and open-sourced on Github tobuild your own custom URL shortener.

You can clone the repo to deploy on your Cloudflare account.

Star the repository on Github to show your support :-)