How to expand shortened URLs using JavaScript or jQuery?

Other Questions JavaScript
1

Hey everyone! I’m trying to figure out a way to get the full version of a shortened URL using just JavaScript or jQuery. I can’t use Node.js because I’m on a basic hosting setup. Here’s what I’m aiming for:

function expandUrl(shortUrl) {
  // Magic happens here
  return longUrl;
}

I want to be able to pass in something like a bit.ly link and get back the original, unshortened URL. Has anyone done this before? What’s the best approach? I’m really stumped and could use some help. Thanks in advance!

2

I’ve encountered this challenge before, and unfortunately, there’s no straightforward way to expand shortened URLs using only client-side JavaScript. The core issue lies in the same-origin policy that browsers enforce for security reasons.

However, one option you might consider is using the CORS Anywhere service as a proxy. It allows you to bypass CORS restrictions. Here’s a basic implementation:

function expandUrl(shortUrl) {
  const corsProxy = 'https://cors-anywhere.herokuapp.com/';
  return fetch(corsProxy + shortUrl, { method: 'HEAD' })
    .then(response => response.url);
}

Be aware that this approach has limitations. It’s not suitable for production use due to rate limits and potential reliability issues. For a more robust solution, you’d need server-side code or a dedicated API service, as others have suggested.

3

I’ve tackled this problem before, and it’s trickier than it seems without server-side code. The main issue is that URL shorteners use HTTP redirects, which JavaScript can’t easily follow due to browser security restrictions.

One workaround I’ve used is to leverage a third-party API that handles the expansion for you. For example, you could try the Unshorten.me API. Here’s a basic implementation:

function expandUrl(shortUrl) {
  return fetch(`https://unshorten.me/json/${encodeURIComponent(shortUrl)}`)
    .then(response => response.json())
    .then(data => data.resolved_url);
}

Keep in mind this method has limitations. It relies on an external service, so you’re at the mercy of their uptime and rate limits. Also, some URL shorteners might block requests from these expansion services.

If you need a more robust solution, you might consider setting up a small proxy on your server to handle the redirects. But given your hosting constraints, the API approach is probably your best bet for now.

4

hey there! i’ve dealt with this before. sadly, pure js can’t expand shortened URLs easily cuz of browser security stuff. but you could try using a JSONP service like longurl.org API. it’s not perfect, but might work for ya. heres a quick example:

function expandUrl(shortUrl) {
var apiUrl = ‘http://api.longurl.org/v2/expand?url=’ + shortUrl + ‘&format=json&callback=?’;
return $.getJSON(apiUrl);
}