Links are the bread and butter of Dub. Everything on Dub starts with a link. Whether you’re creating:
  • a handful of links for your marketing campaign
  • hundreds of links for your affiliate program
  • thousands of links, programmatically, for your SMS campaign
In this guide, we’ll cover the link model, how to create links, and more. The link model consists of the following properties:
PropertyDescriptionExample
idThe unique identifier of the link (prefixed with link_)link_eBKA4MT44XnI17hYLchkjUOd
urlThe destination URL of the linkhttps://dub.co/home
shortLinkThe shortened version of the link (including https)https://dub.link/claim
domainThe domain of the linkdub.link
keyThe short link slugclaim
For more advanced features like custom link previews, conversion tracking, and more, see the full list of properties below;
You can use the various Dub SDKs to programmatically manage your links. The url field, representing the destination URL, is the sole mandatory parameter required for the creation of a new short link. 
import { Dub } from "dub";

export const dub = new Dub({
  token: process.env.DUB_API_KEY,
});

const link = await dub.links.create({
  url: "https://google.com",
});
An existing link can be updated by providing the id to the update method. This method returns the updated link as a response. You can use either the linkId or an externalId prefixed with ext_ which is a unique identifier for the link in your own database to associate it with the link in Dub’s system. 
import { Dub } from "dub";

export const dub = new Dub({
  token: process.env.DUB_API_KEY,
});

const link = await dub.links.update("link_eBKA4MT44XnI17hYLchkjUOd", {
  url: "https://www.google.uk", // new URL
});
Upserting a link is a combination of creating and updating a link. If a link with the same URL already exists, return it (or update it if there are any changes). Otherwise, a new link will be created. This allows you to use the upsert method without the necessity of checking for the link’s existence beforehand. 
import { Dub } from "dub";

export const dub = new Dub({
  token: process.env.DUB_API_KEY,
});

const link = await dub.links.upsert({
  url: "https://google.com", // will always be the same short link
});