short_url.js

import { Router } from "itty-router";

const router = Router();

router.get("/", async (req, env) => {
  return new Response("Hello Workers", {
    status: 200,
  });
});

/* new short example json
{
  url: "https://tonypepe.com",
  len: 3,
}
*/
router.post("/new", async (req, env) => {
  const body = await req.json();
  console.log(JSON.stringify(body));
  var { url, len } = body;
  if (url == undefined) return f00("");
  if (!isValidHttpUrl(url)) return f00("URL is not valid");
  if (len == undefined) len = 5;
  if (len < 4) return f00("Lenght must be at least 4");
  var s = getRandomString(len);
  while ((await env.URLS.get(s)) != undefined) {
    len++;
    s = getRandomString(len);
  }
  await env.URLS.put(s, url);
  return new Response(s);
});

router.get("/:path", async (req, env) => {
  const { params } = req;
  const url = await env.URLS.get(params.path.toLowerCase());
  if (url == undefined) return new Response("NOT FOUND", { status: 404 });
  const response = new Response("", { status: 303 });
  response.headers.append("Location", url);
  return response;
});

router.get("*", async (req, env) => {
  return new Response("404", { status: 404 });
});

export default {
  fetch: router.handle,
};

const f00 = (msg) => new Response(msg ? msg : "BAD REQUEST", { status: 400 });

const getRandomInt = (max) => Math.floor(Math.random() * max);

function isValidHttpUrl(string) {
  let url;
  try {
    url = new URL(string);
  } catch (_) {
    return false;
  }
  return url.protocol === "http:" || url.protocol === "https:";
}

function getRandomString(len) {
  var s = "";
  for (let i = 0; i < len; i++) {
    s += String.fromCharCode(getRandomInt(26) + 97);
  }
  return s;
}