worker links wip

worker_links_wip.js

// Set this in your worker's environment. wrangler.toml or cloudflare dashboard.
let secret = WORKERLINKS_SECRET;

addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request));
})

/**
 * Respond to the request
 * @param {Request} request
 */
async function handleRequest(request) {
  var key = new URL(request.url).pathname;
  var shorturl = new URL(request.url).origin + key;

  if (request.method == "PUT") {
    return await putLink(request.headers.get("Authorization"), shorturl, key, request.headers.get("URL"));
  } else if (request.method == "POST") {
    if (key != "/") {
      return new Response(
        JSON.stringify({
          "code": "405 Method Not Allowed",
          "message": "POST not valid for individual keys. Did you mean PUT?"
        }),
        {
          status: 405,
          headers: {
            "Content-Type": "application/json"
          }
        });
    }
    key = "/" + Math.random().toString(36).slice(5);
    shorturl = new URL(request.url).origin + key;
    return await putLink(request.headers.get("Authorization"), shorturl, key, request.headers.get("URL"));
  } else if (request.method == "GET" || request.method == "HEAD") {
    let url = await kv.get(key);
    if (url == null) {
      return new Response(
        JSON.stringify({
          "code": "404 Not Found",
          "message": "Key does not exist or has not propagated."
        }, null, 2),
          {
            status: 404,
            headers: {
              "Content-Type": "application/json"
            }
          })
    } else {
      return new Response(null, { status: 302, headers: { "Location": url } })
    }
    return new Response(
      JSON.stringify({
        "code": "500 Internal Server Error",
        "message": "An internal error ocurred while processing your request.",
        "hint": "method_didnt_return"
      }, null, 2),
      {
        status: 500,
        headers: {
          "Content-Type": "application/json"
        }
      });

  }
  return new Response(
    JSON.stringify({
      "code": "405 Method Not Allowed",
      "message": "Unsupported method. Please use one of GET, PUT, POST, DELETE, HEAD."
    }, null, 2),
    {
      status: 405,
      headers: {
        "Content-Type": "application/json"
      }
    });
}

function validateUrl(url) {
  // quick and dirty validation
  if (url == "") {
    return false;
  }
  try {
    new URL(url);
  } catch (TypeError) {
    return false;
  }
  return true;
}


async function putLink(givenSecret, shorturl, key, url) {
  if (givenSecret != secret) {
    return new Response(
      JSON.stringify({
        "code": "401 Unauthorized",
        "message": "Unauthorized."
      }, null, 2),
      {
        status: 401,
        headers: {
          "Content-Type": "application/json"
        }
      }
    )
  }

  if (url == null || !validateUrl(url)) {
    return new Response(
      JSON.stringify(
        {
          "code": "400 Bad Request",
          "message": "No valid URL given. Please set a 'URL' header."
        }, null, 2
      ),
      {
        status: 400,
        headers: {
          "Content-Type": "application/json"
        }
      }
    );
  }

  await kv.put(key, url);
  return new Response(
    JSON.stringify({
      "message": "URL created succesfully.",
      "key": key.substr(1),
      "shorturl": shorturl,
      "longurl": url
    }, null, 2), {
      status: 200,
      headers: {
        "Content-Type": "application/json"
      }
    })
}