cf validate sas

export default {
  async fetch(request, env, ctx) {
    const cacheUrl = new URL(request.url);

    const response = await fetch(request.url, { method: 'HEAD' })

    async function gatherResponse(response) {
      return response.status;
    }

    const result = await gatherResponse(response);

    if (result != "200") {
      return new Response("Unauthorised", { status: 401 });
    }

    const urlWithoutQueryParams = request.url.replace(request.search, '');
    const cacheKey = new Request(urlWithoutQueryParams, request);
    const cache = caches.default;

    let cResponse = await cache.match(cacheKey);
    if (!cResponse) {
      console.log(
        `Response for request url: ${request.url} not present in cache. Fetching and caching request.`
      );
      // If not in cache, get it from origin
      cResponse = await fetch(request);

      // Must use Response constructor to inherit all of response's fields
      cResponse = new Response(response.body, response);

      // Any changes made to the response here will be reflected in the cached value
      response.headers.append("Cache-Control", "s-maxage=86400");

      ctx.waitUntil(cache.put(cacheKey, response.clone()));
    } else {
      console.log(`Cache hit for: ${request.url}.`);
    }

    return cResponse;

  }
}