Aggregate requests

const handler: ExportedHandler = {
  async fetch(request: Request) {
    /**
     * someHost is set up to return JSON responses
     * Replace url1 and url2 with the hosts you wish to send requests to
     * @param {string} url the URL to send the request to
     */
    const someHost = "https://examples.cloudflareworkers.com/demos";
    const url1 = someHost + "/requests/json";
    const url2 = someHost + "/requests/json";
    const type = "application/json;charset=UTF-8";

    /**
     * gatherResponse awaits and returns a response body as a string.
     * Use await gatherResponse(..) in an async function to get the response body
     * @param {Response} response
     */
    async function gatherResponse(response) {
      const { headers } = response;
      const contentType = headers.get("content-type") || "";
      if (contentType.includes("application/json")) {
        return JSON.stringify(await response.json());
      } else if (contentType.includes("application/text")) {
        return response.text();
      } else if (contentType.includes("text/html")) {
        return response.text();
      } else {
        return response.text();
      }
    }

    const init = {
      headers: {
        "content-type": type,
      },
    };

    const responses = await Promise.all([fetch(url1, init), fetch(url2, init)]);
    const results = await Promise.all([
      gatherResponse(responses[0]),
      gatherResponse(responses[1]),
    ]);
    return new Response(results.join(), init);
  },
};
export default handler;