index.js

/**
 * Hash message
 * @param {string} message - data to hash
 * @param {string} digest - digest(MD5, SHA-1 SHA-256 SHA-384 SHA-512)
 */
const hashTo = async (message, digest = "SHA-512") => {
  const msgBuffer = new TextEncoder("utf-8").encode(message);
  const hashBuffer = await crypto.subtle.digest(digest, msgBuffer);
  const hashArray = Array.from(new Uint8Array(hashBuffer));
  const hashHex = hashArray
    .map(b => ("00" + b.toString(16)).slice(-2))
    .join("");
  return hashHex;
};

/**
 * Hash string from URL
 * @param {Event} event
 */
const handleRequest = async event => {
  const parsedUrl = new URL(event.request.url);
  const str = parsedUrl.pathname.replace("/", "");
  const result = {
    sha1: await hashTo(str, "SHA-1"),
    sha256: await hashTo(str, "SHA-256"),
    sha384: await hashTo(str, "SHA-384"),
    sha512: await hashTo(str, "SHA-512")
  };

  const responseInit = {
    headers: {
      "Content-Type": "application/json; charset=utf-8",
      "Access-Control-Allow-Origin": "*"
    }
  };

  return new Response(JSON.stringify(result), responseInit);
};

addEventListener("fetch", event => event.respondWith(handleRequest(event)));