Deno twtxt hash calc

twtxt-hash.test.ts

import { encode } from "https://deno.land/std@0.163.0/encoding/base32.ts";
import { blake2b } from "https://esm.sh/blakejs@1.2.1";
import { DateTime } from "https://esm.sh/luxon@3.1.0";
import { assertEquals } from "https://deno.land/std@0.163.0/testing/asserts.ts";

function base32(payload: Uint8Array) {
  return encode(payload).replace(/=/g, "").toLowerCase();
}
function blake2b256(payload: string) {
  return blake2b(payload, undefined, 32);
}
function formatRFC3339(text: string) {
  return DateTime.fromISO(text, { setZone: true, zone: "utc" })
    .toFormat("yyyy-MM-dd'T'HH:mm:ssZZ")
    .replace(/\+00:00$/, "Z");
}

const twt = {
  url: "https://twtxt.net/user/prologic/twtxt.txt",
  hash: "o6dsrga",
  created: "2020-07-18T12:39:52Z",
  content: "Hello World! 😊",
};

const created = formatRFC3339(twt.created);
const payload = [twt.url, created, twt.content].join("\n");
const hash = base32(blake2b256(payload)).slice(-7);

Deno.test("hash", () => {
  assertEquals(hash, twt.hash);
});