@thi.ng/ksuid/ulid.js

Configurable K-sortable unique IDs, ULIDs, binary & base-N encoded, 32/48/64bit time resolutions

import { BASE32_CROCKFORD } from "@thi.ng/base-n/32";
import { AKSUID } from "./aksuid.js";
class ULID extends AKSUID {
  constructor(opts) {
    super(6, {
      epoch: 0,
      bytes: 10,
      base: BASE32_CROCKFORD,
      ...opts
    });
  }
  timeOnlyBinary(epoch = Date.now()) {
    const buf = new Uint8Array(this.size);
    const t = this.ensureTime(epoch - this.epoch);
    const h = t / 4294967296 >>> 0;
    const l = (t & 4294967295) >>> 0;
    buf.set([
      h >> 8 & 255,
      h & 255,
      l >>> 24,
      l >> 16 & 255,
      l >> 8 & 255,
      l & 255
    ]);
    return buf;
  }
  parse(id) {
    const buf = new Uint8Array(this.size);
    this.base.decodeBytes(id, buf);
    return {
      epoch: (buf[0] << 8 | buf[1]) * 4294967296 + this.u32(buf, 2) + this.epoch,
      id: buf.slice(6)
    };
  }
}
const defULID = (opts) => new ULID(opts);
export {
  ULID,
  defULID
};