@techmely/utils/id.js

Collection of helpful JavaScript / TypeScript utils

'use strict';

var crypto = require('crypto');

var POOL_SIZE_MULTIPLIER = 128;
var pool;
var poolOffset;
function fillPool(bytes) {
  if (!pool || pool.length < bytes) {
    pool = Buffer.allocUnsafe(bytes * POOL_SIZE_MULTIPLIER);
    crypto.webcrypto.getRandomValues(pool);
    poolOffset = 0;
  } else if (poolOffset + bytes > pool.length) {
    crypto.webcrypto.getRandomValues(pool);
    poolOffset = 0;
  }
  poolOffset += bytes;
}
function random(bytes) {
  fillPool(bytes -= 0);
  return pool.subarray(poolOffset - bytes, poolOffset);
}
function customRandom(alphabet, defaultSize, getRandom) {
  let mask = (2 << 31 - Math.clz32(alphabet.length - 1 | 1)) - 1;
  let step = Math.ceil(1.6 * mask * defaultSize / alphabet.length);
  return (size = defaultSize) => {
    let id = "";
    while (true) {
      let bytes = getRandom(step);
      let i = step;
      while (i--) {
        id += alphabet[bytes[i] & mask] || "";
        if (id.length === size)
          return id;
      }
    }
  };
}
function customAlphabet(alphabet, size = 21) {
  return customRandom(alphabet, size, random);
}

// src/id.ts
var generateId = customAlphabet(
  "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
);
var DEFAULT_PREFIX_ID_LENGTH = 22;
function generatePrefixId(prefix = "key", length = DEFAULT_PREFIX_ID_LENGTH) {
  return `${prefix}_${generateId(length)}`;
}

exports.DEFAULT_PREFIX_ID_LENGTH = DEFAULT_PREFIX_ID_LENGTH;
exports.generateId = generateId;
exports.generatePrefixId = generatePrefixId;