| 1 | const crypto = require('crypto') |
| 2 | |
| 3 | /** |
| 4 | * Generate a cryptographically secure random number in the [0,1[ range |
| 5 | * |
| 6 | * @returns |
| 7 | */ |
| 8 | function secureRandom () { |
| 9 | return crypto.randomBytes(4).readUInt32LE() / 0x100000000 |
| 10 | } |
| 11 | |
| 12 | /** |
| 13 | * @param max |
| 14 | * @param min |
| 15 | */ |
| 16 | function generateRandomInteger (max, min = 0) { |
| 17 | if (max < 0) { |
| 18 | throw new RangeError('Invalid interval') |
| 19 | } |
| 20 | max = Math.floor(max) |
| 21 | if (min) { |
| 22 | if (max < min || min < 0) { |
| 23 | throw new RangeError('Invalid interval') |
| 24 | } |
| 25 | min = Math.ceil(min) |
| 26 | return Math.floor(secureRandom() * (max - min + 1)) + min |
| 27 | } |
| 28 | return Math.floor(secureRandom() * (max + 1)) |
| 29 | } |
| 30 | |
| 31 | /** |
| 32 | * @param ms |
| 33 | */ |
| 34 | async function sleep (ms) { |
| 35 | return new Promise(resolve => setTimeout(resolve, ms)) |
| 36 | } |
| 37 | |
| 38 | const LIST_FORMATTER = new Intl.ListFormat('en-US', { |
| 39 | style: 'long', |
| 40 | type: 'conjunction' |
| 41 | }) |
| 42 | |
| 43 | module.exports = { generateRandomInteger, sleep, secureRandom, LIST_FORMATTER } |