1const urlSafeCharset = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
2
3export const randomUrlSafeBytes = (noBytes: number): string => {
4  const maxUnbiased = 256 - (256 % urlSafeCharset.length) // 248 for 62 chars
5  const result: string[] = []
6  while (result.length < noBytes) {
7    const buf = new Uint8Array(noBytes - result.length)
8    crypto.getRandomValues(buf)
9    for (const v of buf) {
10      if (v < maxUnbiased && result.length < noBytes) result.push(urlSafeCharset[v % urlSafeCharset.length])
11    }
12  }
13  return result.join('')
14}
15