mirror of
https://gitee.com/onvia/ccc-tnt-psd2ui
synced 2024-12-27 12:07:45 +00:00
36 lines
976 B
JavaScript
36 lines
976 B
JavaScript
import crypto from 'crypto'
|
|
import { urlAlphabet } from '../url-alphabet/index.js'
|
|
let random = bytes =>
|
|
new Promise((resolve, reject) => {
|
|
crypto.randomFill(Buffer.allocUnsafe(bytes), (err, buf) => {
|
|
if (err) {
|
|
reject(err)
|
|
} else {
|
|
resolve(buf)
|
|
}
|
|
})
|
|
})
|
|
let customAlphabet = (alphabet, defaultSize = 21) => {
|
|
let mask = (2 << (31 - Math.clz32((alphabet.length - 1) | 1))) - 1
|
|
let step = Math.ceil((1.6 * mask * defaultSize) / alphabet.length)
|
|
let tick = (id, size = defaultSize) =>
|
|
random(step).then(bytes => {
|
|
let i = step
|
|
while (i--) {
|
|
id += alphabet[bytes[i] & mask] || ''
|
|
if (id.length === size) return id
|
|
}
|
|
return tick(id, size)
|
|
})
|
|
return size => tick('', size)
|
|
}
|
|
let nanoid = (size = 21) =>
|
|
random(size).then(bytes => {
|
|
let id = ''
|
|
while (size--) {
|
|
id += urlAlphabet[bytes[size] & 63]
|
|
}
|
|
return id
|
|
})
|
|
export { nanoid, customAlphabet, random }
|