How to generate unique ID with node.js

Question

function generate(count) {
    var founded = false,
        _sym = \'abcdefghijklmnopqrstuvwxyz1234567890\',
        str = \'\';
    while(!founded) {
        for(va         


        

Answer 1

More easy and without addition modules

Math.random().toString(26).slice(2)

Answer 2

to install uuid

npm install --save uuid

uuid is updated and the old import

const uuid= require('uuid/v4');

is not working and we should now use this import

const {v4:uuid} = require('uuid');

and for using it use as a funciton like this

const  createdPlace = {
    id: uuid(),
    title,
    description,
    location:coordinates,
    address,
    creator
  };

Answer 3

The fastest possible way to create random 32-char string in Node is by using native crypto module:

const crypto = require("crypto");

const id = crypto.randomBytes(16).toString("hex");

console.log(id); // => f9b327e70bbcf42494ccb28b2d98e00e

Answer 4

I am using the following and it is working fine plus without any third-party dependencies.

const {
  randomBytes
} = require('crypto');

const uid = Math.random().toString(36).slice(2) + randomBytes(8).toString('hex') + new Date().getTime();

Answer 5

Extending from YaroslavGaponov's answer, the simplest implementation is just using Math.random().

Math.random()

The chances of fractions being the same in a real space [0, 1] is theoratically 0 and approximately close to 0 for a default length of 16 decimals in node.js. And this implementation should also reduce arithmetic overflows as no operations are performed. Also, it is more memory efficient compared to a string as Decimals occupy less memory than strings.

I call this the "Chong-Fractional-Unique-ID".

Wrote code to generate 1,000,000 Math.random() numbers and could not find any duplicates (at least for default decimal points of 16). See code below (please provide feedback if any):

random_numbers = [] 
for (i = 0; i < 1000000; i++) { 
   random_numbers.push(Math.random()) 
   //random_numbers.push(Math.random().toFixed(13)) //depends decimals default 16 
} 

if (i === 1000000) { 
   console.log("Before checking duplicate") 
   console.log(random_numbers.length) 
   console.log("After checking duplicate") 
   random_set = new Set(random_numbers) 
   console.log([...random_set].length) // length is still the same
} 

Answer 6

node-uuid is deprecated so please use uuid

npm install uuid --save
// Generate a v1 UUID (time-based) 
const uuidV1 = require('uuid/v1');
uuidV1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a' 

// Generate a v4 UUID (random) 
const uuidV4 = require('uuid/v4');
uuidV4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1' 

Npm link