Generate random string in JavaScript (for a Discord bot)

Question

So, I'm looking to create a password generator function in discord.js, and I'd like to include [a-z][A-Z][0-9], whilst all being optional (I'd like for the user to be able to determine what to include in the password, for example whether they want lower and uppercase or only one). I've been trying to figure this out for a bit now and can't quite get it right (I'm pretty new to all this).

This is what I have so far:

if (message.content === `${prefix}pwgen`) {
        const random = (length = 8) => {
            
            let chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
        
            
            let str = '';
            for (let i = 0; i < length; i++) {
                str += chars.charAt(Math.floor(Math.random() * chars.length));
            }
        
            return str;
        
        };

This is some code I got from https://attacomsian.com/blog/javascript-generate-random-string but obviously, here, he uses console.log to get results from the block of code, but here I'd like to be able to have the user send a number on Discord so the bot generates a random string of that length, and then have the bot return it in Discord. How can I do this? Thanks!

Send a message with Discord.js

Theraot
– Theraot

2020-10-27 21:03:36 +00:00
Commented Oct 27, 2020 at 21:03 — Theraot
– Theraot, Commented Oct 27, 2020 at 21:03

jvda · Accepted Answer · 2020-10-27 22:14:18Z

3

I would like to add an alternative solution that does not use Math.random to get the random number. Using the crypto module should provide a better degree of randomness:

function genPassword (length = 14) {
  var randChars = Array(length).fill().map(getRandomChar)
  var pw = randChars.join('')
  return pw
}

function getRandomChar () {
  var crypt = window.crypto || window.msCrypto
  var target = new Uint8Array(1)
  var randNr = crypt.getRandomValues(target)
  var sevenBitRandNr = randNr >> 1
  if (sevenBitRandNr < 48
     || sevenBitRandNr >= 122
     || (sevenBitRandNr >= 58 && sevenBitRandNr <= 64)
     || (sevenBitRandNr >=91 && sevenBitRandNr <= 96)) {
    return getRandomChar()
  }
  return String.fromCharCode(sevenBitRandNr)
}

console.log(genPassword(20))

This does provide upper- and lowercase as well as numbers.

edited Oct 27, 2020 at 22:14

answered Oct 27, 2020 at 21:59

jvda

3162 silver badges7 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Iyashi Over a year ago

Definitely better than my primitive solution :p

jvda Over a year ago

I think your approach still needs to be mentioned in this context! Although the crypto module is widely supported nowadays, there are still browser that dont support it.

Iyashi · Accepted Answer · 2020-10-27 21:31:01Z

0

Not the perfect solution, but should work like a charm.

NOTICE: This does not include uppercase characters.

function generate (count = 20) {
  let password = ''
  while (password.length < count) {
    password += Math.random().toString(36).substr(2)
  }
  return password.substr(0, count)
}

console.log(generate(10), generate(20), generate(15))

edited Oct 27, 2020 at 21:31

answered Oct 27, 2020 at 21:21

Iyashi

5821 gold badge4 silver badges24 bronze badges

3 Comments

swabfu Over a year ago

Hm, alright, thanks! So now, I should be able to do: message.channel.send (`Your generated password is ${password}); Right? Or am I doing something wrong?

Iyashi Over a year ago

Yes, this code works as it is. I changed it to an executable, so you can see

swabfu Over a year ago

Works perfectly, thanks! How would I be able to modify this to include capital letters and have the user choose whether to include them, though? Or would I need to modify the code block?

Collectives™ on Stack Overflow

Generate random string in JavaScript (for a Discord bot)

2 Answers 2

2 Comments

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related