can't connect to offline server with resource pack

[nycki93]

• [x] The FAQ doesn't contain a resolution to my issue

Versions

• mineflayer: 4.20.1
• server: paper 1.20.4
• node: 20.0.0

Detailed description of a problem

I am trying to make a bot to AFK for me on an offline server with a login plugin. The server has a custom resource pack. When I connect, the bot first has to deny the resource pack, and then it crashes here:

TypeError: Serialization error for configuration.toServer : Write error for undefined : Cannot read properties of undefined (reading '0')
    at Function.parse (***\node_modules\uuid-1345\index.js:137:36)
    at module.exports.Write.UUID (***\node_modules\minecraft-protocol\src\datatypes\compiler-minecraft.js:48:76)

What did you try yet?

I edited compiler-minecraft and changed this:

UUID: ['native', (value, buffer, offset) => {
  const buf = value.length === 32 ? Buffer.from(value, 'hex') : UUID.parse(value)
  buf.copy(buffer, offset)
  return offset + 16
}],

into this:

UUID: ['native', (value, buffer, offset) => {
  if (value) {
    const buf = value.length === 32 ? Buffer.from(value, 'hex') : UUID.parse(value)
    buf.copy(buffer, offset)
  }
  return offset + 16
}],

And it resolved my issue. Additionally, I was able to reproduce the bug on a localhost server using no other plugins or configs other than setting a server resource pack.

Your current code

import { readFileSync } from 'node:fs';
import { createBot } from 'mineflayer';

const config = JSON.parse(readFileSync('config.json'));
const { host, port, password } = config;

const bot = createBot({
    host,
    port,
    username: 'nycki_afk',
    auth: 'offline',
});

bot.on('spawn', () => {
    bot.chat(`/login ${password}`)
});

bot.on('resourcePack', (url) => {
    bot.denyResourcePack();
});

bot.on('error', console.log)

bot.on('kicked', console.log)