node-gamedig/protocols/minecraftbedrock.js

import Core from './core.js'

export default class minecraftbedrock extends Core {
  constructor () {
    super()
    this.byteorder = 'be'
  }

  async run (state) {
    const bufs = [
      Buffer.from([0x01]), // Message ID, ID_UNCONNECTED_PING
      Buffer.from('1122334455667788', 'hex'), // Nonce / timestamp
      Buffer.from('00ffff00fefefefefdfdfdfd12345678', 'hex'), // Magic
      Buffer.from('0000000000000000', 'hex') // Cliend GUID
    ]

    return await this.udpSend(Buffer.concat(bufs), buffer => {
      const reader = this.reader(buffer)

      const messageId = reader.uint(1)
      if (messageId !== 0x1c) {
        this.logger.debug('Skipping packet, invalid message id')
        return
      }

      const nonce = reader.part(8).toString('hex') // should match the nonce we sent
      this.logger.debug('Nonce: ' + nonce)
      if (nonce !== '1122334455667788') {
        this.logger.debug('Skipping packet, invalid nonce')
        return
      }

      // These 8 bytes are identical to the serverId string we receive in decimal below
      reader.skip(8)

      const magic = reader.part(16).toString('hex')
      this.logger.debug('Magic value: ' + magic)
      if (magic !== '00ffff00fefefefefdfdfdfd12345678') {
        this.logger.debug('Skipping packet, invalid magic')
        return
      }

      const statusLen = reader.uint(2)
      if (reader.remaining() !== statusLen) {
        throw new Error('Invalid status length: ' + reader.remaining() + ' vs ' + statusLen)
      }

      const statusStr = reader.rest().toString('utf8')
      this.logger.debug('Raw status str: ' + statusStr)

      const split = statusStr.split(';')
      if (split.length < 6) {
        throw new Error('Missing enough chunks in status str')
      }

      state.raw.edition = split.shift()
      state.name = split.shift()
      state.raw.protocolVersion = split.shift()
      state.raw.mcVersion = split.shift()
      state.version = state.raw.mcVersion
      state.numplayers = parseInt(split.shift())
      state.maxplayers = parseInt(split.shift())
      if (split.length) state.raw.serverId = split.shift()
      if (split.length) state.map = split.shift()
      if (split.length) state.raw.gameMode = split.shift()
      if (split.length) state.raw.nintendoOnly = !!parseInt(split.shift())
      if (split.length) state.raw.ipv4Port = split.shift()
      if (split.length) state.raw.ipv6Port = split.shift()

      return true
    })
  }
}