MQTT-parser

Split and parse MQTT packet from buffer.

MQTT protocol document: EN: http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html ZH: https://mcxiaoke.gitbooks.io/mqtt-cn/content/

Usage

/* javascript */
const mqttParser = require('mqtt-parser')
const connectBuffer = Buffer.from([
  16, 56, // Header
  0, 4, // Protocol ID length
  77, 81, 84, 84, // Protocol ID
  3, // Protocol version
  246, // Connect flags
  0, 30, // Keepalive
  0, 5, // Client ID length
  104, 101, 108, 108, 111, // Client ID
  0, 6, // Will topic length
  228, 189, 160, 229, 165, 189, // Will topic
  0, 8, // Will payload length
  112, 97, 121, 108, 111, 97, 100, 126, // Will payload
  0, 8, // Username length
  117, 115, 101, 114, 110, 97, 109, 101, // Username
  0, 9, // Password length
  112, 52, 36, 36, 119, 48, 194, 163, 100 // Password
])

let packets = mqttParser.parse(connectBuffer)
console.log(packets[0])
/*
  { packetType: 1,
    flags: 0,
    remainLength: 56,
    buffer: <Buffer 10 38 00 04 4d 51 54 54 03 f6 00 1e 00 05 68 65 6c 6c 6f 00 06 e4 bd a0 e5 a5 bd 00 08 70 61 79 6c 6f 61 64 7e 00 08 75 73 65 72 6e 616d 65 00 09 70 ... >,
    protocolName: 'MQTT',
    protocolLevel: 3,
    connectFlags: { 
      username: 1,
      password: 1,
      willRetain: 1,
      willQoS: 2,
      willFlag: 1,
      cleanSession: 1,
      reserved: 0 },
      keepAlive: 30,
      clientId: 'hello',
      willTopic: '你好',
      willMessage: 'payload~',
      username: 'username',
      password: 'p4$$w0£d'
    }
  }
*/

packets = mqttParser.parse(Buffer.concat([connectBuffer, connectBuffer, ...otherTypesPacket]))
console.log(packets)
/*
  [{ packetType: 1, ... },
  { packetType: 1, ... },
  ...]
*/

/* typescript */
import { parse, PacketType, Packet } from 'mqtt-parser'
const packets = mqttParser.parse(Buffer.from(connectBuffer)) // packets: BasePacket[]
if (packets[0].packetType === PacketType.CONNECT) {
  let packet = packet[0] as Packet.Connect
  packet.willTopic // code complete
}

API

parse(buffer: Buffer): BasePacket[]