rsup-mqtt

Elegant wrapper for the paho mqtt client

Usage no npm install needed!

<script type="module">
  import rsupMqtt from 'https://cdn.skypack.dev/rsup-mqtt';
</script>

README

Rsup MQTT

📢 Elegant wrapper for the paho mqtt client

npm downloads

Why

pee

Paho is fast and light, but interface is not good. So I wrapped to better interface...

Install

yarn add rsup-mqtt

//es6
import {connect} from "rsup-mqtt";

//commonjs
var connect = require('rsup-mqtt').connect;

browser

<script src="https://unpkg.com/rsup-mqtt"></script>
<script>
 var connect = RsupMQTT.connect;
</script>

Example

Basic

const client = await connect('ws://mqtt.test.io')

client.subscribe('topic').on(message => console.log(message.string))
client.publish('topic', 'hello mqtt')

// => hello mqtt

API

connect(options)

Connects to the broker. Returns Promise<Client>.

connect({host: 'mqtt.test.io', ssl: true, path: '/mqtt'})
  .then(client => { ... })

// or
connect('wss://mqtt.test.io/mqtt')
  .then(client => { ... })

Options

  • host - Host address, required.

  • port - Defaults is 443 or 80.

  • path - Defaults is '/'.

  • ssl - Defaults is false.

  • clientId Defaults is random string.

  • hosts - Optional. fallback urls.

  • keepalive Defaults is 60.

  • username Optional.

  • password Optional.

  • cleanSession Defaults is false.

  • reconnect Defaults is true.

  • mqttVersion Defaults is 4.

  • mqttVersionExplicit Default value is true if the "mqttVersion" is 4, and false otherwise.

  • will Optional.

    • topic Required.
    • payload Required.
    • qos Defaults is 0
    • retain Defaults is false.

  • Constructor - See Constructor

Constructor

If want to extend Client.

import {Client, connect} from 'rsup-mqtt'

class CustomClient extends Client{ ... }

connect({ Constructor: CustomClient, ...opts })

Client

client.isConnected()

Returns whether the client is connected.

client.on(eventName, listener)

Add an event listener.

Events
  • message - When a message is received.
  • sent - When a message is sent.
  • close - When a connection is completely closed.
  • error - When an error occurs.
  • reconnect - When start reconnecting.
Message type event - message | sent

Receive topic and message. See details about Message.

client.on('sent', (topic, message) => console.log(topic, message.string))

client.publish('topic', 'hello~')
// => "topic", "hello~"
Error type event - close | error | reconnect

Receive error or not. See details about Error.

client.on('close', err => {
  if(err.occurred()) alert('disconnected due to an connection error : ' + err.message)
})

client.once(eventName, listener)

Add an event listener. Runs once.

client.off(eventName [, listener])

Remove the event listener(s).

client.off('message', listener)
client.off('message') // If no listener, remove all,

client.onMessage(topic, listener)

Add an listener for received message.

client.onMessage('topic', message => console.log(message.string))

client.onSent(topic, listener)

Add an listener for sent message.

client.removeMessageListener(topic [, listener])

Remove the listener(s) for received message.

client.removeSentListener(topic [, listener])

Remove the listener(s) for sent message.

client.subscribe(topic)

Subscribe to a topic. Returns subscription instance. See details about Subscription.

client.unsubscribe(topic [, removeListeners])

Unsubscribe from a topic. If removeListeners is true, remove all the topic listeners.

client.subscribed()

Returns an array of subscribed topic.

client.subscribe('topic1')
client.subscribe('topic2')

console.log(client.subscribed())
// => ['topic1', 'topic2']

client.publish(topic, payload [, options])

Publish a message to a topic.

client.publish('topic', 'hello') // string message
client.publish('topic', {text: 'hello~'}) // Convert object to json string.
client.publish('topic', (new TextEncoder()).encode('hello')) // buffer message
options
  • qos Defaults is 0.
  • retain Defaults is false.

client.send(topic, payload [, options])

Alias client.publish().

client.disconnect()

Disconnect the connection.

client.reconnect()

Connect again using the same options. Returns Promise<void>.

Subscription

subscription.topic

Subscribed topic.

const subscription = client.subscribe('topic')

console.log(subscription.topic)
// => topic

subscription.on(listener)

Add an listener for received topic message.

subscription.off([listener])

Remove the topic listener(s).

subscription.publish(payload [, options])

Publish a message to topic.

subscription.send(payload [, options])

Alias subscription.publish().

subscription.unsubscribe([removeListeners])

Unsubscribe from a topic. If removeListeners is true, remove all the topic listeners.

Message

message.topic

Message's topic.

message.string

A payload of string type.

message.json

A payload of json type.

message.bytes

A payload of buffer type.

message.qos

Message's qos. Returns number.

message.retain

Message's retain. Returns boolean.

message.dup

Duplicate Message or not. Returns boolean.

Error

error.code

Error's code number.

error.message

Error's message

error.occurred()

Error occurred or not. Returns boolean.

error.is(code)

Compare error code number. Returns boolean.

import {ERROR} from 'rsup-mqtt'

console.log(error.is(ERROR.BUFFER_FULL))
// => true or false
Error Codes
  • OK - No error.
  • CONNECT_TIMEOUT - Connect timed out.
  • SUBSCRIBE_TIMEOUT - Subscribe timed out.
  • UNSUBSCRIBE_TIMEOUT - Unsubscribe timed out.
  • PING_TIMEOUT - Ping timed out.
  • INTERNAL_ERROR - Internal error.
  • CONNACK_RETURNCODE - Bad Connack return code.
  • SOCKET_ERROR - Socket error.
  • SOCKET_CLOSE -Socket closed.
  • MALFORMED_UTF -Malformed UTF data.
  • UNSUPPORTED - Not supported by this browser.
  • INVALID_STATE - Invalid state.
  • INVALID_TYPE - Invalid type.
  • INVALID_ARGUMENT -Invalid argument.
  • UNSUPPORTED_OPERATION - Unsupported operation.
  • INVALID_STORED_DATA - Invalid data in local storage.
  • INVALID_MQTT_MESSAGE_TYPE - Invalid MQTT message type.
  • MALFORMED_UNICODE - Malformed Unicode string.
  • BUFFER_FULL - Message buffer is full.

License

MIT