fix: buffer is not defined in browser (#1420)

Author: flyfishzy

lib/connect/ali.js

@@ -1,5 +1,6 @@
 'use strict'
 
+const { Buffer } = require('buffer')
 const Transform = require('readable-stream').Transform
 const duplexify = require('duplexify')
 

lib/connect/ws.js

@@ -1,5 +1,6 @@
 'use strict'
 
+const { Buffer } = require('buffer')
 const WS = require('ws')
 const debug = require('debug')('mqttjs:ws')
 const duplexify = require('duplexify')

lib/connect/wx.js

@@ -1,5 +1,6 @@
 'use strict'
 
+const { Buffer } = require('buffer')
 const Transform = require('readable-stream').Transform
 const duplexify = require('duplexify')
 

types/lib/connect/index.d.ts

@@ -1,25 +1,19 @@
-import { IClientOptions, MqttClient } from "../client";
-/**
- * connect - connect to an MQTT broker.
- *
- * @param {String} brokerUrl - url of the broker
- */
-declare function connect(brokerUrl: string): MqttClient;
+import { IClientOptions, MqttClient } from '../client'
 
 /**
  * connect - connect to an MQTT broker.
  *
  * @param {Object} opts - see MqttClient#constructor
  */
-declare function connect(opts: IClientOptions): MqttClient;
+declare function connect (opts: IClientOptions): MqttClient
 
 /**
  * connect - connect to an MQTT broker.
  *
  * @param {String} brokerUrl - url of the broker
  * @param {Object} opts - see MqttClient#constructor
  */
-declare function connect(brokerUrl: string, opts: IClientOptions): MqttClient;
+declare function connect (brokerUrl: string, opts?: IClientOptions): MqttClient
 
-export { connect };
-export { MqttClient };
+export { connect }
+export { MqttClient }