message: [fix] Back compatibility mqtt host url
diff: @@ -52,7 +52,7 @@ function init (config) {
  clean: config.clean,
  rejectUnauthorized: !config.allowSelfsigned,
  protocol: protocol,
  - host: parsed.hostname,
  + host: parsed.hostname || config.host,
  port: config.port,
  will: {
  topic: this.getClientTopic(),
  