node.js - 无法在NodeJS应用程序的Heroku上添加npm模块

我在Heroku上托管一个NodeJS应用程序，它重命名了sFTP服务器上的文件。请在下面找到我的app.js代码。如果我删除ssh2-sftp-client npm模块，一切工作正常。但是我无法建立sFTP连接。我对Heroku和NodeJS都很陌生。你能帮我这个忙吗？在本地上一切正常。我对如何将npm ssh2-sftp-client添加到Heroku以便正确执行nodeJS代码感到困惑。

    let Client = require('ssh2-sftp-client');
let sftp = new Client();
sftp.connect({
  host: 'host',
  port: 'port',
  username: 'user',
  password: 'password'
}).then(() => {
     return sftp.rename('/After30/Sunil.txt','/After30/Sunil.csv')

}).then(() => {
  console.log('Closing SFTP');
   return sftp.end();

}).catch(err => {
  console.log(err, 'catch error');
});

请找到package.json文件代码，

    {
  "name": "jb-activity-template",
  "version": "1.0.0",
  "description": "Journey Builder Activity Template",
  "engines": {
    "node": "6.11.1"
  },
  "scripts": {
    "start": "node app.js"
  },
  "repository": {
    "type": "git",
    "url": "git+https://github.com/bhanuatsfdc/SFMC/journey-builder-activity-template.git"
  },
  "keywords": [
    "journey",
    "builder",
    "salesforce marketing cloud",
    "heroku"
  ],
  "author": "Devs United",
  "license": "ISC",
  "bugs": {
    "url": "https://github.com/bhanuatsfdc/SFMC/journey-builder-activity-template/issues"
  },
  "homepage": "https://github.com/bhanuatsfdc/SFMC/journey-builder-activity-template#readme",
  "dependencies": {
    "body-parser": "^1.18.2",
    "bower": "^1.8.0",
    "errorhandler": "^1.5.0",
    "express": "^4.15.4",
    "jsonwebtoken": "^8.0.1",
    "ssh2-sftp-client": "^5.0.1",
    "request": "^2.81.0",
    "require": "^2.4.20"
  }
}

请找到我的应用日志记录，