connect-mongo:Error: Connection strategy not found

app.use(session({
  secret: settings.cookieSecret,
  key: settings.db,//cookie name
  cookie: {maxAge: 1000 * 60 * 60 * 24 * 30},//30 days
  resave: false,
  saveUninitialized: true,
  store: new MongoStore({
    /*db: settings.db,
    host: settings.host,
    port: settings.port*/
    url: 'mongodb://localhost/blog'
  })}));

附：https://cnodejs.org/topic/567a1120222744630726b244

在此感谢！