express-session deprecated undefined resave option



app.use(session({

    //处理错误express-session deprecated undefined resave option; provide resave option app.js
    resave: false,//添加这行
    saveUninitialized: true,//添加这行

    secret: settings.cookieSecret,
    key: settings.db,//cookie name
    cookie: {maxAge: 1000 * 60 * 60 * 24 * 30},//30 days
    store: new MongoStore({
        url: 'mongodb://' + settings.host + '/' + settings.db
        //db: settings.db,
        //host: settings.host,
        //port: settings.port
    })
}));