how to include js file with no error? : i want to separate my route file in nodejs

i use restify framework and this is part of my code

    app.routes((app)=>{
      require(__dirname + '/../routes/web.js')
    })


routes/web.js

    app.get('/', function (req, res, next) {
        console.log("object");
    })

when run the program i get this error

>  app is not a defined

who can i fix that??

in web.js  "app" is undefined while i sended it to function

