how to deal with “DEPRECATED use https://github.com/pillarjs/path-to-regexp” message

Question

I am quite sure it is really a dummy question for more experienced programmers but I can't figure out how to fix it. Well, the message clear says I am using some deprecated library so it is expected I upgrade it. As far as I can see, this message is related to routing functionality but I can't find how to change from "express.Router()" to some use of "require('path-to-regexp')". Am I confused on the purpose of such message? If not, how to fix the program below in order to not get such "deprecated" warning? As far as I understand, the code below is 100% compliance and updated with NOdeJs Express version 4.

PS.: I am using debian and if I type nodejs --version I get: v4.2.6

server.js:

 var router = express.Router();
var index = require('./routes/index').router;
app.use('/',index);

var server = app.listen(3000,function(){

});

index.js:

   var express = require('express');
   var router = express.Router();
   router.get('/',function(req,res){

        res.send("Welcome to Node JS");
    });
    router.get('/about',function(req,res){

        res.send("This is About page");
    });

    var api = router.route('/api/v1/user');
    api.all(function(req,res,next){

        console.log(req.method,req.url);
        next();
    });
    ...
        //this line is the Master
        module.exports.router = router;

Answer 1

The problem is with your express package. Updating the express module will do the trick.

npm update express --save