How to pass variable from app.js to routes/index.js?

Question

I'm using shrinkroute https://npmjs.org/package/shrinkroute to make links in nodejs. I get error 500 ReferenceError: shrinkr is not defined

How to pass shrinkroute to routes/index.js? Is there a better way to create url by passing query string args?

//app.js
var app = express();

var shrinkr = shrinkroute( app, {
    "user": {
        path: "/user/:id?",
        get: routes.showOrListUsers
    }
});
//url method works in app.js    
var url = shrinkr.url( "user", { id: 5, page:40, type:'a' } );
console.log(url);

app.use( shrinkr.middleware );

//routes/index.js
exports.showOrListUsers = function(req, res, next) {                       
    console.log(req.params); 
    //shrinkr errors out in index.js                                      
    var url2 = shrinkr.url( "users", {name: "foo"});                       
    console.log(url2);                                                                         
}      

Answer 1

One solution would be to store shrinkr in your app object using app.set:

// app.js
...
app.set('shrinkr', shrinkr);
...

In routes/index.js, you can access it through the req.app or res.app objects:

exports.showOrListUsers = function(req, res, next) {
  var shrinkr = req.app.get('shrinkr');
  ...
};

Answer 2

A bit late to the party, but the following works as well:

app.js

var my_var = 'your variable';

var route = require('./routes/index')(my_var);
app.get('/', route);

and meanwhile in route.js

var express = require('express')
,   router = express.Router()

// Router functions here, as normal; each of these
// run only on requests to the server

router.get('/', function (req, res, next) {
    res.status(200).end('Howdy');
});


module.exports = function(my_var){

    // do as you wish
    // this runs in background, not on each
    // request

    return router;
}