Call app.js function in route file Node.js

Question

In app.js I have a function I want to call from a routes file.

This is simplified of course.

app.js

var express = require('express');
var app = express();

var foo = function() {
  return 'bar';
}

module.exports = app;

index.js

I tried to require('../app.js') and call app.foo but that didn't work.

Are you trying to call foo from outside app.js? What you have at the moment is a module that exports an instance of express... — James
– James, Commented Jul 16, 2015 at 15:44
@Tholle I open a sqlite database in app.js and want to have a function on the server that performs queries and returns the results on a route call. — NorCalKnockOut
– NorCalKnockOut, Commented Jul 16, 2015 at 15:46
@Tholle never thought of that. I'm new to all this. Ill give that a shot — NorCalKnockOut
– NorCalKnockOut, Commented Jul 16, 2015 at 15:49

James · Accepted Answer · 2015-07-16 16:13:15Z

3

If you want to export both app and foo then you could export an object surfacing both

module.exports = {
    app: app,
    foo: foo
}

Or alternatively, you could do

module.exports.app = app;
module.exports.foo = foo;

Then in your routes

var app = require('../app').app,
    foo = require('../app').foo;

answered Jul 16, 2015 at 15:49

James

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10 Comments

Thanks, now how would I call foo in the routes? foo( );?

@NorCalKnockOut yes, the module exports the function foo from the app.js file so you would just call it like any normal function.

I keep getting undefined is not a function for foo();

Do you actually have a function called foo in app.js?

Yeah, var foo = function() { return 'bar'; }

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