I'm still new to Express, so please bear with me.

What I'm trying to do is store some of my environmental variables in a global variable such that they can be accessed in any route without having to redeclare the variables within each route.

Note that I used the Express Generator to set up the project scaffolding.

Here's a stripped-down example of what I'm trying to do:

App.js

const express = require('express');

// Load Routes
const inventoryRouter = require('./src/routes/inventory');

// Instantiate Express/Assign App Var
const app = express();

// Set Global Env Vars
app.set('DevUrl', process.env.Dev_URL || null);

// Use Routes
app.use('/inventory', inventoryRouter);

module.exports = app;

Inventory.js

const express = require('express');
const router = express.Router();

// Require Inventory Controller
const inventoryController = require('../controllers/inventoryController');

// Inventory Routes
router.get('/', inventoryController.get_inventory);
router.post('/', inventoryController.update_inventory);

module.exports = router;

InventoryController.js

const router = express.Router();

// Store Vars
const LocalRouteVariable = app.get('DevUrl') + 'Some String';

// Rest of Controller Code ...

Question "app" is not defined in the controller. So, my question is, how can I get the value of "DevUrl"?