Problem with node.js module.exports - I can't display data

JavaScript
1

INDEX.JS file:

var dummy = require('./routes/dummy.js');
var showdata = require('./routes/showdata.js');
var somemore = require('./routes/somemore.js');

var app = express();

app.use('/dummy', dummy);
app.use('/showdata', showdata);
app.use('/somemore', somemore);

DUMMY.JS file:

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

module.exports = function()
{
	var data = 'dummy.js';
	console.log('Im a programer! - look it will show up!);
	return router;
};

//or: module.exports = {data : 'dummy.js', router : router};

SHOWDATA.JS file:

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

var readData = require(./dummy.js);

router.get('/', function(req, res, next)
{
	res.render('showdata');
});

SHOWDATA.EJS

<!DOCTYPE html>
<html>
<head>
<title>test</title>
</head>
<body>
<h1>showdata.ejs</h1>
<%= data %>
</body>
</html>

OK, now when I type console.log(readData().data); in showdata.js file I can’t access var data = ‘dummy.js’; (undefined). Cause it’s local variable and not a property… right ( console.log() is working fine )? But is there any way to get to it - display it in showdata.js file? Even when I use module.exports as object - module.exports = {data : ‘dummy.js’, router : router}; I get “Router.use() requires middleware function but got a Object”… Thanks for pointing any directions.

2

no. if the variable is not in scope then there is no way to access it. that is the whole point of scope otherwise nothing would work.

3

@Dormilich thanks you for your input!

BUT everything I want to export is in module.exports so explain it to me how it disturb the scope? As I understand module.exports object works like ability to export everything ->inside it<-. Console.log is working fine and I can display it wherever I want. When I change var precious_data to precious_data it should be available everywhere as a global data but it’s not in this particular case.

When I use object in module.exports:

var func = function() {console.log('Im a programer from function!');}
var read = 'text to read';

module.exports = {data : 'dummy.js', func : func, read: read, router : router};

everything is working fine (even when some of those are not global vars)…

var readData = require(./dummy.js).data; // or require(./dummy.js).func - whatever;
console.log(readData); // all good

well I needed to disable app.use(‘/dummy’, dummy); cause of Router.use() requires middleware function but got a Object… why it must be a function… why it conflict with module.exports = router;… few lines on this subject won’t hurt my brain either :slight_smile:

Can you elaborate more on this topic? Help me understand this basic concept.

4

neither of them are global variables. that is the trick with module.exports, it keeps its scope to itself and ony publishes the desired stuff. Like in the (revealing) module pattern.

5

ok, got it.

So how to move data from one module to the other by module.exports? I need to define all data as global - that the only way?

6

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