[Node.js] CommonJS Modules

CoomonJS modules provide a clean syntax for importing dependencies. This lesson will take a look at the basics of using CommonJS modules.

app.js

var dep = require('./dep');

console.log(dep); // Exports a string back

dep.js

module.exports =  "Exports a string back";

You can exports anything, such as a function:

app.js

var dep = require('./dep');

console.log(dep()); // Export a function back

dep.js

module.exports = function() {
    return "Exports a function back";
}

Exprots multi-value:

app.js

var dep = require('./dep');

console.log(dep.foo, dep.bar); //foo, bar

dep.js

module.exports = {
    foo: "foo",
    bar: "bar"
}

Normally, you should do like this, using exprots object directly:

dep.js

exports.foo = "foo";
exports.bar = "bar";