Set up your Node.js and Express Development Environment

In this guide we’ll cover how to set up your Node.js development environment for an Express project. We’ll also walk through some helpful tools that we recommend for all Node.js applications that use Twilio: ngrok and the Twilio Node.js SDK

Install Node.js

How you install Node.js varies depending on your operating system.

Operating System Instructions
OS X The easiest way to install Node.js on OS X is to use the official installer from nodejs.org. You can also use Homebrew if you prefer.
Windows The easiest way to install Node.js on Windows is the official installer from nodejs.org. You can also use Chocolatey if you prefer.
Linux The exact instructions to install Node.js vary by distribution. Find instructions for yours here.

Install a Text Editor or IDE

Before we can start our Node.js project we’ll need a place to write our code.

If you already have a code writing tool of choice, you can stick with it for developing your Node.js application. If you're looking for something new, we recommend trying out a few options: 

  • Sublime Text is a text editor popular for its ease of use and extensibility. Start here if you’re eager to get coding and don’t think you’ll want a lot of frills in your development environment.
  • Visual Studio Code is an Integrated Development Environment (IDE) we like to use for JavaScript. It takes longer to set up but comes with more helpful tools already installed.
  • Node.js Tools for Visual Studio is a great option if you're already a Visual Studio user.
  • Vim is a perennial favorite text editor among advanced users.

If you’re new to programming, we recommend giving Sublime Text and Visual Studio Code each a try before you settle on your favorite. Many developers here at Twilio are using either - or both!

Start a New Node.js Project with "npm init"

Before starting any new Node.js project we should run npm init to create a new package.json file for our project.

Create a new empty directory in your development environment and run npm init. You'll then answer a few basic questions about your project, and npm will create a new package.json file for you when you're done.

01057-abaker:myproject abaker$ npm init
This utility will walk you through creating a package.json file.
It only covers the most common items, and tries to guess sensible defaults.

See `npm help json` for definitive documentation on these fields
and exactly what they do.

Use `npm install <pkg> --save` afterwards to install a package and
save it as a dependency in the package.json file.

Press ^C at any time to quit.
name: (myproject)
version: (1.0.0)
description: A sample Express + Twilio project
entry point: (index.js)
test command:
git repository: defunkt/myproject
keywords:
author: Jane Doe
license: (ISC)
About to write to /Users/jdoe/myproject/package.json:

{
  "name": "myproject",
  "version": "1.0.0",
  "description": "A sample Express + Twilio project",
  "main": "index.js",
  "dependencies": {},
  "devDependencies": {},
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "repository": {
    "type": "git",
    "url": "git+https://github.com/defunkt/myproject.git"
  },
  "author": "Jane Doe",
  "license": "ISC",
  "bugs": {
    "url": "https://github.com/defunkt/myproject/issues"
  },
  "homepage": "https://github.com/defunkt/myproject#readme"
}


Is this ok? (yes)

Now we're ready to install our Node.js dependencies.

Install Express.js and the Twilio Node.js SDK

We’re almost ready to start writing our Express web application, but first we need to install the Express package using npm.

# Use npm to install the express and twilio packages
$ npm install --save express twilio
myproject@1.0.0 /Users/abaker/myproject
├── express@4.14.0
└── twilio@3.0.0

Node.js uses npm to manage dependencies, so the command to pull Express and the Twilio SDK into our development environment is npm install --save express twilio.

The --save flag tells npm to add the Express and Twilio packages to the dependencies object in our project's package.json file. When we want to install these same packages again in the future - like on a production server - we can just run npm install.

Create a Simple Express.js Application

We can test that our development environment is configured correctly by creating a simple Express application. We’ll grab the ten-line example from Express's documentation and drop it in a new file called index.js.

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

app.get('/', function (req, res) {
  res.send('Hello World!');
});

app.listen(3000, function () {
  console.log('Example app listening on port 3000!');
});

We can then try running our new Express application with the command node index.js. If you open http://localhost:3000 in your browser and you should see the “Hello World!” response.

Note: If you’re using a virtual machine for your development environment, like vagrant, you might not be able to see your Express application at the localhost host name. Continue on to the ngrok section for an easy way to fix this.

Install ngrok for Local Development

Once you see your sample Express application’s “Hello World!” message, your development environment is ready to go. But for most Twilio projects you’ll want to install one more helpful tool: ngrok.

Most Twilio services use webhooks to communicate with your application. When Twilio receives an incoming phone call, for example, it reaches out to a URL in your application for instructions on how to handle the call.

When you’re working on your Express application in your development environment your app is only reachable by other programs on the same computer, so Twilio won’t be able to talk to it.

Ngrok is our favorite tool for solving this problem. Once started, it provides a unique URL on the ngrok.io domain which will forward incoming requests to your local development environment.

To start, head over to the ngrok download page and grab the binary for your operating system: https://ngrok.com/download

Once downloaded, make sure your Express application is running and then start ngrok using this command: "./ngrok http 3000". You should see output similar to this:

ngrok screen

Look at the “Forwarding” line to see your unique Ngrok domain name (ours is "aaf29606.ngrok.io") and then point your browser at that domain name.

If everything’s working correctly, you should see your Express application’s “Hello World!” message displayed at your new ngrok URL.

Anytime you’re working on your Twilio application and need a URL for a webhook you should use ngrok to get a publicly accessible URL like this one.

Andrew Baker
Paul Kamp
Kevin Whinnery
Agustin Camino
Jose Oliveros
David Prothero

Need some help?

We all do sometimes; code is hard. Get help now from our support team, or lean on the wisdom of the crowd browsing the Twilio tag on Stack Overflow.