# Check your Ruby version $ ruby --version ruby 2.3.1p112 (2016-04-26 revision 54768)
If Ruby is already installed on your system, you can check its version by running
How you install Ruby varies depending on your operating system.
|OS X||The easiest way to install Ruby on OS X is to use the official installer from ruby-lang.org. You can also use Homebrew if you prefer.|
|Windows||The easiest way to install Ruby on Windows is the official installer from RubyInstaller. You can also use Chocolatey if you prefer.|
|Linux||The exact instructions to install Ruby vary by distribution. Find instructions for yours here.|
Ruby Version Manager or RVM, is a unix-like software platform designed to manage multiple installations of Ruby on the same device.
$ gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 $ curl -sSL https://get.rvm.io | bash -s stable --ruby
Before we can start our Ruby project we’ll need something to write it with.
If you already have a code writing tool of choice, you can stick with it for developing your Ruby 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.
- RubyMine is a full Integrated Development Environment (IDE) for Ruby. It takes longer to set up but comes with more helpful tools already installed.
- Vim is a perernnial favorite text editor among advanced users
If you’re new to programming, we recommend giving Atom and Sublime Text each a try before you settle on your favorite.
We’re almost ready to start writing our Sinatra web application, but first we need to install the Sinatra library.
First, you need a Gemfile with the following content on it.
# Gemfile source 'https://rubygems.org' gem 'sinatra' gem 'twilio-ruby'
Ruby projects uses Bundler to manage dependencies, so the command to pull Sinatra and the Twilio SDK into our development environment is
$ bundle install Using builder 3.2.2 Using jwt 1.5.6 Using multi_json 1.12.1 Using rack 1.6.5 Using tilt 2.0.5 Using bundler 1.13.3 Using twilio-ruby 4.13.0 Using rack-protection 1.5.3 Using sinatra 1.4.7 Bundle complete! 2 Gemfile dependencies, 9 gems now installed. Use `bundle show [gemname]` to see where a bundled gem is installed.
We can test that our development environment is configured correctly by creating a simple Sinatra application. We’ll grab the example from Sinatra's documentation and drop it in a new file called `index.rb`.
# index.rb require 'sinatra' require 'twilio-ruby' get '/' do content_type 'text/xml' Twilio::TwiML::VoiceResponse.new do | response | response.say(message: 'Hello World') end.to_s end
We can then try running our new Sinatra application with the command
ruby index.rb -p 3000. You can then open http://localhost:3000 in your browser and you should see the
<?xml version="1.0" encoding="UTF-8"?><Response><Say>Hello World</Say></Response> response.
Once you see your sample Sinatra application’s “<?xml version="1.0" encoding="UTF-8"?><Response><Say>Hello World</Say></Response>” 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 Sinatra 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 Sinatra application is running and then start ngrok using this command: "./ngrok http 3000". You should see output similar to this:
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 Sinatra application’s “<?xml version="1.0" encoding="UTF-8"?><Response><Say>Hello World</Say></Response>” 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.