IVR: Phone Tree with Ruby and Rails

Learn to create an interactive voice response (IVR) system with Twilio Programmable Voice and your Ruby web application by using the <Gather>, <Say>, and <Dial> TwiML elements to handle phone tree logic inside an application. You can use this guide to send notifications, create self-service automation, build inbound call centers, build outbound call centers, or implement AI or ML transcription.

See Related reference documentation to learn more about the TwiML voice elements used in this guide.

This Ruby on Rails sample application is modeled after a typical call center experience with an IVR.

Stranded aliens can call a phone number and receive instructions on how to get out of earth safely or call their home planet directly. In this tutorial we'll show you the key bits of code to make this work.

To run this sample app yourself, download the code and follow the instructions on GitHub.

Read how Livestream and other companies built IVR phone trees with Twilio. Find examples and sample code for many web languages on our IVR application page.

Answering a Phone Call

To initiate the phone tree, we need to configure one of our Twilio numbers to send our web application an HTTP request when we get an incoming call.

Click on one of your numbers and configure the Voice URL to point to our app. In our code the route will be /ivr/welcome.

Twilio console showing IVR webhook configuration for phone number with HTTP POST method.

If you don't already have a server configured to use as your webhook, ngrok is a great tool for testing webhooks locally.

With our Twilio number configured, we are prepared to respond to the Twilio request.

Respond to the Twilio request with TwiML

Our Twilio number is now configured to send HTTP requests to this controller method on any incoming voice calls. Our app responds with TwiML to tell Twilio what to do in response to the message.

In this case we tell Twilio to Gather the input from the caller and Say a welcome message.

Respond with TwiML to gather an option from the caller

app/controllers/twilio_controller.rb

1require 'twilio-ruby'
2
3
4class TwilioController < ApplicationController
5
6  def index
7    render plain: "Dial Me."
8  end
9
10  # POST ivr/welcome
11  def ivr_welcome
12    response = Twilio::TwiML::VoiceResponse.new
13    response.gather(num_digits: '1', action: menu_path) do |gather|
14      gather.say(message: "Thanks for calling the E T Phone Home Service. Please press 1 for
15      directions. Press 2 for a list of planets to call.", loop: 3)
16    end
17    render xml: response.to_s
18  end
19
20  # GET ivr/selection
21  def menu_selection
22    user_selection = params[:Digits]
23
24    case user_selection
25    when "1"
26      @output = "To get to your extraction point, get on your bike and go down
27        the street. Then Left down an alley. Avoid the police cars. Turn left
28        into an unfinished housing development. Fly over the roadblock. Go
29        passed the moon. Soon after you will see your mother ship."
30      twiml_say(@output, true)
31    when "2"
32      list_planets
33    else
34      @output = "Returning to the main menu."
35      twiml_say(@output)
36    end
37
38  end
39
40  # POST/GET ivr/planets
41  # planets_path
42  def planet_selection
43    user_selection = params[:Digits]
44
45    case user_selection
46    when "2"
47      twiml_dial("+19295566487")
48    when "3"
49      twiml_dial("+17262043675")
50    when "4"
51      twiml_dial("+16513582243")
52    else
53      @output = "Returning to the main menu."
54      twiml_say(@output)
55    end
56  end
57
58  private
59
60  def list_planets
61    message = "To call the planet Broh doe As O G, press 2. To call the planet
62    DuhGo bah, press 3. To call an oober asteroid to your location, press 4. To
63    go back to the main menu, press the star key."
64
65    response = Twilio::TwiML::VoiceResponse.new
66    response.gather(num_digits: '1', action: planets_path) do |gather|
67      gather.say(message: message, voice: 'Polly.Amy', language: 'en-GB', loop: 3)
68    end
69
70    render xml: response.to_s
71  end
72
73  def twiml_say(phrase, exit = false)
74    # Respond with some TwiML and say something.
75    # Should we hangup or go back to the main menu?
76    response = Twilio::TwiML::VoiceResponse.new
77    response.say(message: phrase, voice: 'Polly.Amy', language: 'en-GB')
78    if exit
79      response.say(message: "Thank you for calling the ET Phone Home Service - the
80      adventurous alien's first choice in intergalactic travel.")
81      response.hangup
82    else
83      response.redirect(welcome_path)
84    end
85
86    render xml: response.to_s
87  end
88
89  def twiml_dial(phone_number)
90    response = Twilio::TwiML::VoiceResponse.new do |r|
91      r.dial(number: phone_number)
92    end
93
94    render xml: response.to_s
95  end
96end

After reading the text to the caller and retrieving their input, Twilio will send this input to our application.

Where to send the caller's input

The gather's action parameter takes an absolute or relative URL as a value. In our case, this is the menu route.

When the caller has finished entering digits, Twilio will make a GET or POST request to this URL including a Digits parameter with the number our caller chose.

After making this request, Twilio will continue the current call using the TwiML received in your response. Any TwiML verbs occurring after a <Gather> are unreachable, unless the caller doesn't enter any digits.

Send caller input to the intended route

app/controllers/twilio_controller.rb

1require 'twilio-ruby'
2
3
4class TwilioController < ApplicationController
5
6  def index
7    render plain: "Dial Me."
8  end
9
10  # POST ivr/welcome
11  def ivr_welcome
12    response = Twilio::TwiML::VoiceResponse.new
13    response.gather(num_digits: '1', action: menu_path) do |gather|
14      gather.say(message: "Thanks for calling the E T Phone Home Service. Please press 1 for
15      directions. Press 2 for a list of planets to call.", loop: 3)
16    end
17    render xml: response.to_s
18  end
19
20  # GET ivr/selection
21  def menu_selection
22    user_selection = params[:Digits]
23
24    case user_selection
25    when "1"
26      @output = "To get to your extraction point, get on your bike and go down
27        the street. Then Left down an alley. Avoid the police cars. Turn left
28        into an unfinished housing development. Fly over the roadblock. Go
29        passed the moon. Soon after you will see your mother ship."
30      twiml_say(@output, true)
31    when "2"
32      list_planets
33    else
34      @output = "Returning to the main menu."
35      twiml_say(@output)
36    end
37
38  end
39
40  # POST/GET ivr/planets
41  # planets_path
42  def planet_selection
43    user_selection = params[:Digits]
44
45    case user_selection
46    when "2"
47      twiml_dial("+19295566487")
48    when "3"
49      twiml_dial("+17262043675")
50    when "4"
51      twiml_dial("+16513582243")
52    else
53      @output = "Returning to the main menu."
54      twiml_say(@output)
55    end
56  end
57
58  private
59
60  def list_planets
61    message = "To call the planet Broh doe As O G, press 2. To call the planet
62    DuhGo bah, press 3. To call an oober asteroid to your location, press 4. To
63    go back to the main menu, press the star key."
64
65    response = Twilio::TwiML::VoiceResponse.new
66    response.gather(num_digits: '1', action: planets_path) do |gather|
67      gather.say(message: message, voice: 'Polly.Amy', language: 'en-GB', loop: 3)
68    end
69
70    render xml: response.to_s
71  end
72
73  def twiml_say(phrase, exit = false)
74    # Respond with some TwiML and say something.
75    # Should we hangup or go back to the main menu?
76    response = Twilio::TwiML::VoiceResponse.new
77    response.say(message: phrase, voice: 'Polly.Amy', language: 'en-GB')
78    if exit
79      response.say(message: "Thank you for calling the ET Phone Home Service - the
80      adventurous alien's first choice in intergalactic travel.")
81      response.hangup
82    else
83      response.redirect(welcome_path)
84    end
85
86    render xml: response.to_s
87  end
88
89  def twiml_dial(phone_number)
90    response = Twilio::TwiML::VoiceResponse.new do |r|
91      r.dial(number: phone_number)
92    end
93
94    render xml: response.to_s
95  end
96end

Now that we have told Twilio where to send the caller's input, we can look at how to process that input.

app/controllers/twilio_controller.rb

1require 'twilio-ruby'
2
3
4class TwilioController < ApplicationController
5
6  def index
7    render plain: "Dial Me."
8  end
9
10  # POST ivr/welcome
11  def ivr_welcome
12    response = Twilio::TwiML::VoiceResponse.new
13    response.gather(num_digits: '1', action: menu_path) do |gather|
14      gather.say(message: "Thanks for calling the E T Phone Home Service. Please press 1 for
15      directions. Press 2 for a list of planets to call.", loop: 3)
16    end
17    render xml: response.to_s
18  end
19
20  # GET ivr/selection
21  def menu_selection
22    user_selection = params[:Digits]
23
24    case user_selection
25    when "1"
26      @output = "To get to your extraction point, get on your bike and go down
27        the street. Then Left down an alley. Avoid the police cars. Turn left
28        into an unfinished housing development. Fly over the roadblock. Go
29        passed the moon. Soon after you will see your mother ship."
30      twiml_say(@output, true)
31    when "2"
32      list_planets
33    else
34      @output = "Returning to the main menu."
35      twiml_say(@output)
36    end
37
38  end
39
40  # POST/GET ivr/planets
41  # planets_path
42  def planet_selection
43    user_selection = params[:Digits]
44
45    case user_selection
46    when "2"
47      twiml_dial("+19295566487")
48    when "3"
49      twiml_dial("+17262043675")
50    when "4"
51      twiml_dial("+16513582243")
52    else
53      @output = "Returning to the main menu."
54      twiml_say(@output)
55    end
56  end
57
58  private
59
60  def list_planets
61    message = "To call the planet Broh doe As O G, press 2. To call the planet
62    DuhGo bah, press 3. To call an oober asteroid to your location, press 4. To
63    go back to the main menu, press the star key."
64
65    response = Twilio::TwiML::VoiceResponse.new
66    response.gather(num_digits: '1', action: planets_path) do |gather|
67      gather.say(message: message, voice: 'Polly.Amy', language: 'en-GB', loop: 3)
68    end
69
70    render xml: response.to_s
71  end
72
73  def twiml_say(phrase, exit = false)
74    # Respond with some TwiML and say something.
75    # Should we hangup or go back to the main menu?
76    response = Twilio::TwiML::VoiceResponse.new
77    response.say(message: phrase, voice: 'Polly.Amy', language: 'en-GB')
78    if exit
79      response.say(message: "Thank you for calling the ET Phone Home Service - the
80      adventurous alien's first choice in intergalactic travel.")
81      response.hangup
82    else
83      response.redirect(welcome_path)
84    end
85
86    render xml: response.to_s
87  end
88
89  def twiml_dial(phone_number)
90    response = Twilio::TwiML::VoiceResponse.new do |r|
91      r.dial(number: phone_number)
92    end
93
94    render xml: response.to_s
95  end
96end

That was only the main menu and the first option. If the caller chooses '2', we will take them to the Planet Directory in order to collect more input.

The Planet Directory: Collect more input from the caller

If our callers choose to call their home planet, we will read them the planet directory. This is similar to a typical "company directory" feature of most IVRs.

In our TwiML response we use a Gather verb again to receive our caller's input. This time, the action verb points to the planets route, which will switch our response based on what the caller chooses.

The TwiML response we return for that route uses a Dial verb with the appropriate phone number to connect our caller to their home planet.The current numbers are hardcoded, but we can also set those numbers using environment variables.

Route users to a new phone number via the Planet Directory

app/controllers/twilio_controller.rb

1require 'twilio-ruby'
2
3
4class TwilioController < ApplicationController
5
6  def index
7    render plain: "Dial Me."
8  end
9
10  # POST ivr/welcome
11  def ivr_welcome
12    response = Twilio::TwiML::VoiceResponse.new
13    response.gather(num_digits: '1', action: menu_path) do |gather|
14      gather.say(message: "Thanks for calling the E T Phone Home Service. Please press 1 for
15      directions. Press 2 for a list of planets to call.", loop: 3)
16    end
17    render xml: response.to_s
18  end
19
20  # GET ivr/selection
21  def menu_selection
22    user_selection = params[:Digits]
23
24    case user_selection
25    when "1"
26      @output = "To get to your extraction point, get on your bike and go down
27        the street. Then Left down an alley. Avoid the police cars. Turn left
28        into an unfinished housing development. Fly over the roadblock. Go
29        passed the moon. Soon after you will see your mother ship."
30      twiml_say(@output, true)
31    when "2"
32      list_planets
33    else
34      @output = "Returning to the main menu."
35      twiml_say(@output)
36    end
37
38  end
39
40  # POST/GET ivr/planets
41  # planets_path
42  def planet_selection
43    user_selection = params[:Digits]
44
45    case user_selection
46    when "2"
47      twiml_dial("+19295566487")
48    when "3"
49      twiml_dial("+17262043675")
50    when "4"
51      twiml_dial("+16513582243")
52    else
53      @output = "Returning to the main menu."
54      twiml_say(@output)
55    end
56  end
57
58  private
59
60  def list_planets
61    message = "To call the planet Broh doe As O G, press 2. To call the planet
62    DuhGo bah, press 3. To call an oober asteroid to your location, press 4. To
63    go back to the main menu, press the star key."
64
65    response = Twilio::TwiML::VoiceResponse.new
66    response.gather(num_digits: '1', action: planets_path) do |gather|
67      gather.say(message: message, voice: 'Polly.Amy', language: 'en-GB', loop: 3)
68    end
69
70    render xml: response.to_s
71  end
72
73  def twiml_say(phrase, exit = false)
74    # Respond with some TwiML and say something.
75    # Should we hangup or go back to the main menu?
76    response = Twilio::TwiML::VoiceResponse.new
77    response.say(message: phrase, voice: 'Polly.Amy', language: 'en-GB')
78    if exit
79      response.say(message: "Thank you for calling the ET Phone Home Service - the
80      adventurous alien's first choice in intergalactic travel.")
81      response.hangup
82    else
83      response.redirect(welcome_path)
84    end
85
86    render xml: response.to_s
87  end
88
89  def twiml_dial(phone_number)
90    response = Twilio::TwiML::VoiceResponse.new do |r|
91      r.dial(number: phone_number)
92    end
93
94    render xml: response.to_s
95  end
96end

Use cases for IVR phone trees with Twilio Programmable Voice

See use cases for IVRs with Twilio Programmable Voice to learn about the different applications you can build with IVR phone trees.

Result

After following this guide, you can successfully process incoming voice calls and present an interactive menu using Twilio Programmable Voice in your application. You will have a live IVR system capable of listening to dual-tone multi-frequency (DTMF) keypad inputs, executing logic conditionally based on user choice, and dynamically forwarding or terminating calls based on your response payload.

Next steps

Explore the following guides to build on what you've learned in this guide:

Respond to incoming phone calls: Learn how to handle incoming webhooks from Twilio to dynamically direct callers.
Collect payments during calls: Use the <Pay> TwiML verb to securely collect payment information from callers.
Make outbound phone calls: Initiate phone calls programmatically from your Node.js application.

IVR: Phone Tree with Ruby and Rails

Answering a Phone Call

Respond to the Twilio request with TwiML

Respond with TwiML to gather an option from the caller

Where to send the caller's input

Send caller input to the intended route

The Main Menu: Process the caller's selection

Main menu and return instructions

The Planet Directory: Collect more input from the caller

Route users to a new phone number via the Planet Directory

Use cases for IVR phone trees with Twilio Programmable Voice

Result

Next steps