Masked Phone Numbers with Ruby and Rails

This Ruby on Rails sample application is modeled after the amazing rental experience created by AirBnB, but with more Klingons.

Host users can offer rental properties which other guest users can reserve. The guest and the host can then anonymously communicate via a disposable Twilio phone number created just for a reservation. 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.

(warning)

Legal implications of managing communications between users

If you choose to manage communications between your users, including voice calls, text-based messages (e.g., SMS), and chat, you may need to comply with certain laws and regulations, including those regarding obtaining consent. Additional information regarding legal compliance considerations and best practices for using Twilio to manage and record communications between your users, such as when using Twilio Proxy, can be found here.

Notice: Twilio recommends that you consult with your legal counsel to make sure that you are complying with all applicable laws in connection with communications you record or store using Twilio.

Read how Lyft uses masked phone numbers to let customers securely contact drivers

Create a reservation

The first step in connecting a guest and host is creating a reservation. Here, we handle a form submission for a new reservation which contains the guest's name and phone number.

Reservation Creation Method

app/controllers/reservations_controller.rb

1class ReservationsController < ApplicationController
2  skip_before_filter  :verify_authenticity_token, only: [:accept_or_reject, :connect_guest_to_host_sms, :connect_guest_to_host_voice]
3  before_action :set_twilio_params, only: [:connect_guest_to_host_sms, :connect_guest_to_host_voice]
4  before_filter :authenticate_user, only: [:index]
5
6  # GET /reservations
7  def index
8    @reservations = current_user.reservations.all
9  end
10
11  # GET /reservations/new
12  def new
13    @reservation = Reservation.new
14  end
15
16  def create
17    @vacation_property = VacationProperty.find(params[:reservation][:property_id])
18    @reservation = @vacation_property.reservations.create(reservation_params)
19
20    if @reservation.save
21      flash[:notice] = "Sending your reservation request now."
22      @reservation.host.check_for_reservations_pending
23      redirect_to @vacation_property
24    else
25      flash[:danger] = @reservation.errors
26    end
27  end
28
29  # webhook for twilio incoming message from host
30  def accept_or_reject
31    incoming = params[:From]
32    sms_input = params[:Body].downcase
33    begin
34      @host = User.find_by(phone_number: incoming)
35      @reservation = @host.pending_reservation
36      if sms_input == "accept" || sms_input == "yes"
37        @reservation.confirm!
38      else
39        @reservation.reject!
40      end
41
42      @host.check_for_reservations_pending
43
44      sms_reponse = "You have successfully #{@reservation.status} the reservation."
45      respond(sms_reponse)
46    rescue Exception => e
47      puts "ERROR: #{e.message}"
48      sms_reponse = "Sorry, it looks like you don't have any reservations to respond to."
49      respond(sms_reponse)
50    end
51  end
52
53  # webhook for twilio to anonymously connect the two parties
54  def connect_guest_to_host_sms
55    # Guest -> Host
56    if @reservation.guest.phone_number == @incoming_phone
57      @outgoing_number = @reservation.host.phone_number
58
59    # Host -> Guest
60    elsif @reservation.host.phone_number == @incoming_phone
61      @outgoing_number = @reservation.guest.phone_number
62    end
63
64    response = Twilio::TwiML::MessagingResponse.new
65    response.message(:body => @message, :to => @outgoing_number)
66    render text: response.to_s
67  end
68
69  # webhook for twilio -> TwiML for voice calls
70  def connect_guest_to_host_voice
71    # Guest -> Host
72    if @reservation.guest.phone_number == @incoming_phone
73      @outgoing_number = @reservation.host.phone_number
74
75    # Host -> Guest
76    elsif @reservation.host.phone_number == @incoming_phone
77      @outgoing_number = @reservation.guest.phone_number
78    end
79    response = Twilio::TwiML::VoiceResponse.new
80    response.play(url: "http://howtodocs.s3.amazonaws.com/howdy-tng.mp3")
81    response.dial(number: @outgoing_number)
82
83    render text: response.to_s
84  end
85
86
87  private
88    # Send an SMS back to the Subscriber
89    def respond(message)
90      response = Twilio::TwiML::MessagingResponse.new
91      response.message(body: message)
92
93      render text: response.to_s
94    end
95
96    # Never trust parameters from the scary internet, only allow the white list through.
97    def reservation_params
98      params.require(:reservation).permit(:name, :guest_phone, :message)
99    end
100
101    # Load up Twilio parameters
102    def set_twilio_params
103      @incoming_phone = params[:From]
104      @message = params[:Body]
105      anonymous_phone_number = params[:To]
106      @reservation = Reservation.where(phone_number: anonymous_phone_number).first
107    end
108
109end

Part of our reservation system is receiving reservation requests from potential renters. However, these reservations need to be confirmed. Let's see how we would handle this step.

Confirm the Reservation

Before the reservation is finalized, the host needs to confirm that the property is still available. Learn how to automate this process in our first AirTNG tutorial, Workflow Automation.

Once the reservation is confirmed, we need to create a Twilio number that the guest and host can use to communicate in the provision_phone_number method.

Confirm Reservation Method

app/models/reservation.rb

1class Reservation < ActiveRecord::Base
2  validates :name, presence: true
3  validates :guest_phone, presence: true
4
5  enum status: [ :pending, :confirmed, :rejected ]
6
7  belongs_to :vacation_property
8  belongs_to :user
9
10  def notify_host(force = false)
11    # Don't send the message if we have more than one and we aren't being forced
12    if self.host.pending_reservations.length > 1 and !force
13      return
14    else
15      message = "You have a new reservation request from #{self.name} for #{self.vacation_property.description}:
16
17      '#{self.message}'
18
19      Reply [accept] or [reject]."
20
21      self.host.send_message_via_sms(message)
22    end
23  end
24
25  def host
26    @host = User.find(self.vacation_property[:user_id])
27  end
28
29  def guest
30    @guest = User.find_by(phone_number: self.guest_phone)
31  end
32
33  def confirm!
34    provision_phone_number
35    self.update!(status: 1)
36  end
37
38  def reject!
39    self.update!(status: 0)
40  end
41
42  def notify_guest
43    if self.status_changed? && (self.status == :confirmed || self.status == :rejected)
44      message = "Your recent request to stay at #{self.vacation_property.description} was #{self.status}."
45      self.guest.send_message_via_sms(message)
46    end
47  end
48
49  def send_message_to_guest(message)
50    message = "From #{self.host.name}: #{message}"
51    self.guest.send_message_via_sms(message, self.phone_number)
52  end
53
54  def send_message_to_host(message)
55    message = "From guest #{self.guest.name}: #{message}"
56    self.host.send_message_via_sms(message, self.phone_number)
57  end
58
59  private
60
61  def provision_phone_number
62    @client = Twilio::REST::Client.new(ENV['TWILIO_ACCOUNT_SID'], ENV['TWILIO_AUTH_TOKEN'])
63    begin
64      # Lookup numbers in host area code, if none than lookup from anywhere
65      @numbers = @client.api.available_phone_numbers('US').local.list(area_code: self.host.area_code)
66      if @numbers.empty?
67        @numbers = @client.api.available_phone_numbers('US').local.list()
68      end
69
70      # Purchase the number & set the application_sid for voice and sms, will
71      # tell the number where to route calls/sms
72      @number = @numbers.first.phone_number
73      @client.api.incoming_phone_numbers.create(
74        phone_number: @number,
75        voice_application_sid: ENV['ANONYMOUS_APPLICATION_SID'],
76        sms_application_sid: ENV['ANONYMOUS_APPLICATION_SID']
77      )
78
79      # Set the reservation.phone_number
80      self.update!(phone_number: @number)
81
82    rescue Exception => e
83      puts "ERROR: #{e.message}"
84    end
85  end
86end

Once the reservation is confirmed, we need to purchase a Twilio number that the guest and host can use to communicate.

Purchase a Twilio Number

Here we use a Twilio REST API Client to search for and buy a new phone number to associate with the reservation. When we buy the number, we designate a Twilio application that will handle webhook requests when the new number receives an incoming call or text.

We then save the new phone number on our Reservation model, so when our app receives calls or texts to this number, we'll know which reservation the call or text belongs to.

Provision Phone Number Method

app/models/reservation.rb

1class Reservation < ActiveRecord::Base
2  validates :name, presence: true
3  validates :guest_phone, presence: true
4
5  enum status: [ :pending, :confirmed, :rejected ]
6
7  belongs_to :vacation_property
8  belongs_to :user
9
10  def notify_host(force = false)
11    # Don't send the message if we have more than one and we aren't being forced
12    if self.host.pending_reservations.length > 1 and !force
13      return
14    else
15      message = "You have a new reservation request from #{self.name} for #{self.vacation_property.description}:
16
17      '#{self.message}'
18
19      Reply [accept] or [reject]."
20
21      self.host.send_message_via_sms(message)
22    end
23  end
24
25  def host
26    @host = User.find(self.vacation_property[:user_id])
27  end
28
29  def guest
30    @guest = User.find_by(phone_number: self.guest_phone)
31  end
32
33  def confirm!
34    provision_phone_number
35    self.update!(status: 1)
36  end
37
38  def reject!
39    self.update!(status: 0)
40  end
41
42  def notify_guest
43    if self.status_changed? && (self.status == :confirmed || self.status == :rejected)
44      message = "Your recent request to stay at #{self.vacation_property.description} was #{self.status}."
45      self.guest.send_message_via_sms(message)
46    end
47  end
48
49  def send_message_to_guest(message)
50    message = "From #{self.host.name}: #{message}"
51    self.guest.send_message_via_sms(message, self.phone_number)
52  end
53
54  def send_message_to_host(message)
55    message = "From guest #{self.guest.name}: #{message}"
56    self.host.send_message_via_sms(message, self.phone_number)
57  end
58
59  private
60
61  def provision_phone_number
62    @client = Twilio::REST::Client.new(ENV['TWILIO_ACCOUNT_SID'], ENV['TWILIO_AUTH_TOKEN'])
63    begin
64      # Lookup numbers in host area code, if none than lookup from anywhere
65      @numbers = @client.api.available_phone_numbers('US').local.list(area_code: self.host.area_code)
66      if @numbers.empty?
67        @numbers = @client.api.available_phone_numbers('US').local.list()
68      end
69
70      # Purchase the number & set the application_sid for voice and sms, will
71      # tell the number where to route calls/sms
72      @number = @numbers.first.phone_number
73      @client.api.incoming_phone_numbers.create(
74        phone_number: @number,
75        voice_application_sid: ENV['ANONYMOUS_APPLICATION_SID'],
76        sms_application_sid: ENV['ANONYMOUS_APPLICATION_SID']
77      )
78
79      # Set the reservation.phone_number
80      self.update!(phone_number: @number)
81
82    rescue Exception => e
83      puts "ERROR: #{e.message}"
84    end
85  end
86end

Now that each reservation has a Twilio Phone Number, we can see how the application will look up reservations as guest or host calls come in.

Find a reservation when a guest or host calls

In our controller, we create a filter which gets executed every time Twilio asks our application how to handle an incoming call or text. This filter finds and stores the correct reservation (the one associated with the anonymous number) as an instance variable that will be used as we connect the guest and host via voice or SMS.

Find a Reservation

app/controllers/reservations_controller.rb

1class ReservationsController < ApplicationController
2  skip_before_filter  :verify_authenticity_token, only: [:accept_or_reject, :connect_guest_to_host_sms, :connect_guest_to_host_voice]
3  before_action :set_twilio_params, only: [:connect_guest_to_host_sms, :connect_guest_to_host_voice]
4  before_filter :authenticate_user, only: [:index]
5
6  # GET /reservations
7  def index
8    @reservations = current_user.reservations.all
9  end
10
11  # GET /reservations/new
12  def new
13    @reservation = Reservation.new
14  end
15
16  def create
17    @vacation_property = VacationProperty.find(params[:reservation][:property_id])
18    @reservation = @vacation_property.reservations.create(reservation_params)
19
20    if @reservation.save
21      flash[:notice] = "Sending your reservation request now."
22      @reservation.host.check_for_reservations_pending
23      redirect_to @vacation_property
24    else
25      flash[:danger] = @reservation.errors
26    end
27  end
28
29  # webhook for twilio incoming message from host
30  def accept_or_reject
31    incoming = params[:From]
32    sms_input = params[:Body].downcase
33    begin
34      @host = User.find_by(phone_number: incoming)
35      @reservation = @host.pending_reservation
36      if sms_input == "accept" || sms_input == "yes"
37        @reservation.confirm!
38      else
39        @reservation.reject!
40      end
41
42      @host.check_for_reservations_pending
43
44      sms_reponse = "You have successfully #{@reservation.status} the reservation."
45      respond(sms_reponse)
46    rescue Exception => e
47      puts "ERROR: #{e.message}"
48      sms_reponse = "Sorry, it looks like you don't have any reservations to respond to."
49      respond(sms_reponse)
50    end
51  end
52
53  # webhook for twilio to anonymously connect the two parties
54  def connect_guest_to_host_sms
55    # Guest -> Host
56    if @reservation.guest.phone_number == @incoming_phone
57      @outgoing_number = @reservation.host.phone_number
58
59    # Host -> Guest
60    elsif @reservation.host.phone_number == @incoming_phone
61      @outgoing_number = @reservation.guest.phone_number
62    end
63
64    response = Twilio::TwiML::MessagingResponse.new
65    response.message(:body => @message, :to => @outgoing_number)
66    render text: response.to_s
67  end
68
69  # webhook for twilio -> TwiML for voice calls
70  def connect_guest_to_host_voice
71    # Guest -> Host
72    if @reservation.guest.phone_number == @incoming_phone
73      @outgoing_number = @reservation.host.phone_number
74
75    # Host -> Guest
76    elsif @reservation.host.phone_number == @incoming_phone
77      @outgoing_number = @reservation.guest.phone_number
78    end
79    response = Twilio::TwiML::VoiceResponse.new
80    response.play(url: "http://howtodocs.s3.amazonaws.com/howdy-tng.mp3")
81    response.dial(number: @outgoing_number)
82
83    render text: response.to_s
84  end
85
86
87  private
88    # Send an SMS back to the Subscriber
89    def respond(message)
90      response = Twilio::TwiML::MessagingResponse.new
91      response.message(body: message)
92
93      render text: response.to_s
94    end
95
96    # Never trust parameters from the scary internet, only allow the white list through.
97    def reservation_params
98      params.require(:reservation).permit(:name, :guest_phone, :message)
99    end
100
101    # Load up Twilio parameters
102    def set_twilio_params
103      @incoming_phone = params[:From]
104      @message = params[:Body]
105      anonymous_phone_number = params[:To]
106      @reservation = Reservation.where(phone_number: anonymous_phone_number).first
107    end
108
109end

Next, let's see how to connect the guest and the host via SMS.

Connect the Guest and the Host via SMS

Our Twilio application should be configured to send HTTP requests to this controller method on any incoming text message. Our app responds with TwiML to tell Twilio what to do in response to the message.

If the initial message sent to the anonymous number was made by the host, we forward it on to the guest. But if the message was sent by the guest, we forward it to the host.

Connect Via SMS

app/controllers/reservations_controller.rb

1class ReservationsController < ApplicationController
2  skip_before_filter  :verify_authenticity_token, only: [:accept_or_reject, :connect_guest_to_host_sms, :connect_guest_to_host_voice]
3  before_action :set_twilio_params, only: [:connect_guest_to_host_sms, :connect_guest_to_host_voice]
4  before_filter :authenticate_user, only: [:index]
5
6  # GET /reservations
7  def index
8    @reservations = current_user.reservations.all
9  end
10
11  # GET /reservations/new
12  def new
13    @reservation = Reservation.new
14  end
15
16  def create
17    @vacation_property = VacationProperty.find(params[:reservation][:property_id])
18    @reservation = @vacation_property.reservations.create(reservation_params)
19
20    if @reservation.save
21      flash[:notice] = "Sending your reservation request now."
22      @reservation.host.check_for_reservations_pending
23      redirect_to @vacation_property
24    else
25      flash[:danger] = @reservation.errors
26    end
27  end
28
29  # webhook for twilio incoming message from host
30  def accept_or_reject
31    incoming = params[:From]
32    sms_input = params[:Body].downcase
33    begin
34      @host = User.find_by(phone_number: incoming)
35      @reservation = @host.pending_reservation
36      if sms_input == "accept" || sms_input == "yes"
37        @reservation.confirm!
38      else
39        @reservation.reject!
40      end
41
42      @host.check_for_reservations_pending
43
44      sms_reponse = "You have successfully #{@reservation.status} the reservation."
45      respond(sms_reponse)
46    rescue Exception => e
47      puts "ERROR: #{e.message}"
48      sms_reponse = "Sorry, it looks like you don't have any reservations to respond to."
49      respond(sms_reponse)
50    end
51  end
52
53  # webhook for twilio to anonymously connect the two parties
54  def connect_guest_to_host_sms
55    # Guest -> Host
56    if @reservation.guest.phone_number == @incoming_phone
57      @outgoing_number = @reservation.host.phone_number
58
59    # Host -> Guest
60    elsif @reservation.host.phone_number == @incoming_phone
61      @outgoing_number = @reservation.guest.phone_number
62    end
63
64    response = Twilio::TwiML::MessagingResponse.new
65    response.message(:body => @message, :to => @outgoing_number)
66    render text: response.to_s
67  end
68
69  # webhook for twilio -> TwiML for voice calls
70  def connect_guest_to_host_voice
71    # Guest -> Host
72    if @reservation.guest.phone_number == @incoming_phone
73      @outgoing_number = @reservation.host.phone_number
74
75    # Host -> Guest
76    elsif @reservation.host.phone_number == @incoming_phone
77      @outgoing_number = @reservation.guest.phone_number
78    end
79    response = Twilio::TwiML::VoiceResponse.new
80    response.play(url: "http://howtodocs.s3.amazonaws.com/howdy-tng.mp3")
81    response.dial(number: @outgoing_number)
82
83    render text: response.to_s
84  end
85
86
87  private
88    # Send an SMS back to the Subscriber
89    def respond(message)
90      response = Twilio::TwiML::MessagingResponse.new
91      response.message(body: message)
92
93      render text: response.to_s
94    end
95
96    # Never trust parameters from the scary internet, only allow the white list through.
97    def reservation_params
98      params.require(:reservation).permit(:name, :guest_phone, :message)
99    end
100
101    # Load up Twilio parameters
102    def set_twilio_params
103      @incoming_phone = params[:From]
104      @message = params[:Body]
105      anonymous_phone_number = params[:To]
106      @reservation = Reservation.where(phone_number: anonymous_phone_number).first
107    end
108
109end

Let's see how to connect the guest and the host via phone call next.

Connect the Guest and Host via Phone Call

Our Twilio application will send HTTP requests to this method on any incoming voice call. Our app responds with TwiML instructions that tell Twilio to Play an introductory MP3 audio file and then Dial either the guest or host, depending on who initiated the call.

Connect Via Phone Call

app/controllers/reservations_controller.rb

1class ReservationsController < ApplicationController
2  skip_before_filter  :verify_authenticity_token, only: [:accept_or_reject, :connect_guest_to_host_sms, :connect_guest_to_host_voice]
3  before_action :set_twilio_params, only: [:connect_guest_to_host_sms, :connect_guest_to_host_voice]
4  before_filter :authenticate_user, only: [:index]
5
6  # GET /reservations
7  def index
8    @reservations = current_user.reservations.all
9  end
10
11  # GET /reservations/new
12  def new
13    @reservation = Reservation.new
14  end
15
16  def create
17    @vacation_property = VacationProperty.find(params[:reservation][:property_id])
18    @reservation = @vacation_property.reservations.create(reservation_params)
19
20    if @reservation.save
21      flash[:notice] = "Sending your reservation request now."
22      @reservation.host.check_for_reservations_pending
23      redirect_to @vacation_property
24    else
25      flash[:danger] = @reservation.errors
26    end
27  end
28
29  # webhook for twilio incoming message from host
30  def accept_or_reject
31    incoming = params[:From]
32    sms_input = params[:Body].downcase
33    begin
34      @host = User.find_by(phone_number: incoming)
35      @reservation = @host.pending_reservation
36      if sms_input == "accept" || sms_input == "yes"
37        @reservation.confirm!
38      else
39        @reservation.reject!
40      end
41
42      @host.check_for_reservations_pending
43
44      sms_reponse = "You have successfully #{@reservation.status} the reservation."
45      respond(sms_reponse)
46    rescue Exception => e
47      puts "ERROR: #{e.message}"
48      sms_reponse = "Sorry, it looks like you don't have any reservations to respond to."
49      respond(sms_reponse)
50    end
51  end
52
53  # webhook for twilio to anonymously connect the two parties
54  def connect_guest_to_host_sms
55    # Guest -> Host
56    if @reservation.guest.phone_number == @incoming_phone
57      @outgoing_number = @reservation.host.phone_number
58
59    # Host -> Guest
60    elsif @reservation.host.phone_number == @incoming_phone
61      @outgoing_number = @reservation.guest.phone_number
62    end
63
64    response = Twilio::TwiML::MessagingResponse.new
65    response.message(:body => @message, :to => @outgoing_number)
66    render text: response.to_s
67  end
68
69  # webhook for twilio -> TwiML for voice calls
70  def connect_guest_to_host_voice
71    # Guest -> Host
72    if @reservation.guest.phone_number == @incoming_phone
73      @outgoing_number = @reservation.host.phone_number
74
75    # Host -> Guest
76    elsif @reservation.host.phone_number == @incoming_phone
77      @outgoing_number = @reservation.guest.phone_number
78    end
79    response = Twilio::TwiML::VoiceResponse.new
80    response.play(url: "http://howtodocs.s3.amazonaws.com/howdy-tng.mp3")
81    response.dial(number: @outgoing_number)
82
83    render text: response.to_s
84  end
85
86
87  private
88    # Send an SMS back to the Subscriber
89    def respond(message)
90      response = Twilio::TwiML::MessagingResponse.new
91      response.message(body: message)
92
93      render text: response.to_s
94    end
95
96    # Never trust parameters from the scary internet, only allow the white list through.
97    def reservation_params
98      params.require(:reservation).permit(:name, :guest_phone, :message)
99    end
100
101    # Load up Twilio parameters
102    def set_twilio_params
103      @incoming_phone = params[:From]
104      @message = params[:Body]
105      anonymous_phone_number = params[:To]
106      @reservation = Reservation.where(phone_number: anonymous_phone_number).first
107    end
108
109end

That's it! We've just implemented anonymous communications that allow your customers to connect while protecting their privacy with the help of the Twilio Ruby Helper Library.

Where to Next?

If you're a Ruby developer working with Twilio, you might want to check out these other tutorials.

Part 1 of this Tutorial: Workflow Automation

Increase your rate of response by automating the workflows that are key to your business.

Appointment Reminders

Send your customers a text message when they have an upcoming appointment - this tutorial shows you how to do it from a background job.

Did this help?

Thanks for checking out this tutorial! If you have any feedback to share with us, we'd love to hear it. Tweet @twilio to let us know what you think.