Get Started with IVR Using Go

    Overview

    Interactive voice response (IVR) systems let incoming callers access information and find contacts via a menu of prerecorded messages, without having to speak to an agent, and let you automate polling via outgoing calls. Callers and call recipients can respond to prompts via Touch-Tone keypad presses or speech recognition. IVR systems can handle larger call volumes than operators and reduce costs associated with customer service.

    Common IVR use cases include:

    • Auto-attendant: You can replace a receptionist with an IVR system that routes calls to agents during business hours and accepts voicemail when no one is available.
    • Call center: You can route calls coming in to call centers to the appropriate representatives based on user input.
    • Surveys, polling, and voting: You can implement IVR in outbound calls to collect customer satisfaction scores or conduct political polling.
    • Appointment reminders: You can send automated reminders to customers before their scheduled visits to help avoid missed appointments and facilitate rescheduling.
    • Lead assignment and lead routing: For inbound sales calls, you can set up an IVR menu with a set of qualifying questions to discover a customer’s interests, then redirect their call to a representative based on their responses.

    This guide shows how to build an IVR menu system on the Plivo platform, either by using our PHLO visual workflow builder or our APIs and XML documents. Follow the instructions in one of the tabs below.

    To implement Phone System IVR use-case, you can create and deploy a PHLO with a few clicks on the PHLO canvas. PHLO also lets you visually construct your entire use-case. With PHLO, you only pay for calls you make/receive, and building with PHLO is free.

    Note: When you create a PHLO application to handle the incoming calls to your Plivo number(s), you don't have to write a single line of code because you will define the instructions to manage the call flow of the incoming calls on the PHLO itself.

    Outline

    Implementation

    In this section, we will guide you to create a PHLO to implement Phone System IVR use-case.

    Prerequisites

    1. Create a Plivo Account(if you don’t have one already): You can sign up with your work email address and complete the phone verification step using your mobile number.
    2. Buy a Plivo number: You must have a voice-enabled Plivo phone number to receive incoming calls. You can purchase numbers from the Numbers section of your Plivo Console. It is also possible to purchase numbers using the Numbers API.
    3. PHLO Application: When you receive a call on a Plivo voice-enabled number, you can control the call flow by associating a PHLO application to that Plivo phone number. Plivo will fetch the PHLO associated with the number and expect valid instructions via PHLO to handle the call.

    Create the PHLO

    1. On the top navigation bar, click PHLO. The PHLO page will appear and display your existing PHLOs, if any. If this is your first PHLO, then the PHLO page will be empty.
    2. Click CREATE NEW PHLO to build a new PHLO.
    3. On the Choose your use-case window, click Build my own. The PHLO canvas will appear with the Start node. Note: The Start node is the starting point of any PHLO. You can choose between the four available trigger states of the Start node; Incoming SMS, Incoming Call, Endpoint Call, and API Request. For this PHLO, we will use the Incoming Call trigger state.
    4. From the list of components, on the left hand side, drag and drop the IVR Menu component onto the canvas. This will add an IVR Menu node onto the canvas.
    5. Connect the Start node with the IVR Menu node, using the Incoming Call trigger state. Note: Make sure to configure the choices for the IVR Menu from the Configurations tab. In this example, we will select 1 and 2 as the allowed choices and enter a message to play to the user.
    6. Click Validate to add 1 and 2 trigger states to the IVR Menu.
    7. Configure No_Input_Prompt and Invalid_Input_Prompt nodes to speak a fixed message in case of a wrong input or no input.
    8. Click Validate to save the configurations for the node.
    9. Next, create two nodes for the Call Forward component and rename them as Connect_to_Support and Connect_to_Sales . Note: You can rename the nodes as per your requirements. We are using specific names in this example to help you relate to the different nodes used in this use case.
    10. Connect Connect_to_Support and Connect_to_Sales nodes to the IVR Menu using the 1 and 2 trigger states.
    11. Similarly, create two nodes for the Play Audio component.
    12. Connect Play Audio_1 and Play Audio_2 nodes to the IVR Menu using the No Input and Wrong Input trigger states.
    13. Rename Play Audio_1 to No_Input_Prompt. Note: You can rename the nodes as per your requirements. We are using specific names to help you relate to the different nodes used in this use case.
    14. Rename Play Audio_2 to Invalid_Input_Prompt.
    15. Connect the Prompt Completed trigger state of No_Input_Prompt and Invalid_Input_Prompt nodes to the IVR Menu. This will send the user back to the IVR Menu if they press an incorrect option, or if they do not press any key.
    16. Configure the Call Forward nodes to select the From number using a variable. For the To number, you can either enter a fixed number directly into the To field, or use a variable configured in the Start node Note: Enter two curly brackets to view all available variables.
    17. Rename Call Forward_1 to Connect_to_Support, and Call Forward_2 to Connect_to_Sales.
    18. Click Validate to save the configurations for the node.
    19. After you complete the configurations, click Save. Your PHLO is now ready. Link the PHLO to a Plivo Phone Number and test it out. For more information, see Adding the PHLO to a Phone Number.

    Your complete PHLO will look like this:

    Phone System IVR

    Assign the PHLO to a Plivo Number for Incoming Calls

    Once you have created and configured your PHLO, assign your PHLO to a Plivo number.

    To assign a PHLO to a number:

    1. Login to your Plivo Console
    2. On the Product Navigation bar, click Phone Numbers.
    3. On the Numbers page, under Your Numbers, click the phone number you wish to use for the PHLO.
    4. In the Number Configuration window, select PHLO from the Application Type list.
    5. From the PHLO Name list, select the PHLO you wish to use with the phone number, and then click Update Number.

    Assign PHLO to a Plivo Number

    If you have not purchased a phone number yet, you can buy Phone number(s) by referring to the instructions available here.

    Test and Validate

    You can now make a call to your Plivo phone number to receive an incoming call and see how the Phone System IVR implementation is working using PHLO.

    For more information about creating a PHLO app, see the PHLO User Guide.
    For information on components and their variables, see the PHLO Components Library.

    To implement Phone System IVR use-case in the traditional XML way, you can refer to the instructions in the following section to begin your implementation.

    Outline

    Phone System IVR- Call Flow

    Implementation

    In this section, we will guide you in setting up an app to receive a call on your Plivo number and add the caller(s) to a IVR Phone Menu using Plivo XML. In this example, when an incoming call is received, Plivo will add the caller(s) to the IVR using the <GetInput> XML.

    Prequisites

    1. Create a Plivo Account (if you don’t have one already): You can Sign up with your work email address and complete the phone verification step using your mobile number.
    2. Buy a Plivo Number: You must have a voice-enabled Plivo phone number if you are willing to receive incoming calls. You can purchase numbers from the Numbers section of your Plivo Console. It is also possible to purchase numbers using the Numbers API.
    3. Answer URL & Callback URLs: When a call is received on a Plivo voice-enabled number, you can control the call flow by declaring an answer URL for your Plivo application associated with that Plivo phone number. Plivo will invoke the answer URL specified and expect a valid XML response to handle the call.

      Notice how the concept of Answer URLs applies to both outbound API calls as well as incoming calls to your Plivo numbers. In the outbound API call example in the Make-Outbound-Calls use-case guide, we specified the answer URL along with the make call API request, whereas in the case of incoming calls to Plivo numbers, the answer URL is specified in the Plivo application associated with the phone number.

      In addition to requests to the answer URL, Plivo initiates HTTP requests to your application server through the course of a call based on the specific XML elements in your answer XML. Such requests can be broadly classified into two categories:

      Action URL requests: XML instructions to carry forward the call are expected in response to these requests. These requests are typically invoked at the end of an XML element’s execution. For example: when an IVR input is received from the caller during a GetInput XML execution.

      Callback URL requests: No XML instructions are expected in response to these requests. Such requests serve as webhooks to notify your application server of important events through the course of an XML element’s execution. For example: when a conference participant is muted or unmuted.

    4. Set Up Your Web Server: To be able to host Answer and Callback URLs and to be able to provide valid XMLs and accept notifications on these URLs respectively, you need to host a webserver at your end. To set up your Web Server in your preferred programming language, please refer to the instructions available in the Set Up Go Server for Incoming Calls & Callbacks section.

    Set Up Go Server for Incoming Calls & Callbacks

    In this section, we’ll walk you through how to set up a Go server in under five minutes and start handling incoming calls & callbacks.

    Install Go

    You can install Go from the Official Installer.

    Install Plivo Go Package

    • Create a project directory, run the following command:

      $ mkdir mygoapp
      
    • Change the directory to our project directory in the command line:

      $ cd mygoapp
      
    • You can install the Plivo Go package using the go command.

      $ go get github.com/plivo/plivo-go
      
    • You can also install by cloning this repository into your GOPATH.

    Create a Go Server to Implement Phone System IVR

    Use the following code snippet to start a local server.

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    package main
    
    import (
    	"github.com/go-martini/martini"
    	"github.com/plivo/plivo-go/xml"
    	"net/http"
    )
    
    func main() {
    	m := martini.Classic()
    	const
    	(
    	// This file will be played when a caller presses 2.
    	PlivoSong = "https://s3.amazonaws.com/plivocloud/music.mp3"
    	// This is the message that Plivo reads when the caller dials in
    	IvrMessage1 = "Welcome to the Plivo IVR Demo App. Press 1 to listen to a pre recorded text in different languages. Press 2 to listen to a song."
    	IvrMessage2 = "Press 1 for English. Press 2 for French. Press 3 for Russian"
    	// This is the message that Plivo reads when the caller does nothing at all
    	NoInputMessage = "Sorry, I didn't catch that. Please hangup and try again later."
    	// This is the message that Plivo reads when the caller inputs a wrong number.
    	WrongInputMessage = "Sorry, it's wrong input."
    	)
    
    	m.Post("/ivr/", func(w http.ResponseWriter, r *http.Request) string {
    		w.Header().Set("Content-Type", "application/xml")
    		response := xml.ResponseElement{
    			Contents: []interface{}{
    				new(xml.GetInputElement).
    				SetAction("https://www.foo.com/ivr/firstbranch/").
    				SetMethod("POST").
    				SetDigitEndTimeout(5).
    				SetInputType("dtmf").
    				SetRedirect(true).
    				SetContents([]interface{}{new(xml.SpeakElement).
    					AddSpeak(IvrMessage1),
    					}),
    				new(xml.SpeakElement).
    					AddSpeak(NoInputMessage),
    			},
    		}
    		return response.String()
    	})
    
    	m.Post("/ivr/firstbranch/", func(w http.ResponseWriter, r *http.Request) string {
    	w.Header().Set("Content-Type", "application/xml")
    	digit := r.FormValue("Digits")
    	if digit == "1" {
    		return xml.ResponseElement{
    			Contents: []interface{}{
    				new(xml.GetInputElement).
    				SetAction("https://www.foo.com/ivr/firstbranch/").
    				SetMethod("POST").
    				SetDigitEndTimeout(5).
    				SetInputType("dtmf").
    				SetRedirect(true).
    				SetContents([]interface{}{new(xml.SpeakElement).
    					AddSpeak(IvrMessage2),
    					}),
    				new(xml.SpeakElement).
    					AddSpeak(NoInputMessage),
    			},
    		}.String()
    	} else if digit == "2" {
    		return xml.ResponseElement{
    			Contents: []interface{}{
    				new(xml.PlayElement).
    					AddSpeak(PlivoSong),
    			},
    		}.String()
    	} else {
    		return xml.ResponseElement{
    			Contents: []interface{}{
    				new(xml.SpeakElement).
    					AddSpeak(WrongInputMessage),
    				},
    			}.String()
    		}
    	})
    
    	m.Post("/ivr/secondbranch/", func(w http.ResponseWriter, r *http.Request) string {
    		w.Header().Set("Content-Type", "application/xml")
    		digit := r.FormValue("Digits")
    		if digit == "1" {
    			return xml.ResponseElement{
    				Contents: []interface{}{
    					new(xml.SpeakElement).
    						SetLanguage("en-GB").
    						AddSpeak("This message is being read out in English"),
    					},
    				}.String()
    		} else if digit == "2" {
    			return xml.ResponseElement{
    				Contents: []interface{}{
    					new(xml.SpeakElement).
    						SetLanguage("fr-FR").
    						AddSpeak("Ce message est lu en français"),
    					},
    			}.String()
    		} else if digit == "3" {
    		return xml.ResponseElement{
    			Contents: []interface{}{
    				new(xml.SpeakElement).
    					SetLanguage("ru-RU").
    					AddSpeak("Это сообщение было прочитано в России"),
    				},
    			}.String()
    		} else {
    			return xml.ResponseElement{
    				Contents: []interface{}{
    					new(xml.SpeakElement).
    						AddSpeak(WrongInputMessage),
    					},
    			}.String()
    		}
    		})
    	m.Run()
    }
    

    Save this code in any file (name the file something like ivr.go). To run this file on the server, go to the folder where this file resides and use the following command:

    $ go run ivr.go
    

    And you should see your basic server app in action on http://localhost:8080/ivr/

    Exposing your local server to the internet

    To receive Incoming Calls and to handle callbacks, your local server should be able to connect with Plivo API service, Ngrok is a tunneling software used to expose a web server running on your local machine to the internet. Using Ngrok you can set webhooks which can talk to Plivo server.

    ngrok block diagram

    You can download and install ngrok from here. Follow the detailed configuration instructions to get started.

    Run ngrok on the port which currently hosts your application. For example, if your port number is 80, run the following command:

    ./ngrok http <port_on_which_your_local_server_is_running>
    

    This will give you a UI with links that look like ngrok.io/* which you can use to access your local server using the public network.

    Sample ngrok CLI

    Create a Plivo Application

    1. Create an Application by visiting the Application Page and click on New Application or by using Plivo’s Application API.
    2. Give your application a name. Let’s call it Phone IVR. Enter your server URL (e.g., http://www.example.com/response/ivr) in the Answer URL field and set the method as GET. See our Application API docs to learn how to modify your application through our APIs.
    3. Click on Create Application to save your application.

    Plivo Create Application Phone IVR

    Assign a Plivo number to your app

    1. Navigate to the Numbers page and select the phone number you want to use for this app.
    2. Select Phone IVR (name of the app) from the Plivo App dropdown list.
    3. Click on ‘Update Number’ to save.

    Assign Application Phone IVR

    Test and validate

    You can now make a call to your Plivo phone number to receive an incoming call and see how the Phone System IVR implementation is working using Plivo XML.