Dial Status Reporting Using PHP

If you still wish to implement dial status reporting in the traditional API/XML way, you can refer to the instructions in the following section to begin your implementation.

Outline

Implementation

In this section, we will guide you in setting up an dial status reporting app on your Plivo number. In this example, when an incoming call is received, the call will be forwarded as the XML returned from your answer_url will be a <dial> XML. Once the destination number(s) amswers the call, the status of the call will be sent to your app server. This example uses an action URL in the Dial XML. After completion of the call, Plivo will report back the status to this URL. You can control the call flow by returning a valid Plivo XML from the action URL and setting the redirect attribute as “true”. In this example, Plivo will POST the call status to http://foo.com/dialstatus/action/ and expects a valid XML since the redirect attribute is set to “true”.

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 Laravel Server for Incoming Calls & Callbacks section.

Set Up Laravel server for Incoming Calls & Callbacks.

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

Install PHP

Install Composer

Composer is a dependency manager for PHP that is used in all modern PHP frameworks, such as Symfony and Laravel. We highly recommend using Composer as the package manager for your web project.

Install Laravel & Create a Laravel Project

• Use the below command to install Laravel:

  $ composer require laravel/installer
  

As we have Laravel and its dependencies installed, we can use them to create a new Laravel project. As the initial step, using Laravel we can auto-generate code in the Laravel folder structure.

• Change the directory to our project directory in the command line:

  $ cd mylaravelapp
  

• Use the below command to start your Laravel project:

  $ composer create-project laravel/laravel quickstart --prefer-dist
  

• To install the stable release, run the following command in the project directory:

  $ composer require plivo/plivo-php
  

This will create a quickstart directory with the necessary folders & files for development.

Install Plivo

• To install a specific release, run the following command in the project directory:

  $ composer require plivo/plivo-php:4.15.0
  

• Alternatively, you can download this source and run

  $ composer install
  

This generates the autoload files, which you can include using the following line in your PHP source code to start using the SDK.

<?php
require 'vendor/autoload.php'

Create a Laravel Controller for Dial Status Reporting

Change the directory to our newly created project directory, i.e, quickstart directory and run the below command to create a Laravel controller to screen incoming calls.

$ php artisan make:controller VoiceController

This will generate a controller named VoiceController in the app/http/controllers/ directory. Now, You have to open the app/http/controllers/voiceController.php file and add the following code:

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<?php

namespace App\Http\Controllers;
require '../../vendor/autoload.php';
use Plivo\RestClient;
use Plivo\XML\Response;
use Illuminate\Http\Request;

class VoiceController extends Controller
{
    // Speak XML to handle your first incoming call
    public function dialStatus()
    {
      $r = new Response();
      // Add Speak tag
      $body = "Connecting your call..";
      $r->addSpeak($body);
      $params = array(
         'action' => 'https://example.com/dial_action/', # Redirect to this URL after leaving Dial.
         'method' => 'GET' # Submit to action URL using GET or POST.
      );
      // Add Dial tag
      $d = $r->addDial($params);
      $number = "+15671234567";
      $d->addNumber($number);
      Header('Content-type: text/xml');
      echo($r->toXML());
    }
    // Action URL Block
    public function dialstatusAction()
    {
      // Print the Dial Details
      $status = $_REQUEST['DialStatus'];
      $aleg = $_REQUEST['DialALegUUID'];
      $bleg = $_REQUEST['DialBLegUUID'];
      echo "Status = $status , Aleg UUID = $aleg , Bleg UUID = $bleg";
    }
}

Add a Route

Now, you need to add a route for the dialStatus function in VoiceController class, open the routes/web.php file and add the below line at the end of the file:

Route::match(['get', 'post'], '/dialstatus', 'VoiceController@dialStatus');
Route::match(['get', 'post'], '/dial_action', 'VoiceController@dialstatusAction');

Now the VoiceController is ready to dial out to the number specified in the Dial element and to track dial status reporting, you can use the below command to handle your inbound calls using Laravel and Plivo PHP SDK.

$ php artisan serve

Your local development server will be started and you can test the laravel app for inbound calls via the URL http://127.0.0.1:8000/dialstatus/.

Exposing your local server to the internet

To receive incoming calls and to handle callbacks, your local server should be able to connect with the 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 that can talk to the Plivo server.

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 8000, run the following command:

$ ./ngrok http 8000

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.

You can check the app in action on https://ff3e00858d94.ngrok.io/dialstatus.

Create a Plivo Application

1. Create an Application by visiting the Application Page and click on New Application. You can also use Plivo’s Application API.
2. Give your application a name. Let’s call it Dial Status Report. Enter your server URL (e.g. http://example.com/dialstatus/) in the Answer URL field and set the method as POST. See our Application API docs to learn how to modify your application through our APIs.
3. Click on Create to save your application.

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 Dial Status Report (name of the app) from the Plivo App dropdown list.
3. Click on Update to save.

Test and validate

Call the Plivo phone number assigned to your app. The calls will be forwarded to the number specified in the dial XML app, also, the call details will be posted to your application server during different call statuses.