06 Apr Building an interactive voicemail application using Restcomm Visual Designer

The Restcomm Visual Designer (RVD) is a tool for building smart voice, SMS and conferencing applications, using simple drag & drop interface. To showcase some of the available functionality in the RVD, we will start with a very simple interactive voicemail application which is aimed solely to demonstrate how to make use of some of the key building blocks, such as the Text-To-Speech, Voice Recording and Recording Playback functionality.

The application in this tutorial is a simple voicemail app. It is triggered when you ring a specific number, which you will provision and then:

• Prompts you to leave a message after the tone
• Records your voice message
• Plays back the message you recorded.

How it works

1. You get a number
2. You create an RVD app with the following steps:
   • Uses text-to-speech to instruct caller to leave a voice message.
   • Records voice message
   • Plays back message that was recorded.
3. You link the RVD application to the registered number

How to build

1. Get yourself a number
   • If you don’t have any Numbers yet, click on “Register Number”
   • Switch to “Provider Number” tab, so you can provision a real number
   • Select your country from the dropdown list. If applicable, select an Area Code as well.
   • Click the “Register Number” button on the right-hand side of the number you would like to register under your account.
     
2. Build the RVD app:
   • We will need two modules. One for recording and one for playing back the audio message. Let’s create a second module – titled “Playback”.
   • Drag a “Say” action into the Welcome module. This is the Text-To-Speech functionality.
     
     • Type in some text in the box to instruct the user to leave a message.
       
   • Now, onto the actual recording. Drag a “Record” action below the “Say” action

1. • Let’s move to the “Playback” module:
     • In the “Continue to” dropdown, select the “Playback” module.
     • In the “Play beep” dropdown, select “Yes”, as is customary to do for voicemail.
     • You might also want to edit some of the more advanced options, such as maximum recording time, and how the recording ends, by clicking the gear icon.
   • Let’s move to the “Playback” module:
   • Drag a “Say” action, with some text that confirms recording is complete and that the message will now be played back.
   • Drag a “Play” action, which is what is used for playing back audio files. This action can be used to play back any audio file you upload into the Restcomm Visual Designer, or one that is available on a publicly accessible URL.
     • To play back the previous voice recording, we will use the URL option, and insert a special variable, provided by the Restcomm Visual Designer as the public URL where the recording is made available: `$core_PublicRecordingUrl` and use this as the value of the field.
       
   • Finally, you can end your module with another “Say” action, which confirms to the caller that the scenario is finished.

3. Connect your RVD app to your registered phone number

• Go back to Numbers
• Navigate to the number you registered
• Choose your application from the Voice request drop down
• Save your changes

Now you have a simple version of a voicemail application ready to use.

If you want to see a more advanced voicemail and IVR application built on RVD, take a look at our Restcomm Marketplace partner, Voxist.

If you want to try this out for yourself, sign up for a trial account.