Streaming Audio into a Call with Node.js

This is the sample code for the Streaming Audio into a Call with Node.js blog post. This project showcases how to stream audio into a call using Node.js. It uses the Vonage Server SDK to make a call to a specified number, then streams audio into the call.

Prerequisites

• Node.js and npm installed.
• A Vonage account with a Voice API application and linked number.
• Ngrok installed and set up.
• A public domain music file.

Setup and Installation

Follow the steps below to set up and run this application:

1. Create a Voice API application: Use your Vonage account to create a new voice app. Link an existing number to it, or purchase a new one. Note down the application id.

2. Download the private key: Download the private key associated with your voice app to your application directory.

3. Start an ngrok tunnel: Run ngrok http 3000 in your terminal to start an ngrok tunnel.

4. Update the silence.mp3 URL: In the /public/answer.json file, change the hostname of the silence.mp3 URL to match your ngrok hostname.

5. Configure environment variables: Rename the example.env file to .env and update the variables with your API key, secret, private key file path, and your ngrok URL. Also, specify the 'to' and 'from' numbers for making the call.

6. Install dependencies: Run npm install in your terminal from the root directory of the project.

7. Start the application: Run node server.js to start the app.

Usage

To initiate a call, make a GET request to http://localhost:3000/call. This will call the configured TO_NUMBER.

If all goes well, you will first hear a message, followed by silence. After a few seconds, music will play for 30 seconds and then stop.

Note: The music file this application uses (City Sunshine by Kevin MacLeod) is in the public domain. For more information, visit FreePD.