Add a Receive Call Route

You will now provide an answer webhook so that when you receive an inbound call on your virtual number, the Vonage API platform will notify you on that webhook via an HTTP request.

The webhook will return an NCCO to Vonage containing a single stream action, which will play the audio from the file located at the STREAM_URL into the call.

For testing purposes you will use the URL: https://raw.githubusercontent.com/nexmo-community/ncco-examples/gh-pages/assets/welcome_to_nexmo.mp3

Add the following code to the VoiceController class

[HttpGet("/webhooks/answer")]
public string Answer()
{
    const string STREAM_URL = "https://raw.githubusercontent.com/nexmo-community/ncco-examples/gh-pages/assets/welcome_to_nexmo.mp3";
    var streamAction = new StreamAction{
        StreamUrl = new string[]
        {
            STREAM_URL
        }
    };
    var ncco = new Ncco(streamAction);
    return ncco.ToString();
}