Google Dialogflow Integration

An Express app that responds with TwiML to <Connect> to a MediaStream and connect it with a specified Dialogflow.

Prerequisites

• Setup a Dialogflow Agent and make note of the Google Project ID
• Download your Google Credentials (that has access to your Dialogflow project) to a file named google_creds.json store that in the root of this folder.
• Optional: Setup and Configure the gcloud command line tool so that you can deploy to Google AppEngine

Installation

npm install

Populate your .env file from the .env.example file using configure-env

npx configure-env

Install the Twilio CLI

Optional: Purchase a Twilio number (or use an existing one)

Optional: Search for available numbers in the 650 area code in the US

twilio api:core:available-phone-numbers:local:list  --area-code="650" --country-code=US --voice-enabled

Optional: Buy a number

twilio api:core:incoming-phone-numbers:create --phone-number="+16505551234"

Develop locally

Start the server locally

npm start

Wire up your Twilio number with your endpoint on incoming calls. This will automatically start an ngrok tunnel to your machine.

twilio phone-numbers:update +15552223333 --voice-url=http://localhost:3000/twiml

Deploy to AppEngine

gcloud app deploy

Point your Incoming Webhook to your AppEngine instance.

twilio phone-numbers:update +15552223333 --voice-url=https://YOUR-APPENGINE-INSTANCE.appspot.com/twiml

Capture Intent after End of Interaction

If you set END_OF_INTERACTION_URL in your .env file to a Webhook that you host, you can handle events. You will receive dialogflowJSON as a querystring on your Webhook.

The JSON will contain the Intent's information for you to code your response.

Here is an example using a Twilio Function:

exports.handler = function(context, event, callback) {
  const twiml = new Twilio.twiml.VoiceResponse();
  const dialogflow = JSON.parse(event.dialogflowJSON);
  switch (dialogflow.intent.displayName) {
    case 'speak-to-an-agent':
      console.log(`Dialing agent number configured in environment: ${process.env.AGENT_NUMBER}`);
      twiml.dial(process.env.AGENT_NUMBER);
      break;
    default:
      console.error(`Intent: "${dialogflow.intent.displayName}" (${dialogflow.intent.name}) was not handled.`);
      twiml.hangup();
  }
  callback(null, twiml);
}