Using Cloud Storage for Firebase for hosting rich media in your Actions

index.js

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
const bucket = admin.storage().bucket();
const bucketAccessConfig = {
  action: 'read',
  expires: Date.now() + 1000 * 60 * 60
};

const {dialogflow, Image, MediaObject} = require('actions-on-google');

const app = new dialogflow();

app.intent('media response', async conv => {
    const mediaFileRef = bucket.file('audio/long-audio.mp3');
    const [mediaUrl] = await mediaFileRef.getSignedUrl(bucketAccessConfig);

    const iconFileRef = bucket.file('icons/long-audio-icon.png');
    const [iconUrl] = await iconFileRef.getSignedUrl(bucketAccessConfig);  

    conv.ask('Here is a media response');
    conv.ask(new MediaObject({
        name: 'My Media Object',
        url: mediaUrl,
        description: 'A funky beat',
        icon: new Image({
            url: iconUrl,
            alt: 'Media icon'
        });
     }));
});

exports.fulfillment = functions.https.onRequest(app);