Ytukyg

I need to get the email address from Google user's profile.

I'm using Dialogflow and I implemented google-sign-in procedure to get the Client ID (issued by Google to your Actions), and I'm also fulfilling actions.intent.SIGN_IN intent (as explained here). I do receive the Google ID token that contains the user's Google profile information, the problem is about decoding the token.

If I were using Actions on Google client library for Node.js, I could just follow the example from google-sign-in authentication flow:

If you use the Actions on Google client library for Node.js, it takes care of validating and decoding the token for you, and gives you access to the profile content, as shown in the following code snippet:

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

const app = dialogflow({

  // REPLACE THE PLACEHOLDER WITH THE CLIENT_ID OF YOUR ACTIONS PROJECT

  clientId: CLIENT_ID,

})



// Intent that starts the account linking flow.

app.intent('Start Signin', conv => {

  conv.ask(new SignIn('To get your account details'))

})



// Create a Dialogflow intent with the `actions_intent_SIGN_IN` event.

app.intent('Get Signin', (conv, params, signin) => {

  if (signin.status === 'OK') {

    const payload = conv.user.profile.payload

    conv.ask(`I got your account details, ${payload.name}. What do you want to do next?`)

  } else {

    conv.ask(`I won't be able to save your data, but what do you want to do next?`)

  }

})

The problem is that I'm using Dialogflow Fulfillment Library (because I'm working with Google Assistant and with other integrations as well).

From their sample code, I'm following this approach using the WebhookClient:

const functions = require('firebase-functions');

const { WebhookClient } = require('dialogflow-fulfillment');



function someIntent(agent) {

  if (agent.requestSource === agent.ACTIONS_ON_GOOGLE) {

    // let conv = agent.conv( );

    // do some google specific stuff... conv.ask( ... );

    agent.add('You came from Actions on Google');

  } else {

    agent.add('You came from any other source...');

  }

}



exports.dialogflowFirebaseFulfillment = functions.https.onRequest((request, response) => {

  const agent = new WebhookClient({ request, response });

  let intentMap = new Map( );

  intentMap.set('some-intent', someIntent);

  agent.handleRequest(intentMap);

});

So, the question is: Is it possible to pass my clientId (from my actions project) to dialogflow-fulfillment for it to decode the token (just as actions-on-google does)?

ps: I know there are JWT-decoding libraries and a suggested procedure I could follow to validate and decode the token. But since dialogflow-fulfillment I guess uses actions-on-google internally somehow, I'm just wondering whether there's a much easier way to do it.

No, as far as I know the token verification is done in Dialogflow class in actions-on-google which handles all actions and communication with Dialogflow's API. That is replaced with WebhookClient in Dialogflow Fulfillment library which doesn't do that. You can check out this link for token verification.

TL;DR

const { OAuth2Client } = require('google-auth-library');

const CLIENT_ID = '<your own actions client id>.apps.googleusercontent.com';

const client = new OAuth2Client(CLIENT_ID);

...

// Then, on intent fulfillment method:

    let conv = agent.conv( );  // Get Actions on Google library conversation object

    let payload = await conv.user._verifyProfile(client, CLIENT_ID); // payload.email

Longer story:

Thanks to @RezaNasiri's link to Using a Google API Client Library, I ended up searching where in actions-on-google source code google-auth-library was used.

I found out that google Conversation object has an User object, which includes a _verifyProfile method. It's supposed to be hidden, though, so be careful when using this with a different library version.

So, if using dialogflow-fulfillment webhook client:

const { WebhookClient } = require('dialogflow-fulfillment');

You need to add google-auth-library:

const { OAuth2Client } = require('google-auth-library');

const CLIENT_ID = '<your own client id>.apps.googleusercontent.com';

const client = new OAuth2Client(CLIENT_ID);

Then you can verify and decode the token like this. Here, signInGetData is the fulfillment method for the actions.intent.SIGN_IN intent:

async function signInGetData(agent) {

  let ctx = agent.context.get('actions_intent_sign_in');

  let signin = ctx.parameters.SIGN_IN;

  let conv = agent.conv( );  // Get Actions on Google library conversation object



  if (signin.status === 'OK') {

    // let idToken = conv.user.profile.token; // here's the token, but we don't need it

    let payload = await conv.user._verifyProfile(client, CLIENT_ID); // <<-- HERE

    if ( payload.email ) {

      conv.ask(`Got your email: ${payload.email}`);

    } else {

      conv.ask(`Got profile but not authorized to get your email...`)

    }

  } else {

    conv.ask(`No access to user data. Never mind...`)

  }

  agent.add(conv);

}