Auth0 & Dialogflow Authentication

Question

I would like to use Auth0 to gain access for Google APIs. Was trying to follow the instructions on this post

Currently to trigger Auth0, I used conv.ask(new SignIn()); and app.intent("actions_intent_SIGN_IN", (conv, params, signin) => { ... })

I get a token from const code = conv.user.access.token; in my actions_intent_SIGN_IN.

However, it seems that this token isn't the token that is used to gain an access_token for Google, aka thru POST /oauth/token. Whatever this token is, it seems like it doesn't work for any of the requests except GET /userinfo. On Google Cloud Functions, I get this on my log:

{ error: 'invalid_grant', error_description: 'Invalid authorization code' }

I played around for a bit with Postman and managed to retrieve the (seemingly?) correct authorization code that can be used for POST /oauth/token thru GET /authorize and building my own url like https://[APP NAME].auth0.com/authorize?response_type=code&client_id=[CLIENT ID]&redirect_uri=[REDIRECT URI]. The authorization code appeared in https://[APP NAME].auth0.com/login/callback?code=[CODE HERE]

The issue is - how do I retrieve the code=[CODE HERE] from dialogflow?

Answer 1

You can authenticate with service accounts that use OAuth2.0 -- you can read more about that in general here and they'll save you a network call. You'll also need to find the appropriate Google API scope(s) here . Dialogflow has samples that show how this is done on Github, for example .

const {google} = require('googleapis');
const serviceAccount =  { };   // Enter Service Account private key JSON

const client = new google.auth.JWT({
  email: serviceAccount.client_email,
  key: serviceAccount.private_key,
  scopes: ['https://www.googleapis.com/auth/spreadsheets', 'https://www.googleapis.com/auth/drive']
});