In firebase - How to generate an idToken on the server for testing purposes?

Question

I want to test a a cloud function that creates users.

In normal cases, inside the browser i generate an idToken and i send it to server via headers:

Answer 1

From Exchange custom token for an ID and refresh token, you can transform a custom token to an id token with the api. Hence, you just have to generate a custom token first from the uid, then transform it in a custom token. Here is my sample:

const admin = require('firebase-admin');
const config = require('config');
const rp = require('request-promise');

module.exports.getIdToken = async uid => {
  const customToken = await admin.auth().createCustomToken(uid)
  const res = await rp({
    url: `https://www.googleapis.com/identitytoolkit/v3/relyingparty/verifyCustomToken?key=${config.get('firebase.apiKey')}`,
    method: 'POST',
    body: {
      token: customToken,
      returnSecureToken: true
    },
    json: true,
  });
  return res.idToken;
};