Auth0 between Angular and Drupal

Hello to all of you! Hope you’re all doing good in these difficult times.

I am in the middle of something that currently drives me crazy: I’m supposed to set up a SSO logic between an Angular app and a Drupal backend. What I’m trying to do:

  • login via Auth0 in the Angular app, not in Drupal (no problem with that)
  • check the current connection made in Angular in Drupal, and connect the user in Drupal if it’s valid (the auth0 user id is stored in db to make the correspondance with the Drupal user id)

Subproblem: the Drupal 7 backend (which is not mine) is stuck in PHP5.6, so I’m stuck with the 5.7 version of auth0-php library, and it’s hard to find documentation for it… Auth0 was once set up on that backend, but it was like 4 years ago, and not well done.

I have trouble apprehending the whole logic of what I’m supposed to do on the Drupal side. I defined a callback url to a custom module in Drupal where I get the code sent back by Auth0, but then, whenever I try to verify the code, or get a token, I get errors…

Has anyone of you an idea -even something very basic- of how I’m supposed to do that (even if it’s simple PHP and not Drupal logic)? Or is it just an impossible thing to do?

Thanks A LOT in advance!