php oauth server - link dump

PHP 5

https://www.sitepoint.com/creating-a-php-oauth-server/

https://bshaffer.github.io/oauth2-server-php-docs/

PHP 7

https://github.com/thephpleague/oauth2-server

Using firebase (PHP 7)

https://github.com/jeromegamez/firebase-php-examples

Edit: We finally did not use any of these, and instead authenticated using google sign-in against our own database as mentioned at https://hnsws.blogspot.com/2021/12/using-google-sign-in-for-our-php-portal.html