References
- https://github.com/thephpleague/oauth2-server - This project was influenced by the PHP League OAuth2 Server and shares a lot of the same ideas.
- https://tools.ietf.org/html/rfc6749#section-4.4
- https://www.oauth.com/oauth2-servers/access-tokens/client-credentials/
- https://www.oauth.com/oauth2-servers/access-tokens/access-token-response/
- https://tools.ietf.org/html/rfc6749#section-4.1
- https://tools.ietf.org/html/rfc7009
- https://tools.ietf.org/html/rfc7636
- https://tools.ietf.org/html/rfc7662
- https://www.oauth.com/oauth2-servers/pkce/
- https://www.oauth.com/oauth2-servers/pkce/authorization-request/