My application has a login page that contains only a button that redirects to the WSO2 Identity Server Authorization Server.
This redirect is done by the library angular-oauth2-oidc.
Then I have a backend that calls WSO2 SCIM2.O api's.
In my OAuthConfig i specify only the clientId (because i know that the client secret should never be in the front-end) and I've noticied that the library automatically uses the Authorization code with PKCE because in the url it add the parameter code_challenge, and I'm fine with it since i read that this type of flow is good when you don't want to use the client secret.
When I insert my credentials, I'm redirect to the url that I specified in the redirect_uri of the OAuthConfig, then i click on a button to add a new item and this event calls my backend api (which calls the wso2 scim api). And it doesn't work.
But if i specify in the OAuthConfig the clientID AND the clientSecret, then it works.
And i don't understand why since I'm using the flow with PKCE. I'm guessing that the problem is with the access token that gets generated? Is there any step I'm missing?