Present a different login form/theme depending on the RP that initiated the login request

[mig5]

Hi,

Hydra currently seems to have a single config value/environment variable for the Login application.

My use case requires me to show a slightly different themed login form depending on which RP is in use. My RPs are effectively 'white-labelled' so that the login form matches the theme of the RP itself, but the OP/IDP is the same.

Is there any way I can get the Login app to infer which RP the login request began at - without relying on the HTTP Referer header (which won't be available due to the use of the Referrer-Policy security header, and which I'm not sure would work anyway, since I have a feeling the referrer would be the Hydra public API endpoint itself)?

#1851 says "you can redirect in your login/consent app based on e.g. the client ID or some other parameter." It's not clear to me how to do that - can the URLS_LOGIN include some sort of interpolated query parameter that represents the client ID? As far as I can tell, all that the Login app 'sees' is the login_challenge query parameter, but no information as to what the RP was. Unless that's infer-able from the challenge itself?

[vinckr]

The login_challenge is used by the Login Endpoint to fetch information about the request.
If you look at the "Login Challenge Response" here, you can see that you get information on the client and some more.

Does that help with your use case?

[mig5]

Thank you @vinckr, that is perfect. I didn't realise the Login Challenge response contained such a rich set of data about the oAuth2.0 client - including the redirectUris, client name, etc. Thanks again.