How to make relative redirect to Authorization Endpoint in Spring OAuth?

Question

I configured a service with oauth2Login.

User is redirected to Authorization Endpoint - /oauth2/authorization/{registrationId} when he/she is not authorized.

I would like to customize redirection in a way that it takes into account path prefix, since application is accessible trough prefix /api/myapp/.

From the source code I can see that there is OAuth2AuthorizationRequestRedirectWebFilter during Spring Security setup and this filter is using DefaultServerRedirectStrategy which decides if location is relative or not. Moreover it uses a contextPath which is hard to set when using Spring Boot.

Unfortunately I don't know how to override default behavior to make redirect relative.

Answer 1

I don't need to modify contextPath. Instead I've registered ForwardedHeaderTransformer as a bean.

This transformer is able to retrieve headers set by proxy (X-Forwarded-Prefix) and sets context path for request correctly.