SecurityContextRequestPostProcessorSupport small-improvements

[ch4mpy]

1. SecurityContextRequestPostProcessorSupport does not define abstract method. There is no need for it to be abstract
2. SecurityContextRequestPostProcessorSupport is stateless. There is no need for it to be a parent class, it can be a collaborator or an interface instead
3. both SecurityContextRequestPostProcessorSupport and TestSecurityContextRepository could be of great use to framework users wishing to extend testing features.

I'm asking to change SecurityContextRequestPostProcessorSupport an TestSecurityContextRepository visibility to public.

I also propose to modify existing request post-processors so that it use SecurityContextRequestPostProcessorSupport as collaborator instead of extending it.

[rwinch]

Thank you for reaching out @ch4mpy Can you describe what you are trying to achieve that is not simple at this time?

[ch4mpy]

@rwinch I can't contribute test MockMVC request post-processor extending something else (breaks existing patterns as all other security related RequestPostProcessors extend SecurityContextRequestPostProcessorSupport).

Use case at the very bottom of https://github.com/ch4mpy/spring-security/blob/gh-6634--jwt-reactive-flow/test/src/main/java/org/springframework/security/test/web/servlet/request/SecurityMockMvcRequestPostProcessors.java, JwtRequestPostProcessor definition

[ch4mpy]

@rwinch, I won't be able any longer to execute changes you would request. When opening this ticket, I thought a week would have been enough to solve it. I now have to go at sea, with almost no Internet connection for the coming two month, sorry. I hope I managed to give modification rights to Spring team.

Please note there are two commits on this branch:

• first removes all dependencies from request post-processors to SecurityContextRequestPostProcessorSupport as parent and add it as collaborator on the only few requiring it
• second holds visibility modifications and moves of newly public classes to their own files

[rwinch]

I'm closing this as invalid because user's can easily delegate to the existing public APIs to achieve the same things. For example:

@Override
public MockHttpServletRequest postProcessRequest(MockHttpServletRequest request) {
	Authentication authentication = ...;
	return SecurityMockMvcRequestPostProcessors.authentication(token).postProcessRequest(request);
}