Improve OAuth2LoginSpec with more configuration options

[hartmut-co-uk]

Summary

Improve org.springframework.security.config.web.server.ServerHttpSecurity.OAuth2LoginSpec
for more configuration options.

Actual Behavior

1. Chaining of OAuth2LoginSpec not available, missing public ServerHttpSecurity and() { return ServerHttpSecurity.this; }
2. Static routes for

   /oauth2/authorization/{registrationId}
/login/oauth2/code/{registrationId}

Expected Behavior

1. allow chaining

2. 1. allow to override/configure oauthRedirectFilter (or authorizationRequestBaseUri in particular)
   2. allow to override/configure AuthenticationWebFilter.requiresAuthenticationMatcher (or PathPatternParserServerWebExchangeMatcher -> pattern => requestBaseUri in particular)

Configuration

http.oauth2Login();

Version

Boot 2.1.0.SNAPSHOT
Spring Security 5.1.0.M2

[rwinch]

The first part was easy so I fixed it in a separate issue. The next pieces are going to need to wait until we get #5610 resolved

[VijaySidhu]

I am writing Service with WebFlux Framework Below are Technologies i am trying to use
Spring Boot 2.1.0.M3
Spring Security 5.1.0.RC2
In Spring Security It's trying to match /oauth2/authorization/{registrationId} with Path i configured which is different and it's not matching and throwing 401.
Is there any way to override /oauth2/authorization/{registrationId} this with value i am using

[nickbr23]

Have the static routes:

/oauth2/authorization/{registrationId}
/login/oauth2/code/{registrationId}

Been made overridable or configurable yet?