Wiring in image ownership

Spring WebFlux's ServerWebExchange comes prepared for security by providing a getPrincipal() API that returns Mono<Principal>. While the default version, straight out of Spring Framework, supplies Mono.empty(), Spring Security automatically hooks in a filter to supply a real value via WebSessionSecurityContextRepository.

With Spring Security and Spring Session hooked into all our web calls, we can leverage this information every time a new image is uploaded.

First of all, we can adjust our Image domain object as follows:

    @Data 
    @AllArgsConstructor 
    public class Image { 
 
      @Id private String id; 
      private String name; 
      private String owner; 
    } 

This last code is the same POJO that we've used throughout this book with one change:

• It now has a String owner property. This lets us associate an image with whoever...