The @Relation annotation should be respected if evaluating the 'class' property of a Siren entity

[marcuslange]

Describe the bug
@relation annotation is not reflected in response.

To Reproduce
Add @relation to a RepresentationModel and request object.

Expected behavior
@relation(itemRelation = "Person") should produce "class": ["Person"]

Environment:

• Spring HATEOAS Siren version 1.2.0
• Spring Boot version 2.5.2
• Spring Framework version 5.3.8

[ingogriebsch]

Hey @marcuslange this is in my opinion not a bug. As the reference documentation mentions here, the library implements a really simple approach at the moment to evaluate the class property of a Siren entity (means, evaluating the @Relation annotation is not supported through the implementation).

Additionally it is not yet clear to me if the @Relation annotation should in general be used as a basis to evaluate the class property of a Siren entity.

We will think about how to support this use case. In the meantime you are able to provide a custom implementation of the SirenEntityClassProvider SPI as a @Bean to let the library pick up and use it.

It looks like Spring HATEOAS AnnotationLinkRelationProvider or Spring Core AnnotatedElementUtils are your friends if you want to implement a fast and easy first solution. :)