RemoveJsonAttributesResponseBody filter does not exists in WebMVC context : remove it from documentation or implement it

[lassellea-sfeir]

Describe the bug
Hi,
when we read Spring Gateway documentation, we can think that RemoveJsonAttributesResponseBody can be used in WebMVC context :

• https://docs.spring.io/spring-cloud-gateway/reference/spring-cloud-gateway-server-webmvc/filters/removejsonattributesresponsebody.html
• https://github.com/spring-cloud/spring-cloud-gateway/blob/main/docs/modules/ROOT/pages/spring-cloud-gateway-server-webmvc/filters/removejsonattributesresponsebody.adoc#removejsonattributesresponsebody-filter

But in fact, this filter does not exist in WebMVC context :

Caused by: java.lang.IllegalArgumentException: Unable to find operation interface org.springframework.web.servlet.function.HandlerFilterFunction for removeJsonAttributesResponseBody with args {_genkey_0=myjsonattribute}

No RemoveJsonAttributesResponseBody class found in sources : https://github.com/spring-cloud/spring-cloud-gateway/tree/main/spring-cloud-gateway-server-webmvc/src/main/java/org/springframework/cloud/gateway/server/mvc/filter

-> Please update documentation or implement this filter : it is very important, because we are doing design based on documentation

[adityaanikam]

Confirmed both halves: the adoc page for RemoveJsonAttributesResponseBody is there under the webmvc docs, and none of the 32 filter classes under server/mvc/filter implement it, so the IllegalArgumentException is expected given the current state, not a config mistake on your end.

The two fixes you named aren't equally sized though. Deleting the doc page is trivial. Porting the filter from WebFlux means writing real logic to remove JSON body attributes for the synchronous WebMVC filter chain, which is an actual feature, not a doc fix. Given that gap I'd rather know which direction is wanted before touching anything, is this meant to be implemented for webmvc at some point, or was the doc just written ahead of the code?

[lassellea-sfeir]

With this PR this good : kalayciburak@60a8037