Consider adding methods to get HttpHeaders as MultiValueMap

[ZIRAKrezovic]

Related:

#33913

The change may break implementations expecting HttpHeaders to be an instance of MultiValueMap.

Would it be possible to add a method that provides (readonly) MultiValueMap from HttpHeaders, such as an instance method

public MultiValueMap<String, String> asMultiValueMap();

A helper/util method is also welcome.

Thanks

[bclozel]

We should have fallbacks already in place, see https://github.com/spring-projects/spring-framework/wiki/Spring-Framework-7.0-Release-Notes#httpheaders-changes

If it doesn't work out for you, please elaborate.

[ZIRAKrezovic]

Alright, I have seen the fallbacks with @Deprecated(forRemoval = true) which was not feasible if we do not want to add dependency to spring-web but want to be able to handle HttpHeaders.

However, there's a non-deprecated result which returns Map<String, String> and that should be sufficient. I hope it won't get deprecated as well.

Thanks for the feedback, you may close the task.

[bclozel]

Alright, I have seen the fallbacks with @deprecated(forRemoval = true) which was not feasible if we do not want to add dependency to spring-web but want to be able to handle HttpHeaders.

The method has been introduced as deprecated directly, because we want developers to notice the Javadoc there: it explains the known limitations of the MultiValueMap approach. This is why we changed HttpHeaders in the first place. You can keep using this method but be aware of the limitations and that there is a performance cost.

Cheers!