XmlMapper behaviours defined in rest client builder message converters are not considered in serialisation -- spring-boot-starter-parent 3.4.4 and 3.4.5

[MianoKariuki]

I have observed, that since the release of spring-boot-starter-parent version 3.4.4, that the XmlMapper behaviours defined for rest client builder message converter, are not being used in serialisation. PFA, report and sample project on the matter

Bug report.pdf

report-spring-rest-client-issue.zip

[bclozel]

This is due to a Spring Framework bug fix in #34439.
Previously, the XML HTTP converter was not registered automatically for RestClient instances, and it the case as of 6.2.4.

Now this is causing an issue with your application because you were relying on the fact that there was no message converter present for processing XML HTTP messages and that your custom converter (added last) would be used for this. This is not the case anymore as the automatically registered. one takes precedence now.

You can fix your application by removing the default one and replacing it with your custom converter.

var restClient = RestClient.builder()
					.baseUrl("http://localhost:8080/")
					.messageConverters(converters -> {
						converters.removeIf(converter -> converter instanceof MappingJackson2XmlHttpMessageConverter);
						converters.add(new MappingJackson2XmlHttpMessageConverter(mapper));
					})

I'm closing this issue as the change was done in Framework and I don't think we should roll back this change.

Thanks for the report!

[MianoKariuki]

This is due to a Spring Framework bug fix in #34439. Previously, the XML HTTP converter was not registered automatically for RestClient instances, and it the case as of 6.2.4.

Now this is causing an issue with your application because you were relying on the fact that there was no message converter present for processing XML HTTP messages and that your custom converter (added last) would be used for this. This is not the case anymore as the automatically registered. one takes precedence now.

You can fix your application by removing the default one and replacing it with your custom converter.

var restClient = RestClient.builder()
.baseUrl("http://localhost:8080/")
.messageConverters(converters -> {
converters.removeIf(converter -> converter instanceof MappingJackson2XmlHttpMessageConverter);
converters.add(new MappingJackson2XmlHttpMessageConverter(mapper));
})
I'm closing this issue as the change was done in Framework and I don't think we should roll back this change.

Thanks for the report!

Thank you. This has been both insightful and instructful in resolving the encountered issue.