Spring org.springframework.web.reactive.function.client.WebClientRequestException: Unexpected handshake message: certificate

Hello, when trying out the webclient of webflux calling a third-party service, there was an exception with the handshake certificate. Have you ever seen a similar scenario。

org.springframework.web.reactive.function.client.WebClientRequestException: Unexpected handshake message: certificate at org.springframework.web.reactive.function.client.ExchangeFunctions$DefaultExchangeFunction.lambda$wrapException$9(ExchangeFunctions.java:136) ~[spring-webflux-6.0.4.jar!/:6.0.4] Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: Error has been observed at the following site(s): *__checkpoint ⇢ Request to POST https://buy.itunes.apple.com/verifyReceipt [DefaultWebClient] Original Stack Trace: at org.springframework.web.reactive.function.client.ExchangeFunctions$DefaultExchangeFunction.lambda$wrapException$9(ExchangeFunctions.java:136) ~[spring-webflux-6.0.4.jar!/:6.0.4] at reactor.core.publisher.MonoErrorSupplied.subscribe(MonoErrorSupplied.java:55) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.Mono.subscribe(Mono.java:4444) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxOnErrorResume$ResumeSubscriber.onError(FluxOnErrorResume.java:103) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxPeek$PeekSubscriber.onError(FluxPeek.java:222) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxPeek$PeekSubscriber.onError(FluxPeek.java:222) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxPeek$PeekSubscriber.onError(FluxPeek.java:222) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.MonoNext$NextSubscriber.onError(MonoNext.java:93) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.MonoFlatMapMany$FlatMapManyMain.onError(MonoFlatMapMany.java:204) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.SerializedSubscriber.onError(SerializedSubscriber.java:124) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxRetryWhen$RetryWhenMainSubscriber.whenError(FluxRetryWhen.java:225) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxRetryWhen$RetryWhenOtherSubscriber.onError(FluxRetryWhen.java:274) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxContextWrite$ContextWriteSubscriber.onError(FluxContextWrite.java:121) ~[reactor-core-3.5.2.jar!/:3.5.2] at reactor.core.publisher.FluxConcatMapNoPrefetch$FluxConcatMapNoPrefetchSubscriber.maybeOnError(FluxConcatMapNoPrefetch.java:326) ~[reactor-core-3.5.2.jar!/:3.5.2]

Comment From: bclozel

Thanks for getting in touch, but it feels like this is a question that would be better suited to Stack Overflow. As mentioned in the guidelines for contributing, we prefer to use the issue tracker only for bugs and enhancements. Feel free to update this issue with a link to the re-posted question (so that other people can find it) or add some more details if you feel this is a genuine bug.

This is likely to be a certificate or protocol issue, so not related to Spring.