Reactor-netty: Investigate if HttpServer can avoid producing cancel on single mono responses

[smaldini]

We have a reporter in webflux (https://github.com/spring-projects/spring-framework/issues/22952) observing an unnecessary cancel signal for single mono responses.
After initial investigation it appears that both webflux and netty can produce this undesired cancel. In the case of reactor-netty it appears that we will callback cancel after successful single response write in HttpTrafficHandler.

[duke-cliff]

When will be the release date of 0.9.0? Before this fix, we have to downgrade to 0.8.6.

[Delorien84]

Hi,
I do not agree marking this issue as enhancement. From my point of view it is a bug, as it broke all org.springframework.web.server.WebFilter those using onComplete callback.

[alfred-thomas]

I agree with @Delorien84 - For us it means we cannot upgrade from Spring Boot 2.1.4 until this has been fixed, unless we start using Undertow instead of Netty

[winster]

Do you think, https://github.com/reactor/reactor-addons/issues/236 is related. It is still open there.

[violetagg]

@winster What do you mean? This issue is fixed.
If you think it is not, create a new issue with reproducible example.

[winster]

Yes, the issue in reactor-netty is fixed. But there are other components in reactor where it is still open.
reactor-extra - https://github.com/reactor/reactor-addons/issues/236
reactor-core - https://github.com/reactor/reactor-core/issues/2396

I commented here to know in case are these issues related.