Investigate if HttpServer can avoid producing cancel on single mono responses

[smaldini]

We have a reporter in webflux (spring-projects/spring-framework#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