trace information missing in map or flatMap operation after a webclient call about wingtips HOT 1 CLOSED

Hey @bijukunjummen , sorry for the very late response on this.

It's become increasingly clear that we cannot rely on WebClient threading behaviors being consistent, especially between versions of Spring - even supposedly non-breaking version updates of Spring. You can see I just had to drop support for some of the minimal auto-magic tracing propagation wingtips was already attempting to do, due to a breaking change with how spring handles their threading: see this comment in the javadocs.

☝️ is important for your example as well, given that your example does not use webClient.attribute(TracingState.class.getName(), TracingState.getCurrentThreadTracingState()) to propagate the tracing state. Please read the linked javadoc comment carefully, and start using the webClient.attribute(...) mechanism to do the initial tracing state propagation, otherwise you'll upgrade spring someday and all your WebClient calls will fail to do distributed tracing correctly!

There may be some very complex way to auto-magic the tracing state onto threads as WebClient hops from thread to thread, but the effort required would undoubtedly be very large and I'd be skeptical about its fragility.

My recommendation on your specific question around map and flatMap would be to use the wingtips-java8 features (see examples here) to wrap your map and flatMap functions to ensure the proper tracing state is attached when those functions execute. Same idea as what we're dong here in the SB2 webflux sample app.

from wingtips.