Traces are not propagated from Spring WebFlux WebFilter into a suspend handler function (Kotlin)

[igor-baltiyskiy-tempo]

When a Controller with suspend handler function is used, and there's a WebFilter that uses mono {} builder function from Kotlin, then traces from WebFilter are not propagated to the handler function.

See attached sample project.

dd-trace-bug-repro.zip

[rajki]

+1, also facing the same issue.

[dyoma]

We did more research and it turned out that with the following options the sample server works as expected. Here we disable all integrations and enable only Kotlin coroutines, Reactor and Netty:

-Ddd.trace.integration.opentracing.enabled=true
-Ddd.integrations.enabled=false
-Ddd.trace.integration.kotlin_coroutine.experimental.enabled=true
-Ddd.trace.integration.reactor-core.enabled=true
-Ddd.trace.integration.reactor-hooks.enabled=true
-Ddd.trace.integration.netty.enabled=true

BTW, the documentation misses the reactor-hooks option for Project Reactor