Context propagation is broken from Akka 2.8.0 onwards

[nathanmbrown]

We have observed when upgrading to Akka 2.8.x that context propagation is not working. We use it for logging context and also http header propagation but neither of these work.
Everything works fine for Akka 2.7.

[alexmihailov]

I also see this problem. I'm using Lagom 1.6.7, Akka Http 10.1.15, Akka 2.6.18, Play 2.8.11

[hughsimpson]

I'm more interested in getting older versions of Akka (and, by extension, pekko) working with scala 3 right now, but it's certainly something worth fixing. If anyone wants to help out, a pr with appropriate builds just to line up the dependencies for the more recent versions of Akka would save a lot of time, and I'll be happy to use them as a jumping-off point. Otherwise given licensing changes for those versions this is gonna go down the pile a little

[hughsimpson]

Now that scala 3 support is in a better place I might take a swing at this soon

[Forbiddensequence]

I have noticed that problem above appears from kamon version 2.6.3 where #1271 were added. I think main problem is in style of adding configuration, and its order merging in final conf file.

In this style it is important that kamon-executor module config should be merged before all others, because it sets number of applied classes by = operator and overrides previously added values

kanela.modules {
  executor-service {
    within = [
      "scala.concurrent.ExecutionContext\\$",
      "scala.concurrent.ExecutionContext\\$Implicits\\$"
    ]
  }
}

But in others module (kamon-jdbc, kamon-scala-future) config is expanded by other style - by adding values to existing conf

kanela.modules {
  executor-service {
    within += "scala.concurrent.impl.CallbackRunnable"
    within += "scala.concurrent.impl.Future\\$PromiseCompletingRunnable"
    within += "scala.concurrent.impl.Promise\\$Transformation"
  }
}

And that breaks all instrumentation if kamon-scala-future is loaded first.

I suggest to add classes by += operator in previous case, and, in my observation, that will fix problem .