another questions about MDC and coroutineContext.....

# coroutines

[Nikky]

another questions about MDC and coroutineContext..

can i update a ThreadContextElement from inside the coroutine ?

issue is this code seems natural

suspend fun doStuff() = withContext(MDCContext() + exceptionHandler()) {
   MDC.put("flow", "do-stuff")
   <http://logger.info|logger.info> { "doing stuff" } // mdc is fine here

   someSuspendFun()

   <http://logger.info|logger.info> { "done doing stuff" } // mdc was reset to the state of MDCContext ie. is empty
}

ideally what i would like to be able to do is update the MDCContext or update the val contextMap: MDCContextMap
after i modify the MDC
( i tried, it fails in different ways )

or use a mechanism where the MDC is stored before doing a suspend call, so any changes are actually picked up

TL;DR currently it leads to rather unnatural looking code and additional nesting or errors that are really hard to find

[gildor]

You cannot use put, it will be rested after suspend

[gildor]

It mentioned in doc

[bezrukov]

Take the current MDCcontext, mutate and modify it, and wrap your suspend fun with one more withContext

[Nikky]

exactly that extra withContext is what i was hoping to avoid, making code really a lot more annoying to write and read

[gildor]

Maybe create an extension function for it?