Timer API does not support Kotlin suspend function (coroutines)

[AleksanderBrzozowski]

Please describe the feature request.

For standard (non suspend functions) it is possible to use record function to measure method invocation time:

Timer.builder("method.timed")
            .register(meterRegistry)
            .record { fn() } // fn() is a standard, non suspend function

However, it is not possible to call a suspend function from within record block:

Timer.builder("method.timed")
            .register(meterRegistry)
            .record { suspendFn() } // Suspension functions can be called only within coroutine body

The support for suspend functions should be added to the library.

Rationale
Suspend functions are popular for non-blocking API, and it is currently not possible to measure time needed to call suspend functions without having a custom function to record the time.

Additional context
Maybe this could be added as a extension function to the Timer interface.

[micheljung]

I'd love to see this, too. See also: https://techlab.bol.com/en/blog/measuring-execution-time-in-kotlin-coroutines/

[shakuzen]

We would review a pull request to add this functionality. There is a similar pull request open now for adding an extension function to Observation to support suspend functions - see #4823.