Is there a way to run suspending code in blocking mode reliably?

runBlocking

seems to give up immediately it encounters an interrupt, leaving the suspending function in a possibly corrupt mode. Or maybe I'm only overthinking this? 🤔

What do you mean? Can you provide an example?

Hi @elizarov. I have a setup like:

suspend fun doStuff() {
  // Call suspending API method
  someDb.use {
    // write stuff to db
  }
}

Now, I need to run this function in blocking mode. Currently, I'm simply doing:

fun blockingFun() = runBlocking {
  doStuff()
}

...but there is a time frame after which the thread could be interrupted. Is there a way to guarantee

doStuff

runs to completion before

runBlocking

throws interrupted exception? PS: I was on mobile and didn't get a notification, would have responded to this earlier

One solution is to do this:

fun blockingFun() = runBlocking {
    run (NonCancellable) { doStuff() }
}

What it does is that

runBlocking

will throw

InterrupedException

if interrupted, but it will not cancel the execution of

doStuff

— it will continue to work even after the

runBlocking

returns with exception (it will execute as if working with

Unconfined

dispatcher)

Yes. I thought about using

run(NonCancellable)

, but I am using some resources that might get closed once

runBlocking

returns I am currently using a

runSilentBlocking

which basically wraps run blocking in a try/catch, but yes, I'll look into tweaking

runBlocking

to make it run uninterruptibly

You are welcome to submit a pull request for kotlinx.coroutines project or, at least, create an issue (in its github tracker)