How to get the first response of calling 5 requests with Http call? The use case is sending 5 http requests then get the first response and cancel others. Any suggestions?

Use select function. Register all deferred in it and after first receive cancel others.

That's really helpful. Thank you so much.

@Jan Skrasek: Would you mind sharing a snippet of what that would look like? (For learning purposes.) I'm assuming you're referring to "Selecting deferred values", but am not familiar with the

select { }

function. Perhaps something like:

// Ugly code
val requests = List<Deferred<String>>(5) {
    delay(Random.nextInt(0, 1000).toLong())
    async { "Response #$it" }
}
val response = select<String> {
    requests.withIndex().forEach { (index, deferred) ->
        deferred.onAwait { answer ->
            requests.forEach { it.cancel() }
            "Deferred $index produced answer '$answer'"
        }
    }
}

Alternative with

Flow

withTimeout(limit) {
 merge(::func1.asFlow(),::func2.asFlow(),... ). first()

} (formatting not working on phone)

@Richard Gomez your's example seems reasonable, what's not working? You may take a look at some official samples: https://github.com/Kotlin/kotlinx.coroutines/blob/master/kotlinx-coroutines-core/jvm/test/guide/example-select-04.kt

your's example seems reasonable, what's not working?

Nothing in particular, just confirming that I have the right idea. 🙂 Is there a more idiomatic way to cancel a list of jobs than

requests.forEach(Job::cancel)

? I suppose you could run them in an ad-hoc context and cancel that once the first is completed.