Would buffered flows be the current best way of fa...

# coroutines

[Mark Allanson]

Would buffered flows be the current best way of fanning out a number of (comparatively) long running http requests and aggregating the results?

[Casey Brooks]

How would a buffered flow do that?

I woulnd’t use a flow at all. Just launch them all with async, and await all those after they’ve all been launched:

val responses = listOf<Request>()
    .map { async { it.exec() } } // launch each HTTP request in parallel
    .map { it.await() } // wait for the responses to come in

[Mark Allanson]

Yeah I just realised it wouldn';t it would just buffer slow collectors

[Casey Brooks]

Alternatively, pushing the requests into a Channel and setting up “worker” coroutines to pull from that channel with a select expression can give you more control over the level of parallelism you want. Probably would want to push the results into another channel to aggregate them all https://kotlinlang.org/docs/select-expression.html

[Mark Allanson]

Channels would provide better support for cancellation if I wanted to do a "fail fast" type scenario where I wanted to cancel everything if one failed