Cats Effect 2 executor doesn't shift back to the compute pool

[pjurczenko]

The current implementation of Cats Effect 2 executor relies solely on Async.async method, which doesn't shift the execution back to the compute pool. This means that operations subsequent to the ElasticSearch queries will be performed on the dispatcher threads used for the non-blocking I/O, which is definitely undesirable. This is how the executor could look like to prevent this:

import cats.syntax.apply._

class CatsEffectExecutor[F[_]: Async: ContextShift] extends Executor[F] {
  override def exec(client: HttpClient, request: ElasticRequest): F[HttpResponse] =
    Async[F].async(cb => client.send(request, cb)) <* ContextShift[F].shift
}

However, such a change would be breaking the binary compatibility.

@sksamuel how do you approach such breaking changes in the elastic4s releases?

[sksamuel]

We can do this for the 8.0 release which will contain other breaking changes.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-sebastien-boulet]

This is still relevant