nim-raft/raft/async_util.nim

47 lines
1.7 KiB
Nim

# nim-raft
# Copyright (c) 2023 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
# * MIT license ([LICENSE-MIT](LICENSE-MIT))
# at your option.
# This file may not be copied, modified, or distributed except according to
# those terms.
import asyncdispatch
import std/times
template awaitWithTimeout[T](operation: Future[T],
deadline: Future[void],
onTimeout: untyped): T =
let f = operation
await f or deadline
if not f.finished:
# If we don't wait for for the cancellation here, it's possible that
# the "next" operation will run concurrently to this one, messing up
# the order of operations (since await/async is not fair)
await cancelAndWait(f)
onTimeout
else:
f.read
template awaitWithTimeout[T](operation: Future[T],
timeout: Duration,
onTimeout: untyped): T =
awaitWithTimeout(operation, sleepAsync(timeout), onTimeout)
template awaitWithTimeout(operation: Future[void],
deadline: Future[void],
onTimeout: untyped) =
let f = operation
await f or deadline
if not f.finished:
# If we don't wait for for the cancellation here, it's possible that
# the "next" operation will run concurrently to this one, messing up
# the order of operations (since await/async is not fair)
await cancelAndWait(f)
onTimeout
template awaitWithTimeout(operation: Future[void],
timeout: Duration,
onTimeout: untyped) =
awaitWithTimeout(operation, sleepAsync(timeout), onTimeout)