/// <summary>
/// It's recommended to use this method (or another TryAwaitOrTimeout or AwaitOrTimeout method)
/// instead of just Task.WhenAny(taskToAwait, Task.Delay(timeout))
/// because this method cancels the timer for timeout while <c>Task.Delay(timeout)</c>.
/// If the number of “zombie” timer jobs starts becoming significant, performance could suffer.
/// For more detailed explanation see https://devblogs.microsoft.com/pfxteam/crafting-a-task-timeoutafter-method/
/// </summary>
/// <returns><c>true</c> if <c>taskToAwait</c> completed before the timeout, <c>false</c> otherwise</returns>
internal static async Task <bool> TryAwaitOrTimeout(this IAgentTimer agentTimer, Task taskToAwait
, AgentTimeInstant until, CancellationToken cancellationToken = default
)
{
var timeoutDelayCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
var timeoutDelayTask = agentTimer.Delay(until, timeoutDelayCts.Token);
try
{
var completedTask = await Task.WhenAny(taskToAwait, timeoutDelayTask);
if (completedTask == taskToAwait)
{
// await taskToAwait to make it throw if taskToAwait is faulted or cancelled so it will throw as it should
await taskToAwait;
return(true);
}
Assertion.IfEnabled?.That(completedTask == timeoutDelayTask
, $"{nameof(completedTask)}: {completedTask}, {nameof(timeoutDelayTask)}: timeOutTask, {nameof(taskToAwait)}: taskToAwait");
// await timeout task in case it is cancelled and did not timed out so it will throw as it should
await timeoutDelayTask;
return(false);
}
finally
{
if (!timeoutDelayTask.IsCompleted)
{
timeoutDelayCts.Cancel();
}
timeoutDelayCts.Dispose();
}
}
private static void VerifyInstantsAreCompatible(AgentTimeInstant i1, AgentTimeInstant i2, [CallerMemberName] string caller = null)
{
if (i1.IsCompatibleWith(i2._sourceAgentTimer))
{
return;
}
var opName = caller == null ? "an operation" : $"operation {caller}";
throw new InvalidOperationException($"It's illegal to perform {opName} on two AgentTimeInstant instances " +
"that did not originate from the same timer." +
$" The first AgentTimeInstant: timer: {i1._sourceAgentTimer}, value: {i1._elapsedSinceTimerStarted}." +
$" The second AgentTimeInstant: timer: {i2._sourceAgentTimer}, value: {i2._elapsedSinceTimerStarted}.");
}
public bool Equals(AgentTimeInstant other) => _sourceAgentTimer == other._sourceAgentTimer && _elapsedSinceTimerStarted == other._elapsedSinceTimerStarted;
/// <summary>
/// It's recommended to use this method (or another TryAwaitOrTimeout or AwaitOrTimeout method)
/// instead of just Task.WhenAny(taskToAwait, Task.Delay(timeout))
/// because this method cancels the timer for timeout while <c>Task.Delay(timeout)</c>.
/// If the number of “zombie” timer jobs starts becoming significant, performance could suffer.
/// For more detailed explanation see https://devblogs.microsoft.com/pfxteam/crafting-a-task-timeoutafter-method/
/// </summary>
/// <returns>
/// (<c>true</c>, result of <c>taskToAwait</c>) if <c>taskToAwait</c> completed before the timeout, <c>false</c>
/// otherwise
/// </returns>
internal static async Task <ValueTuple <bool, TResult> > TryAwaitOrTimeout <TResult>(this IAgentTimer agentTimer, Task <TResult> taskToAwait
, AgentTimeInstant until, CancellationToken cancellationToken = default
)
{
var hasTaskToAwaitCompletedBeforeTimeout =
await TryAwaitOrTimeout(agentTimer, (Task)taskToAwait, until, cancellationToken);
return(hasTaskToAwaitCompletedBeforeTimeout, hasTaskToAwaitCompletedBeforeTimeout ? await taskToAwait : default);
