public void TrySet_should_return_true_if_value_changed()
{
boolean.Value = true;
boolean.TrySet(true).Should().BeFalse();
boolean.TrySet(false).Should().BeTrue();
boolean.TrySet(false).Should().BeFalse();
}
/// <summary>
/// Makes sure retrieving items that were postponed,
/// because they would exceed <see cref="DataflowBlockOptions.BoundedCapacity"/>,
/// is currently running.
/// </summary>
void EnsurePostponedProcessing()
{
if (postponedProcessing.TrySet())
{
Task.Factory.StartNew(RetrievePostponed, options.CancellationToken,
TaskCreationOptions.PreferFairness, options.TaskScheduler);
}
}
/// <summary>
/// Starts non-greedy creation of tuples, if one doesn't already run.
/// </summary>
void EnsureNonGreedyProcessing()
{
if (nonGreedyProcessing.TrySet())
{
Task.Factory.StartNew(NonGreedyProcess,
dataflowBlockOptions.CancellationToken,
TaskCreationOptions.PreferFairness,
dataflowBlockOptions.TaskScheduler);
}
}
/// <summary>
/// Starts non-greedy creation of batches, if one doesn't already run.
/// </summary>
/// <param name="manuallyTriggered">Whether the batch was triggered by <see cref="TriggerBatch"/>.</param>
void EnsureNonGreedyProcessing(bool manuallyTriggered)
{
if (nonGreedyProcessing.TrySet())
{
Task.Factory.StartNew(() => NonGreedyProcess(manuallyTriggered),
dataflowBlockOptions.CancellationToken,
TaskCreationOptions.PreferFairness,
dataflowBlockOptions.TaskScheduler);
}
}
internal void ContinueWithCore(Task continuation, TaskContinuationOptions kind,
TaskScheduler scheduler, Func <bool> predicate)
{
// Already set the scheduler so that user can call Wait and that sort of stuff
continuation.taskScheduler = scheduler;
continuation.scheduler = ProxifyScheduler(scheduler);
continuation.schedWait.Set();
AtomicBoolean launched = new AtomicBoolean();
EventHandler action = delegate(object sender, EventArgs e) {
if (!launched.Value && launched.TrySet())
{
if (!predicate())
{
return;
}
if (!ContinuationStatusCheck(kind))
{
continuation.CancelReal();
continuation.Dispose();
return;
}
CheckAndSchedule(continuation, kind, scheduler, sender == null);
}
};
if (IsCompleted)
{
action(null, EventArgs.Empty);
return;
}
completed.Enqueue(action);
// Retry in case completion was achieved but event adding was too late
if (IsCompleted)
{
action(null, EventArgs.Empty);
}
}
private async Task EnsureNodeExistsAsync()
{
if (!await EnvironmentExistsAsync().ConfigureAwait(false))
{
return;
}
var existsNode = await zooKeeperClient.ExistsAsync(new ExistsRequest(replicaNodePath) { Watcher = nodeWatcher }).ConfigureAwait(false);
if (!existsNode.IsSuccessful)
{
return;
}
if (registrationAllowed.TrySet(settings.RegistrationAllowedProvider?.Invoke() ?? true))
{
log.Info(registrationAllowed ? "Registration has been allowed." : "Registration has been denied.");
}
if (!registrationAllowed)
{
if (existsNode.Stat != null)
{
await DeleteNodeAsync().ConfigureAwait(false);
}
return;
}
if (existsNode.Stat != null)
{
if (existsNode.Stat.EphemeralOwner == zooKeeperClient.SessionId)
{
nodeCreatedOnceSignal.Set();
return;
}
var lastConnected = new DateTime(Interlocked.Read(ref lastConnectedTimestamp), DateTimeKind.Utc);
var nodeCreationTime = existsNode.Stat.CreatedTime;
if (nodeCreationTime > lastConnected)
{
log.Warn(
"Node with path '{ReplicaNodePath}' already exists " +
"and has owner session id = {NodeEphemeralOwner:x16}, " +
"which differs from our id = {ClientSessionId:x16}. " +
"But it was created recently (at {NodeCreationTime}) so we won't touch it. " +
"This may indicate several beacons with same environment, application and replica exist.",
replicaNodePath,
existsNode.Stat.EphemeralOwner,
zooKeeperClient.SessionId,
nodeCreationTime);
return;
}
log.Warn(
"Node with path '{ReplicaNodePath}' already exists, " +
"but looks like a stale one from ourselves. " +
"It has owner session id = {NodeEphemeralOwner:x16}, " +
"which differs from our id = {ClientSessionId:x16}. " +
"It was created at {NodeCreationTime}. " +
"Will delete it and create a new one.",
replicaNodePath,
existsNode.Stat.EphemeralOwner,
zooKeeperClient.SessionId,
nodeCreationTime);
if (!await DeleteNodeAsync().ConfigureAwait(false))
{
return;
}
}
var createRequest = new CreateRequest(replicaNodePath, CreateMode.Ephemeral)
{
Data = replicaNodeData
};
var create = await zooKeeperClient.CreateAsync(createRequest).ConfigureAwait(false);
if (create.IsSuccessful)
{
nodeCreatedOnceSignal.Set();
}
if (!create.IsSuccessful && create.Status != ZooKeeperStatus.NodeAlreadyExists)
{
log.Error("Node creation has failed.");
return;
}
await zooKeeperClient.ExistsAsync(new ExistsRequest(replicaNodePath) { Watcher = nodeWatcher }).ConfigureAwait(false);
}