/// <summary>
/// Create a <seealso cref="ReplayMerge"/> to manage the merging of a replayed stream and switching to live stream as
/// appropriate.
/// </summary>
/// <param name="subscription"> to use for the replay and live stream. Must be a multi-destination subscription. </param>
/// <param name="archive"> to use for the replay. </param>
/// <param name="replayChannel"> to use for the replay. </param>
/// <param name="replayDestination"> to send the replay to and the destination added by the <seealso cref="Subscription"/>. </param>
/// <param name="liveDestination"> for the live stream and the destination added by the <seealso cref="Subscription"/>. </param>
/// <param name="recordingId"> for the replay. </param>
/// <param name="startPosition"> for the replay. </param>
public ReplayMerge(Subscription subscription, AeronArchive archive, string replayChannel,
string replayDestination, string liveDestination, long recordingId, long startPosition)
{
var subscriptionChannelUri = ChannelUri.Parse(subscription.Channel);
if (!Context.MDC_CONTROL_MODE_MANUAL.Equals(subscriptionChannelUri.Get(Context.MDC_CONTROL_MODE_PARAM_NAME))
)
{
throw new ArgumentException("Subscription channel must be manual control mode: mode=" +
subscriptionChannelUri.Get(Context.MDC_CONTROL_MODE_PARAM_NAME)
);
}
this.archive = archive;
this.subscription = subscription;
this.replayDestination = replayDestination;
this.replayChannel = replayChannel;
this.liveDestination = liveDestination;
this.recordingId = recordingId;
this.startPosition = startPosition;
this.liveAddThreshold = LIVE_ADD_THRESHOLD;
this.replayRemoveThreshold = REPLAY_REMOVE_THRESHOLD;
subscription.AddDestination(replayDestination);
}
private int AwaitUpdatedRecordingPosition()
{
int workCount = 0;
if (NULL_VALUE == activeCorrelationId)
{
long correlationId = archive.Ctx().AeronClient().NextCorrelationId();
if (archive.Proxy().GetRecordingPosition(recordingId, correlationId, archive.ControlSessionId()))
{
activeCorrelationId = correlationId;
workCount += 1;
}
}
else if (PollForResponse(archive, activeCorrelationId))
{
nextTargetPosition = PolledRelevantId(archive);
if (AeronArchive.NULL_POSITION == nextTargetPosition)
{
long correlationId = archive.Ctx().AeronClient().NextCorrelationId();
if (archive.Proxy()
.GetRecordingPosition(recordingId, correlationId, archive.ControlSessionId()))
{
activeCorrelationId = correlationId;
}
}
else
{
State nextState = State.AWAIT_CATCH_UP;
if (null != image)
{
long position = image.Position;
if (ShouldAddLiveDestination(position))
{
subscription.AddDestination(liveDestination);
isLiveAdded = true;
}
else if (ShouldStopAndRemoveReplay(position))
{
nextState = State.AWAIT_STOP_REPLAY;
}
}
activeCorrelationId = NULL_VALUE;
SetState(nextState);
}
workCount += 1;
}
return(workCount);
}
