/// <summary>
/// Replay all events since the last snapshot.
/// </summary>
/// <returns>
/// A <see cref="Task"/> representing the work performed.
/// </returns>
public async Task ReplayUnappliedEvents()
{
if (!this.IsBeingReplayed)
{
try
{
this.IsBeingReplayed = true;
var currentEventId = this.LastJournaledEventId;
await this.journal.ReadFrom(currentEventId).ForEachAsync(
async @event =>
{
// Update internal state.
if (@event.EventId > this.LastJournaledEventId)
{
this.LastJournaledEventId = @event.EventId;
}
// Deserialize the event.
var request = SerializationManager.DeserializeFromByteArray <MethodInvocation>(@event.Event);
// Apply the event.
await GrainExecutionHelper.ApplyRequest(this.grain, request);
});
}
finally
{
this.IsBeingReplayed = false;
}
}
}
/// <summary>
/// Journal the current request.
/// </summary>
/// <returns>
/// The <see cref="Task"/>.
/// </returns>
public async Task WriteJournal()
{
if (!this.IsBeingReplayed)
{
if (++this.journaledSinceLastSnapshot % this.journalWritesBetweenSnapshots == 0)
{
await this.WriteSnapshot();
}
var currentRequest = GrainExecutionHelper.CurrentRequest(this.grain);
if (currentRequest != null)
{
var bytes = SerializationManager.SerializeToByteArray(currentRequest);
var nextEventId = this.LastJournaledEventId + 1;
await this.journal.Append(bytes, nextEventId);
this.LastJournaledEventId = nextEventId;
}
}
}
