public async Task <long> Start(ProjectionDaemon daemon)
{
_logger.LogInformation("Starting projection agent for '{ShardName}'", _projectionShard.Name);
var singleFile = new ExecutionDataflowBlockOptions
{
EnsureOrdered = true,
MaxDegreeOfParallelism = 1,
CancellationToken = _cancellation,
};
_commandBlock = new ActionBlock <Command>(processCommand, singleFile);
_loader = new TransformBlock <EventRange, EventRange>(loadEvents, singleFile);
_tracker = daemon.Tracker;
_daemon = daemon;
_fetcher = new EventFetcher(_store, _projectionShard.EventFilters);
_hopper = _projectionShard.Start(this, _logger, _cancellation);
_loader.LinkTo(_hopper, e => e.Events.Any());
var lastCommitted = await _store.Advanced.ProjectionProgressFor(_projectionShard.Name, _cancellation);
_commandBlock.Post(Command.Started(_tracker.HighWaterMark, lastCommitted));
_subscription = _tracker.Subscribe(this);
_logger.LogInformation("Projection agent for '{ShardName}' has started from sequence {LastCommitted} and a high water mark of {HighWaterMark}", _projectionShard.Name, lastCommitted, _tracker.HighWaterMark);
Status = AgentStatus.Running;
Position = lastCommitted;
return(lastCommitted);
}
public async Task <long> Start(ShardStateTracker tracker)
{
_logger.LogInformation($"Starting projection agent for '{_projectionShard.ProjectionOrShardName}'");
_tracker = tracker;
_fetcher = new EventFetcher(_store, _projectionShard.EventFilters);
_hopper = _projectionShard.Start(this, _logger, _cancellationSource.Token);
_loader.LinkTo(_hopper);
var lastCommitted = await _store.Events.ProjectionProgressFor(_projectionShard.ProjectionOrShardName);
_commandBlock.Post(Command.Started(tracker.HighWaterMark, lastCommitted));
_subscription = _tracker.Subscribe(this);
_logger.LogInformation($"Projection agent for '{_projectionShard.ProjectionOrShardName}' has started from sequence {lastCommitted} and a high water mark of {tracker.HighWaterMark}");
Status = AgentStatus.Running;
Position = lastCommitted;
return(lastCommitted);
}