async Task <IStreamProcessorState> GetOrCreateStreamProcessorState(IStreamProcessorId streamProcessorId, IStreamProcessorState initialState, CancellationToken cancellationToken)
{
var tryGetStreamProcessorState = await _streamProcessorStates.TryGetFor(streamProcessorId, cancellationToken).ConfigureAwait(false);
if (tryGetStreamProcessorState.Success)
{
return(tryGetStreamProcessorState.Result);
}
await _streamProcessorStates.Persist(streamProcessorId, initialState, cancellationToken).ConfigureAwait(false);
return(initialState);
}
/// <summary>
/// Initializes a new instance of the <see cref="ScopedStreamProcessor"/> class.
/// </summary>
/// <param name="tenantId">The <see cref="TenantId"/>.</param>
/// <param name="streamProcessorId">The <see cref="IStreamProcessorId" />.</param>
/// <param name="sourceStreamDefinition">The source stream <see cref="IStreamDefinition" />.</param>
/// <param name="initialState">The <see cref="StreamProcessorState" />.</param>
/// <param name="processor">An <see cref="IEventProcessor" /> to process the event.</param>
/// <param name="streamProcessorStates">The <see cref="IResilientStreamProcessorStateRepository" />.</param>
/// <param name="eventsFromStreamsFetcher">The<see cref="ICanFetchEventsFromStream" />.</param>
/// <param name="executionContext">The <see cref="ExecutionContext"/> of the stream processor.</param>
/// <param name="eventFetcherPolicies">The policies to use while fetching events.</param>
/// <param name="eventWatcher">The <see cref="IStreamEventWatcher" /> to wait for events to be available in stream.</param>
/// <param name="timeToRetryGetter">The <see cref="ICanGetTimeToRetryFor{T}" /> <see cref="StreamProcessorState" />.</param>
/// <param name="logger">An <see cref="ILogger" /> to log messages.</param>
public ScopedStreamProcessor(
TenantId tenantId,
IStreamProcessorId streamProcessorId,
IStreamDefinition sourceStreamDefinition,
StreamProcessorState initialState,
IEventProcessor processor,
IResilientStreamProcessorStateRepository streamProcessorStates,
ICanFetchEventsFromStream eventsFromStreamsFetcher,
ExecutionContext executionContext,
IEventFetcherPolicies eventFetcherPolicies,
IStreamEventWatcher eventWatcher,
ICanGetTimeToRetryFor <StreamProcessorState> timeToRetryGetter,
ILogger logger)
: base(tenantId, streamProcessorId, sourceStreamDefinition, initialState, processor, eventsFromStreamsFetcher, executionContext, eventFetcherPolicies, eventWatcher, logger)
{
_streamProcessorStates = streamProcessorStates;
_timeToRetryGetter = timeToRetryGetter;
}
/// <inheritdoc />
public async Task <AbstractScopedStreamProcessor> Create(
IStreamDefinition streamDefinition,
IStreamProcessorId streamProcessorId,
IEventProcessor eventProcessor,
ExecutionContext executionContext,
CancellationToken cancellationToken)
{
var processorState = await GetOrCreateStreamProcessorState(
streamProcessorId,
streamDefinition.Partitioned
?Partitioned.StreamProcessorState.New
: StreamProcessorState.New,
cancellationToken)
.ConfigureAwait(false);
AbstractScopedStreamProcessor streamProcessor;
if (streamDefinition.Partitioned)
{
if (processorState is not Partitioned.StreamProcessorState partitionedProcessorState)
{
throw new ExpectedPartitionedStreamProcessorState(streamProcessorId);
}
var eventFetcher = await _eventFetchers.GetPartitionedFetcherFor(eventProcessor.Scope, streamDefinition, cancellationToken).ConfigureAwait(false);
streamProcessor = _createPartitionedStreamProcessor(streamDefinition, streamProcessorId, eventFetcher, eventProcessor, partitionedProcessorState, executionContext);
}
else
{
if (processorState is not StreamProcessorState unpartitionedProcessorState)
{
throw new ExpectedUnpartitionedStreamProcessorState(streamProcessorId);
}
var eventFetcher = await _eventFetchers.GetFetcherFor(eventProcessor.Scope, streamDefinition, cancellationToken).ConfigureAwait(false);
streamProcessor = _createUnpartitionedStreamProcessor(streamDefinition, streamProcessorId, eventFetcher, eventProcessor, unpartitionedProcessorState, executionContext);
}
NotifyStream(streamProcessorId.ScopeId, streamDefinition, processorState.Position);
return(streamProcessor);
}
