private (ITargetBlock <string>, Task) CreatePipeline()
{
var linkOptions = new DataflowLinkOptions {
PropagateCompletion = true
};
TransformManyBlock <object, IImage> fetchBlock = new TransformManyBlock <object, IImage>(_ => _functions.Fetch(_options.Value.Location), new ExecutionDataflowBlockOptions {
BoundedCapacity = 2, MaxDegreeOfParallelism = 1
});
TransformManyBlock <IImage, IImage> detectFacesBlock = new TransformManyBlock <IImage, IImage>(source => _functions.ExtractFaces(source));
TransformManyBlock <IImage, IRecognition> recogniseFacesBlock = new TransformManyBlock <IImage, IRecognition>(source => _functions.RecogniseFaces(source));
TransformBlock <IRecognition, IPersistedRecognition> persistRecognitionBlock = new TransformBlock <IRecognition, IPersistedRecognition>(recognition => _functions.PersistRecognition(recognition), new ExecutionDataflowBlockOptions {
BoundedCapacity = 10, MaxDegreeOfParallelism = 1
});
ActionBlock <IPersistedRecognition> notifyRecognitionBlock = new ActionBlock <IPersistedRecognition>(recognition => _functions.NotifyRecognition(recognition), new ExecutionDataflowBlockOptions {
BoundedCapacity = 10, MaxDegreeOfParallelism = 1
});
fetchBlock.LinkTo(detectFacesBlock, linkOptions);
detectFacesBlock.LinkTo(recogniseFacesBlock, linkOptions);
recogniseFacesBlock.LinkTo(persistRecognitionBlock, linkOptions);
persistRecognitionBlock.LinkTo(notifyRecognitionBlock, linkOptions);
return(fetchBlock, notifyRecognitionBlock.Completion);
}