static Task PostAllFilePathsAsync(IEnumerable<CollectionPath> paths, Func<FileInfo, bool> filePredicate,
ITargetBlock<AnnotatedPath> filePathTargetBlock, CancellationToken cancellationToken)
{
var scanTasks = paths
.Select<CollectionPath, Task>(path =>
Task.Factory.StartNew(
async () =>
{
foreach (var file in PathUtil.ScanDirectory(path.Path, filePredicate))
{
if (cancellationToken.IsCancellationRequested)
break;
var relativePath = PathUtil.MakeRelativePath(path.Path, file.FullName);
var annotatedPath = new AnnotatedPath { FileInfo = file, Collection = path.Collection ?? path.Path, RelativePath = relativePath };
await filePathTargetBlock.SendAsync(annotatedPath, cancellationToken).ConfigureAwait(false);
}
},
cancellationToken,
TaskCreationOptions.DenyChildAttach | TaskCreationOptions.LongRunning | TaskCreationOptions.RunContinuationsAsynchronously,
TaskScheduler.Default));
var task = Task.WhenAll(scanTasks);
var completeTask = task.ContinueWith(_ => filePathTargetBlock.Complete());
TaskCollector.Default.Add(completeTask, "PostAllFilePathsAsync");
return task;
}
Task SetAnnotatedPathAsync(AnnotatedPath annotatedPath)
{
var pathFingerprint = GetPathFingerprint(annotatedPath.FileInfo.FullName);
var key = Tuple.Create(annotatedPath.Collection, annotatedPath.RelativePath);
IFileFingerprint fileFingerprint;
lock (pathFingerprint)
{
if (pathFingerprint.AnnotatedPaths.ContainsKey(key))
throw new InvalidOperationException("Duplicate collection/relative path for " + annotatedPath.FileInfo.FullName);
pathFingerprint.AnnotatedPaths[key] = annotatedPath;
fileFingerprint = pathFingerprint.FileFingerprint;
}
if (null == fileFingerprint)
return Task.CompletedTask;
return _targetBlock.SendAsync(Tuple.Create(annotatedPath, fileFingerprint));
}