C#•2y ago

Reporting download progress with IAsyncEnumerable

Is reporting progress with an IAsyncEnumerable<T> weird? I have the following:

public interface IDownloadService
{
    IAsyncEnumerable<DownloadProgress> DownloadAsync(CancellationToken cancellationToken = default);
}

public interface IDownloadService
{
    IAsyncEnumerable<DownloadProgress> DownloadAsync(CancellationToken cancellationToken = default);
}

Is this a weird thing to do? I know it will "pause" the download in-between each progress yield (that is yield return new DownloadProgress(...)). But I kind of like the way you consume it:

var enumerable = _downloadService.DownloadAsync(cancellationToken);

await foreach (var progress in enumerable.WithCancellation(cancellationToken))
{
    // Use 'progress' here...
}

var enumerable = _downloadService.DownloadAsync(cancellationToken);

await foreach (var progress in enumerable.WithCancellation(cancellationToken))
{
    // Use 'progress' here...
}

What are your thoughts?

2 Replies

Tvde1•2y ago

it's a little weird. You don't want logging or UI updates to hamper your downloading I'd probably do this with a Rx subject. You can probably configure those to invoke observers on a different Task thread

mrphil2105•2y ago

I don't use Rx I might just use a regular event when

Gaming

Programming

Reporting download progress with IAsyncEnumerable