Azure-sdk-for-net: Storage: Add progress handling for upload/download

[tg-msft]

BlobBaseClient.StagedDownloadAsync and BlobClient.StagedUploadAsync have commented out progress handlers.

[tg-msft]

Adding customer-reported tag here since I closed #9216 as a duplicate.

[Petermarcu]

Is this one fixed?

[msftbot[bot]]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @xgithubtriage.

[seanmcc-msft]

@Petermarcu, IIRC we have progress reporting for all upload APIs now, but not downloads.

[blueww]

When can we add progress reporting for BlobBaseClient.DownloadToAsync()?
We plan to use this API in Blob Download cmdlet in PSH.

[ModernRonin]

being able to pass an IProgress<> to .DownloadToAsync(), just as we can with .UploadAsync(), would be very helpful.

Is this currently planned? If yes, is there a milestone/timeline? I'm asking because I need to support an API that expects to monitor the progress of downloads and I'm wondering whether it makes sense to work around the missing progress support by implementing a wrapper around it myself - for which I probably have to turn off parallelism which is not nice - or whether the support will come to the Azure.Storage.Blobs in time for my own deadline.

Thanks,
MR

[koskit]

This might help .NET Developers:

public static Task Download(this BlobClient blobClient, string localPath, IProgress<long> progressPercentage)
{
    Response<BlobProperties> blobProperties = blobClient.GetProperties();
    long blobContentLength = blobProperties.Value.ContentLength;

    using (FileStream stream = File.Create(localPath))
    {
        Task<Response> downloadTask = blobClient.DownloadToAsync(stream);

        //Read how many bytes on stream.
        while (stream.Length < blobContentLength)
        {
            progressPercentage.Report(stream.Length * 100 / blobContentLength);
        }

        return downloadTask;
    }
}

In my code, I export the percentage (x%) and not the downloaded bytes ( you can see I calculate stream.Length * 100 / blobContentLength ). Hope it helps someone