SftpExtensions.cs

public static class SftpExtensions
{
    /// <remarks> 
    /// unfortunately the ssh library doesn't expose a modern async api
    /// that supports cancellation via CancellationToken
    /// so we have to wrap the APM pattern with a TaskCompletionSource
    /// </remarks>
    public static Task UploadFileAsync(this SftpClient sftpClient, Stream input, string path, bool canOverride, Action<ulong> uploadCallback = null, CancellationToken cancellationToken = default(CancellationToken))
    {
        var tcs = new TaskCompletionSource<SftpUploadAsyncResult>();
        var uploadResult = (SftpUploadAsyncResult)sftpClient.BeginUploadFile(input, path, canOverride, ar =>
       {
           var ar2 = (SftpUploadAsyncResult)ar;

           try
           {
               ar2.EndInvoke();

               if (ar2.IsUploadCanceled)
               {
                   tcs.SetCanceled();
               }
               else if (ar2.IsCompleted)
               {
                   tcs.SetResult(ar2);
               }
           }
           catch (Exception ex)
           {
               tcs.SetException(ex);
           }
       }, null, uploadCallback);

        cancellationToken.Register(() => uploadResult.IsUploadCanceled = true);
        return tcs.Task;
    }

}

EndInvoke is not a public method anymore and it is internal. Is there any alternative or replacement? Thanks in advance.

You can use _client.EndUploadFile(ar2); instead.