lxd/storage.go
func StorageProgressWriter(op *operation, key string, description string) func(io.WriteCloser) io.WriteCloser {
	return func(writer io.WriteCloser) io.WriteCloser {
		if op == nil {
			return writer
		}

		progress := func(progressInt int64, speedInt int64) {
			progressWrapperRender(op, key, description, progressInt, speedInt)
		}

		writePipe := &ioprogress.ProgressWriter{
			WriteCloser: writer,
			Tracker: &ioprogress.ProgressTracker{
				Handler: progress,
			},
		}

		return writePipe
	}
}
func StorageProgressWriter(op *operation, key string, description string) func(io.WriteCloser) io.WriteCloser {
	return func(writer io.WriteCloser) io.WriteCloser {
		if op == nil {
			return writer
		}

		progress := func(progressInt int64, speedInt int64) {
			progressWrapperRender(op, key, description, progressInt, speedInt)
		}

		writePipe := &ioprogress.ProgressWriter{
			WriteCloser: writer,
			Tracker: &ioprogress.ProgressTracker{
				Handler: progress,
			},
		}

		return writePipe
	}
}
// StorageProgressWriter reports the write progress.