Implement Alibaba Cloud OSS gateway support (#5103)

vendor/github.com/aliyun/aliyun-oss-go-sdk/oss/progress.go

@@ -0,0 +1,105 @@
+package oss
+
+import "io"
+
+// ProgressEventType transfer progress event type
+type ProgressEventType int
+
+const (
+	// TransferStartedEvent transfer started, set TotalBytes
+	TransferStartedEvent ProgressEventType = 1 + iota
+	// TransferDataEvent transfer data, set ConsumedBytes anmd TotalBytes
+	TransferDataEvent
+	// TransferCompletedEvent transfer completed
+	TransferCompletedEvent
+	// TransferFailedEvent transfer encounters an error
+	TransferFailedEvent
+)
+
+// ProgressEvent progress event
+type ProgressEvent struct {
+	ConsumedBytes int64
+	TotalBytes    int64
+	EventType     ProgressEventType
+}
+
+// ProgressListener listen progress change
+type ProgressListener interface {
+	ProgressChanged(event *ProgressEvent)
+}
+
+// -------------------- private --------------------
+
+func newProgressEvent(eventType ProgressEventType, consumed, total int64) *ProgressEvent {
+	return &ProgressEvent{
+		ConsumedBytes: consumed,
+		TotalBytes:    total,
+		EventType:     eventType}
+}
+
+// publishProgress
+func publishProgress(listener ProgressListener, event *ProgressEvent) {
+	if listener != nil && event != nil {
+		listener.ProgressChanged(event)
+	}
+}
+
+type readerTracker struct {
+	completedBytes int64
+}
+
+type teeReader struct {
+	reader        io.Reader
+	writer        io.Writer
+	listener      ProgressListener
+	consumedBytes int64
+	totalBytes    int64
+	tracker       *readerTracker
+}
+
+// TeeReader returns a Reader that writes to w what it reads from r.
+// All reads from r performed through it are matched with
+// corresponding writes to w.  There is no internal buffering -
+// the write must complete before the read completes.
+// Any error encountered while writing is reported as a read error.
+func TeeReader(reader io.Reader, writer io.Writer, totalBytes int64, listener ProgressListener, tracker *readerTracker) io.Reader {
+	return &teeReader{
+		reader:        reader,
+		writer:        writer,
+		listener:      listener,
+		consumedBytes: 0,
+		totalBytes:    totalBytes,
+		tracker:       tracker,
+	}
+}
+
+func (t *teeReader) Read(p []byte) (n int, err error) {
+	n, err = t.reader.Read(p)
+
+	// read encountered error
+	if err != nil && err != io.EOF {
+		event := newProgressEvent(TransferFailedEvent, t.consumedBytes, t.totalBytes)
+		publishProgress(t.listener, event)
+	}
+
+	if n > 0 {
+		t.consumedBytes += int64(n)
+		// crc
+		if t.writer != nil {
+			if n, err := t.writer.Write(p[:n]); err != nil {
+				return n, err
+			}
+		}
+		// progress
+		if t.listener != nil {
+			event := newProgressEvent(TransferDataEvent, t.consumedBytes, t.totalBytes)
+			publishProgress(t.listener, event)
+		}
+		// track
+		if t.tracker != nil {
+			t.tracker.completedBytes = t.consumedBytes
+		}
+	}
+
+	return
+}