Fix wrong error handling in volume.tier.upload when stream == nil but copyErr != nil (#6867)

weed/shell/command_volume_tier_upload.go

@@ -147,11 +147,15 @@ func uploadDatToRemoteTier(grpcDialOption grpc.DialOption, writer io.Writer, vol
 			KeepLocalDatFile:       keepLocalDatFile,
 		})
 
-		if stream == nil && copyErr == nil {
-			// when the volume is already uploaded, VolumeTierMoveDatToRemote will return nil stream and nil error
-			// so we should directly return in this case
-			fmt.Fprintf(writer, "volume %v already uploaded", volumeId)
-			return nil
+		if stream == nil {
+			if copyErr == nil {
+				// when the volume is already uploaded, VolumeTierMoveDatToRemote will return nil stream and nil error
+				// so we should directly return in this caseAdd commentMore actions
+				fmt.Fprintf(writer, "volume %v already uploaded", volumeId)
+				return nil
+			} else {
+				return copyErr
+			}
 		}
 		var lastProcessed int64
 		for {