br: Fix RangeTree.GetIncompleteRange when the rangeTree is empty.

br/pkg/backup/push.go

@@ -119,7 +119,6 @@ func (push *pushDown) pushBackup(
 		close(push.respCh)
 	}()
 
-	regionErrorIngestedOnce := false
 	for {
 		select {
 		case respAndStore, ok := <-push.respCh:
@@ -151,19 +150,16 @@ func (push *pushDown) pushBackup(
 				}
 			})
 			failpoint.Inject("tikv-region-error", func(val failpoint.Value) {
-				if !regionErrorIngestedOnce {
-					msg := val.(string)
-					logutil.CL(ctx).Debug("failpoint tikv-regionh-error injected.", zap.String("msg", msg))
-					resp.Error = &backuppb.Error{
-						// Msg: msg,
-						Detail: &backuppb.Error_RegionError{
-							RegionError: &errorpb.Error{
-								Message: msg,
-							},
+				msg := val.(string)
+				logutil.CL(ctx).Debug("failpoint tikv-region-error injected.", zap.String("msg", msg))
+				resp.Error = &backuppb.Error{
+					// Msg: msg,
+					Detail: &backuppb.Error_RegionError{
+						RegionError: &errorpb.Error{
+							Message: msg,
 						},
-					}
+					},
 				}
-				regionErrorIngestedOnce = true
 			})
 			if resp.GetError() == nil {
 				// None error means range has been backuped successfully.

br/pkg/rtree/rtree.go

@@ -185,17 +185,19 @@ func (rangeTree *RangeTree) GetIncompleteRange(
 		return []Range{}
 	}
 	incomplete := make([]Range, 0, 64)
-	requsetRange := Range{StartKey: startKey, EndKey: endKey}
+	requestRange := Range{StartKey: startKey, EndKey: endKey}
 	lastEndKey := startKey
 	pviot := &Range{StartKey: startKey}
 	if first := rangeTree.Find(pviot); first != nil {
 		pviot.StartKey = first.StartKey
 	}
+	pviotNotFound := true
 	rangeTree.AscendGreaterOrEqual(pviot, func(i btree.Item) bool {
+		pviotNotFound = false
 		rg := i.(*Range)
 		if bytes.Compare(lastEndKey, rg.StartKey) < 0 {
 			start, end, isIntersect :=
-				requsetRange.Intersect(lastEndKey, rg.StartKey)
+				requestRange.Intersect(lastEndKey, rg.StartKey)
 			if isIntersect {
 				// There is a gap between the last item and the current item.
 				incomplete =
@@ -207,9 +209,10 @@ func (rangeTree *RangeTree) GetIncompleteRange(
 	})
 
 	// Check whether we need append the last range
-	if !bytes.Equal(lastEndKey, endKey) && len(lastEndKey) != 0 &&
-		(len(endKey) == 0 || bytes.Compare(lastEndKey, endKey) < 0) {
-		start, end, isIntersect := requsetRange.Intersect(lastEndKey, endKey)
+	if pviotNotFound ||
+		(!bytes.Equal(lastEndKey, endKey) && len(lastEndKey) != 0 &&
+			(len(endKey) == 0 || bytes.Compare(lastEndKey, endKey) < 0)) {
+		start, end, isIntersect := requestRange.Intersect(lastEndKey, endKey)
 		if isIntersect {
 			incomplete =
 				append(incomplete, Range{StartKey: start, EndKey: end})

br/pkg/rtree/rtree_test.go

@@ -47,6 +47,10 @@ func TestRangeTree(t *testing.T) {
 		}
 	}
 
+	assertIncomplete([]byte(""), []byte("b"), []rtree.Range{{StartKey: []byte(""), EndKey: []byte("b")}})
+	assertIncomplete([]byte(""), []byte(""), []rtree.Range{{StartKey: []byte(""), EndKey: []byte("")}})
+	assertIncomplete([]byte("b"), []byte(""), []rtree.Range{{StartKey: []byte("b"), EndKey: []byte("")}})
+
 	range0 := newRange([]byte(""), []byte("a"))
 	rangeA := newRange([]byte("a"), []byte("b"))
 	rangeB := newRange([]byte("b"), []byte("c"))
@@ -61,6 +65,7 @@ func TestRangeTree(t *testing.T) {
 			{StartKey: []byte(""), EndKey: []byte("a")},
 			{StartKey: []byte("b"), EndKey: []byte("")},
 		})
+	assertIncomplete([]byte("b"), []byte(""), []rtree.Range{{StartKey: []byte("b"), EndKey: []byte("")}})
 
 	rangeTree.Update(*rangeC)
 	require.Equal(t, 2, rangeTree.Len())

br/tests/br_rawkv/run.sh

@@ -52,8 +52,7 @@ test_full_rawkv() {
 
     checksum_full=$(checksum $check_range_start $check_range_end)
     # backup current state of key-values
-    # raw backup is not working with range [nil, nil]. TODO: fix it.
-    run_br --pd $PD_ADDR backup raw -s "local://$BACKUP_FULL" --crypter.method "aes128-ctr" --crypter.key "0123456789abcdef0123456789abcdef" --start $check_range_start --format hex
+    run_br --pd $PD_ADDR backup raw -s "local://$BACKUP_FULL" --crypter.method "aes128-ctr" --crypter.key "0123456789abcdef0123456789abcdef"
 
     clean $check_range_start $check_range_end
     # Ensure the data is deleted
@@ -63,7 +62,7 @@ test_full_rawkv() {
         fail_and_exit
     fi
 
-    run_br --pd $PD_ADDR restore raw -s "local://$BACKUP_FULL" --crypter.method "aes128-ctr" --crypter.key "0123456789abcdef0123456789abcdef" --start $check_range_start --format hex
+    run_br --pd $PD_ADDR restore raw -s "local://$BACKUP_FULL" --crypter.method "aes128-ctr" --crypter.key "0123456789abcdef0123456789abcdef"
     checksum_new=$(checksum $check_range_start $check_range_end)
     if [ "$checksum_new" != "$checksum_full" ];then
         echo "failed to restore"
@@ -185,5 +184,7 @@ run_test() {
 
 run_test ""
 
-# ingest "region error" to trigger fineGrainedBackup
+# ingest "region error" to trigger fineGrainedBackup, only one region error.
+run_test "github.com/pingcap/tidb/br/pkg/backup/tikv-region-error=1*return(\"region error\")"
+# all regions failed.
 run_test "github.com/pingcap/tidb/br/pkg/backup/tikv-region-error=return(\"region error\")"