fix(row): add lock for ToMap to avoid concurrent map write

It is possible to have multiple sinks call ToMap at once

Signed-off-by: Jiyong Huang <[email protected]>

internal/xsql/row.go

@@ -220,7 +220,7 @@ type Tuple struct {
 	Metadata  Metadata // immutable
 
 	AffiliateRow
-
+	lock      sync.Mutex             // lock for the cachedMap, because it is possible to access by multiple sinks
 	cachedMap map[string]interface{} // clone of the row and cached for performance
 }
 
@@ -230,6 +230,7 @@ var _ TupleRow = &Tuple{}
 type JoinTuple struct {
 	Tuples []TupleRow // The content is immutable, but the slice may be add or removed
 	AffiliateRow
+	lock      sync.Mutex
 	cachedMap map[string]interface{} // clone of the row and cached for performance of toMap
 }
 
@@ -244,6 +245,7 @@ type GroupedTuples struct {
 	Content []TupleRow
 	*WindowRange
 	AffiliateRow
+	lock      sync.Mutex
 	cachedMap map[string]interface{} // clone of the row and cached for performance of toMap
 }
 
@@ -339,6 +341,8 @@ func (t *Tuple) Clone() TupleRow {
 
 // ToMap should only use in sink.
 func (t *Tuple) ToMap() map[string]interface{} {
+	t.lock.Lock()
+	defer t.lock.Unlock()
 	if t.AffiliateRow.IsEmpty() {
 		return t.Message
 	}
@@ -487,6 +491,8 @@ func (jt *JoinTuple) Clone() TupleRow {
 }
 
 func (jt *JoinTuple) ToMap() map[string]interface{} {
+	jt.lock.Lock()
+	defer jt.lock.Unlock()
 	if jt.cachedMap == nil { // clone the message
 		m := make(map[string]interface{})
 		for i := len(jt.Tuples) - 1; i >= 0; i-- {
@@ -544,6 +550,8 @@ func (s *GroupedTuples) All(_ string) (Message, bool) {
 }
 
 func (s *GroupedTuples) ToMap() map[string]interface{} {
+	s.lock.Lock()
+	defer s.lock.Unlock()
 	if s.cachedMap == nil {
 		m := make(map[string]interface{})
 		for k, v := range s.Content[0].ToMap() {