port unique constraint error into dm

indexedDb/impl/channels/implementation.go

@@ -417,8 +417,7 @@ func (w *wasmModel) receiveHelper(
 
 	// Store message to database
 	result, err := impl.Put(w.db, messageStoreName, messageObj)
-	if err != nil && !strings.Contains(err.Error(),
-		"at least one key does not satisfy the uniqueness requirements") {
+	if err != nil && !strings.Contains(err.Error(), impl.ErrUniqueConstraint) {
 		// Only return non-unique constraint errors so that the case
 		// below this one can be hit and handle duplicate entries properly.
 		return 0, errors.Errorf("Unable to put Message: %+v", err)

indexedDb/impl/dm/implementation.go

@@ -288,7 +288,9 @@ func (w *wasmModel) receiveHelper(
 
 	// Store message to database
 	result, err := impl.Put(w.db, messageStoreName, messageObj)
-	if err != nil {
+	if err != nil && !strings.Contains(err.Error(), impl.ErrUniqueConstraint) {
+		// Only return non-unique constraint errors so that the case
+		// below this one can be hit and handle duplicate entries properly.
 		return 0, errors.Errorf("Unable to put Message: %+v", err)
 	}
 

indexedDb/impl/utils.go

@@ -30,6 +30,9 @@ const (
 
 	// ErrDoesNotExist is an error string for got undefined on Get operations.
 	ErrDoesNotExist = "result is undefined"
+
+	// ErrUniqueConstraint is an error string for failed uniqueness inserts.
+	ErrUniqueConstraint = "at least one key does not satisfy the uniqueness requirements"
 )
 
 // NewContext builds a context for indexedDb operations.