Add missing error check in addBlock

Qi Xiao · Qi Xiao · commit 9ab6bc07cc67 · 2019-02-26T21:31:26.000+08:00
diff --git a/sqlchain/observer/service.go b/sqlchain/observer/service.go
@@ -306,6 +306,10 @@ func (s *Service) addQueryTracker(dbID proto.DatabaseID, height int32, offset in
 
 func (s *Service) addBlock(dbID proto.DatabaseID, count int32, b *types.Block) (err error) {
 	instance, err := s.getUpstream(dbID)
+	if err != nil {
+		return
+	}
+
 	h := int32(b.Timestamp().Sub(instance.GenesisBlock.Timestamp()) / conf.GConf.SQLChainPeriod)
 	key := utils.ConcatAll(int32ToBytes(h), b.BlockHash().AsBytes(), int32ToBytes(count))
 	// It's actually `countToBytes`
