add grpcConnection to type Node and close it in Stop method (#47)

node/remote/node.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/cosmos/cosmos-sdk/codec"
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	"google.golang.org/grpc"
 
 	constypes "github.com/tendermint/tendermint/consensus/types"
 	tmjson "github.com/tendermint/tendermint/libs/json"
@@ -34,6 +35,7 @@ type Node struct {
 	codec           codec.Marshaler
 	client          *httpclient.HTTP
 	txServiceClient tx.ServiceClient
+	grpcConnection  *grpc.ClientConn
 }
 
 // NewNode allows to build a new Node instance
@@ -71,6 +73,7 @@ func NewNode(cfg *Details, codec codec.Marshaler) (*Node, error) {
 
 		client:          rpcClient,
 		txServiceClient: tx.NewServiceClient(grpcConnection),
+		grpcConnection:  grpcConnection,
 	}, nil
 }
 
@@ -201,4 +204,9 @@ func (cp *Node) Stop() {
 	if err != nil {
 		panic(fmt.Errorf("error while stopping proxy: %s", err))
 	}
+
+	err = cp.grpcConnection.Close()
+	if err != nil {
+		panic(fmt.Errorf("error while closing gRPC connection: %s", err))
+	}
 }