diff --git a/client.go b/client.go
index 5a1ed97c1..271c8d170 100644
--- a/client.go
+++ b/client.go
@@ -70,64 +70,64 @@ var _ InternalQueryClient = newNopInternalQueryClient()
 
 //===============
 
-type NopInternalClient struct{}
+type nopInternalClient struct{}
 
-func newNopInternalClient() NopInternalClient {
-	return NopInternalClient{}
+func newNopInternalClient() nopInternalClient {
+	return nopInternalClient{}
 }
 
 var _ InternalClient = newNopInternalClient()
 
-func (n NopInternalClient) MaxShardByIndex(context.Context) (map[string]uint64, error) {
+func (n nopInternalClient) MaxShardByIndex(context.Context) (map[string]uint64, error) {
 	return nil, nil
 }
-func (n NopInternalClient) Schema(ctx context.Context) ([]*IndexInfo, error) { return nil, nil }
-func (n NopInternalClient) CreateIndex(ctx context.Context, index string, opt IndexOptions) error {
+func (n nopInternalClient) Schema(ctx context.Context) ([]*IndexInfo, error) { return nil, nil }
+func (n nopInternalClient) CreateIndex(ctx context.Context, index string, opt IndexOptions) error {
 	return nil
 }
-func (n NopInternalClient) FragmentNodes(ctx context.Context, index string, shard uint64) ([]*Node, error) {
+func (n nopInternalClient) FragmentNodes(ctx context.Context, index string, shard uint64) ([]*Node, error) {
 	return nil, nil
 }
-func (n NopInternalClient) Query(ctx context.Context, index string, queryRequest *QueryRequest) (*QueryResponse, error) {
+func (n nopInternalClient) Query(ctx context.Context, index string, queryRequest *QueryRequest) (*QueryResponse, error) {
 	return nil, nil
 }
-func (n NopInternalClient) QueryNode(ctx context.Context, uri *URI, index string, queryRequest *QueryRequest) (*QueryResponse, error) {
+func (n nopInternalClient) QueryNode(ctx context.Context, uri *URI, index string, queryRequest *QueryRequest) (*QueryResponse, error) {
 	return nil, nil
 }
-func (n NopInternalClient) Import(ctx context.Context, index, field string, shard uint64, bits []Bit) error {
+func (n nopInternalClient) Import(ctx context.Context, index, field string, shard uint64, bits []Bit) error {
 	return nil
 }
-func (n NopInternalClient) ImportK(ctx context.Context, index, field string, bits []Bit) error {
+func (n nopInternalClient) ImportK(ctx context.Context, index, field string, bits []Bit) error {
 	return nil
 }
-func (n NopInternalClient) EnsureIndex(ctx context.Context, name string, options IndexOptions) error {
+func (n nopInternalClient) EnsureIndex(ctx context.Context, name string, options IndexOptions) error {
 	return nil
 }
-func (n NopInternalClient) EnsureField(ctx context.Context, indexName string, fieldName string) error {
+func (n nopInternalClient) EnsureField(ctx context.Context, indexName string, fieldName string) error {
 	return nil
 }
-func (n NopInternalClient) ImportValue(ctx context.Context, index, field string, shard uint64, vals []FieldValue) error {
+func (n nopInternalClient) ImportValue(ctx context.Context, index, field string, shard uint64, vals []FieldValue) error {
 	return nil
 }
-func (n NopInternalClient) ExportCSV(ctx context.Context, index, field string, shard uint64, w io.Writer) error {
+func (n nopInternalClient) ExportCSV(ctx context.Context, index, field string, shard uint64, w io.Writer) error {
 	return nil
 }
-func (n NopInternalClient) CreateField(ctx context.Context, index, field string) error { return nil }
-func (n NopInternalClient) FragmentBlocks(ctx context.Context, uri *URI, index, field string, shard uint64) ([]FragmentBlock, error) {
+func (n nopInternalClient) CreateField(ctx context.Context, index, field string) error { return nil }
+func (n nopInternalClient) FragmentBlocks(ctx context.Context, uri *URI, index, field string, shard uint64) ([]FragmentBlock, error) {
 	return nil, nil
 }
-func (n NopInternalClient) BlockData(ctx context.Context, uri *URI, index, field string, shard uint64, block int) ([]uint64, []uint64, error) {
+func (n nopInternalClient) BlockData(ctx context.Context, uri *URI, index, field string, shard uint64, block int) ([]uint64, []uint64, error) {
 	return nil, nil, nil
 }
-func (n NopInternalClient) ColumnAttrDiff(ctx context.Context, uri *URI, index string, blks []AttrBlock) (map[uint64]map[string]interface{}, error) {
+func (n nopInternalClient) ColumnAttrDiff(ctx context.Context, uri *URI, index string, blks []AttrBlock) (map[uint64]map[string]interface{}, error) {
 	return nil, nil
 }
-func (n NopInternalClient) RowAttrDiff(ctx context.Context, uri *URI, index, field string, blks []AttrBlock) (map[uint64]map[string]interface{}, error) {
+func (n nopInternalClient) RowAttrDiff(ctx context.Context, uri *URI, index, field string, blks []AttrBlock) (map[uint64]map[string]interface{}, error) {
 	return nil, nil
 }
-func (n NopInternalClient) SendMessage(ctx context.Context, uri *URI, msg []byte) error {
+func (n nopInternalClient) SendMessage(ctx context.Context, uri *URI, msg []byte) error {
 	return nil
 }
-func (n NopInternalClient) RetrieveShardFromURI(ctx context.Context, index, field string, shard uint64, uri URI) (io.ReadCloser, error) {
+func (n nopInternalClient) RetrieveShardFromURI(ctx context.Context, index, field string, shard uint64, uri URI) (io.ReadCloser, error) {
 	return nil, nil
 }