Add e2e test
diff --git a/core/kg/go.mod b/core/kg/go.mod
index 990e6e9..f6bf84a 100644
--- a/core/kg/go.mod
+++ b/core/kg/go.mod
@@ -9,6 +9,7 @@
 	github.com/jmoiron/sqlx v1.3.1
 	github.com/pkg/errors v0.9.1
 	github.com/spf13/cobra v1.1.3
+	github.com/stretchr/testify v1.7.0
 	go.uber.org/zap v1.16.0
 	golang.org/x/sys v0.0.0-20200122134326-e047566fdf82 // indirect
 	golang.org/x/tools v0.0.0-20200313205530-4303120df7d8 // indirect