diff --git a/go.mod b/go.mod
index 59c91607dc6a0db3add4884d90645a72cd4d880c..13f23f5acdf4fc5ed89af9121fa377c33246a783 100644
--- a/go.mod
+++ b/go.mod
@@ -5,7 +5,6 @@ require (
 	github.com/afex/hystrix-go v0.0.0-20180502004556-fa1af6a1f4f5
 	github.com/aliyun/alibaba-cloud-sdk-go v0.0.0-20190802083043-4cd0c391755e // indirect
 	github.com/apache/dubbo-go-hessian2 v1.2.5-0.20191029001541-894e45c9aaaa
-	github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869
 	github.com/buger/jsonparser v0.0.0-20181115193947-bf1c66bbce23 // indirect
 	github.com/coreos/bbolt v1.3.3 // indirect
 	github.com/coreos/etcd v3.3.13+incompatible
diff --git a/protocol/grpc/protoc-gen-dubbo/main.go b/protocol/grpc/protoc-gen-dubbo/main.go
index e12ceca756117a5af9dd3c2dac323297e28e95fb..b2f0e82f74a4d3c1a7013714cd18d83562baff71 100644
--- a/protocol/grpc/protoc-gen-dubbo/main.go
+++ b/protocol/grpc/protoc-gen-dubbo/main.go
@@ -28,7 +28,7 @@ import (
 	_ "github.com/golang/protobuf/protoc-gen-go/grpc"
 )
 
-import(
+import (
 	_ "github.com/apache/dubbo-go/protocol/grpc/protoc-gen-dubbo/plugin/dubbo"
 )