diff --git a/examples/addsvc/pb/addsvc.pb.go b/examples/addsvc/pb/addsvc.pb.go
index 0e8cff5..a685eef 100644
--- a/examples/addsvc/pb/addsvc.pb.go
+++ b/examples/addsvc/pb/addsvc.pb.go
@@ -93,7 +93,7 @@
 
 // This is a compile-time assertion to ensure that this generated file
 // is compatible with the grpc package it is being compiled against.
-const _ = grpc.SupportPackageIsVersion3
+const _ = grpc.SupportPackageIsVersion4
 
 // Client API for Add service
 
@@ -193,13 +193,13 @@
 		},
 	},
 	Streams:  []grpc.StreamDesc{},
-	Metadata: fileDescriptor0,
+	Metadata: "addsvc.proto",
 }
 
 func init() { proto.RegisterFile("addsvc.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
-	// 188 bytes of a gzipped FileDescriptorProto
+	// 189 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0xe2, 0xe2, 0x49, 0x4c, 0x49, 0x29,
 	0x2e, 0x4b, 0xd6, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0x62, 0x2a, 0x48, 0x52, 0xd2, 0xe0, 0xe2,
 	0x0a, 0x2e, 0xcd, 0x0d, 0x4a, 0x2d, 0x2c, 0x4d, 0x2d, 0x2e, 0x11, 0xe2, 0xe1, 0x62, 0x4c, 0x94,
@@ -208,8 +208,8 @@
 	0x00, 0x17, 0x73, 0x6a, 0x51, 0x11, 0x58, 0x25, 0x67, 0x10, 0x88, 0xa9, 0xa4, 0xcd, 0xc5, 0xeb,
 	0x9c, 0x9f, 0x97, 0x9c, 0x58, 0x82, 0x61, 0x30, 0x27, 0x8a, 0xc1, 0x9c, 0x20, 0x83, 0x75, 0xb9,
 	0xb8, 0x61, 0x8a, 0x51, 0xcc, 0xe6, 0xc4, 0x6a, 0xb6, 0x51, 0x0c, 0x17, 0xb3, 0x63, 0x4a, 0x8a,
-	0x90, 0x2a, 0x17, 0x33, 0xd0, 0x39, 0x42, 0x7c, 0x7a, 0x05, 0x49, 0x7a, 0x08, 0x1f, 0x48, 0xf1,
-	0xc0, 0xf9, 0x40, 0xb3, 0x94, 0x18, 0x84, 0xf4, 0xb8, 0xd8, 0x20, 0x86, 0x0b, 0x09, 0x82, 0x64,
-	0x50, 0x5c, 0x25, 0xc5, 0x8f, 0x2c, 0x04, 0x56, 0x9f, 0xc4, 0x06, 0x0e, 0x1a, 0x63, 0x40, 0x00,
-	0x00, 0x00, 0xff, 0xff, 0xdc, 0x37, 0x81, 0x99, 0x2a, 0x01, 0x00, 0x00,
-}
+	0x90, 0x2a, 0x17, 0x73, 0x70, 0x69, 0xae, 0x10, 0x9f, 0x5e, 0x41, 0x92, 0x1e, 0xc2, 0x07, 0x52,
+	0x3c, 0x70, 0x7e, 0x41, 0x4e, 0xa5, 0x12, 0x83, 0x90, 0x1e, 0x17, 0x1b, 0xc4, 0x70, 0x21, 0x41,
+	0x90, 0x0c, 0x8a, 0xab, 0xa4, 0xf8, 0x91, 0x85, 0xc0, 0xea, 0x93, 0xd8, 0xc0, 0x41, 0x63, 0x0c,
+	0x08, 0x00, 0x00, 0xff, 0xff, 0xdc, 0x37, 0x81, 0x99, 0x2a, 0x01, 0x00, 0x00,
+}