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agent/grpc-internal/balancer/custombalancer.go

@@ -11,9 +11,8 @@ func init() {
 	balancer.Register(newCustomPickfirstBuilder())
 }
 
-// CustomBalancerName is the name of the modified pick_first balancer.
-const CustomBalancerName = "pick_first_custom"
-
+// logger is referenced in pickfirst.go.
+// The gRPC library uses the same component name.
 var logger = grpclog.Component("balancer")
 
 func newCustomPickfirstBuilder() balancer.Builder {
@@ -29,9 +28,10 @@ func (*customPickfirstBuilder) Build(cc balancer.ClientConn, opt balancer.BuildO
 }
 
 func (*customPickfirstBuilder) Name() string {
-	return CustomBalancerName
+	return "pick_first_custom"
 }
 
+// customPickfirstBalancer overrides UpdateClientConnState of pickfirstBalancer.
 type customPickfirstBalancer struct {
 	pickfirstBalancer
 

agent/grpc-internal/balancer/pickfirst.go

@@ -1,4 +1,4 @@
-// NOTICE: This file is a derivative of grpc's pick_first implementation [1].
+// NOTICE: This file is a copy of grpc's pick_first implementation [1].
 // It is preserved as-is with the init() removed for easier updating.
 //
 // [1]: https://github.com/grpc/grpc-go/blob/v1.49.x/pickfirst.go