protoc plugin supports proto3 optional (#63)

Makefile

@@ -27,8 +27,9 @@ checkgofmt:
 
 .PHONY: generate
 generate:
-	@GO111MODULE=on go install ./cmd/protoc-gen-grpchan
-	@GO111MODULE=on go install github.com/golang/protobuf/protoc-gen-go
+	@go install ./cmd/protoc-gen-grpchan
+	@go install google.golang.org/protobuf/cmd/protoc-gen-go@a709e31e5d12
+	@go install google.golang.org/grpc/cmd/[email protected]
 	go generate ./...
 
 .PHONY: vet
@@ -37,17 +38,17 @@ vet:
 
 .PHONY: staticcheck
 staticcheck:
-	@GO111MODULE=on go install honnef.co/go/tools/cmd/staticcheck
+	@GO111MODULE=on go install honnef.co/go/tools/cmd/staticcheck@v0.0.1-2020.1.4
 	staticcheck ./...
 
 .PHONY: ineffassign
 ineffassign:
-	@GO111MODULE=on go install github.com/gordonklaus/ineffassign
+	@GO111MODULE=on go install github.com/gordonklaus/ineffassign@v0.0.0-20200309095847-7953dde2c7bf
 	ineffassign .
 
 .PHONY: predeclared
 predeclared:
-	@GO111MODULE=on go install github.com/nishanths/predeclared
+	@GO111MODULE=on go install github.com/nishanths/predeclared@v0.0.0-20200524104333-86fad755b4d3
 	predeclared .
 
 # Intentionally omitted from CI, but target here for ad-hoc reports.

cmd/protoc-gen-grpchan/protoc-gen-grpchan.go

@@ -13,13 +13,15 @@ import (
 	"github.com/jhump/gopoet"
 	"github.com/jhump/goprotoc/plugins"
 	"github.com/jhump/protoreflect/desc"
+	"google.golang.org/protobuf/types/pluginpb"
 )
 
 func main() {
 	plugins.PluginMain(doCodeGen)
 }
 
 func doCodeGen(req *plugins.CodeGenRequest, resp *plugins.CodeGenResponse) error {
+	resp.SupportsFeatures(pluginpb.CodeGeneratorResponse_FEATURE_PROTO3_OPTIONAL)
 	args, err := parseArgs(req.Args)
 	if err != nil {
 		return err

go.mod

@@ -3,16 +3,11 @@ module github.com/fullstorydev/grpchan
 go 1.13
 
 require (
-	github.com/golang/protobuf v1.4.2
-	github.com/gordonklaus/ineffassign v0.0.0-20200309095847-7953dde2c7bf // indirect
+	github.com/golang/protobuf v1.5.0
 	github.com/jhump/gopoet v0.1.0
-	github.com/jhump/goprotoc v0.4.0
-	github.com/jhump/protoreflect v1.5.0
-	github.com/nishanths/predeclared v0.0.0-20200524104333-86fad755b4d3 // indirect
-	golang.org/x/net v0.0.0-20200226121028-0de0cce0169b
+	github.com/jhump/goprotoc v0.5.0
+	github.com/jhump/protoreflect v1.11.0
 	google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013
-	google.golang.org/grpc v1.36.0
-	google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.1.0 // indirect
-	google.golang.org/protobuf v1.25.0
-	honnef.co/go/tools v0.0.1-2020.1.4 // indirect
+	google.golang.org/grpc v1.38.0
+	google.golang.org/protobuf v1.26.0
 )