support proto3 optional

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

.gitignore

@@ -0,0 +1,38 @@
+# Develop tools
+/.vscode/
+/.idea/
+
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Folders
+_obj
+_test
+_build
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+# Test binary, build with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# vim temp files
+*~
+*.swp
+*.swo
+/protoc-gen-micro
+

main.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"google.golang.org/protobuf/compiler/protogen"
+	"google.golang.org/protobuf/types/pluginpb"
 )
 
 var (
@@ -36,6 +37,7 @@ func (g *Generator) Generate(plugin *protogen.Plugin) error {
 	g.standalone = *flagStandalone
 	g.debug = *flagDebug
 	g.components = *flagComponents
+	plugin.SupportedFeatures = uint64(pluginpb.CodeGeneratorResponse_FEATURE_PROTO3_OPTIONAL)
 
 	// Protoc passes a slice of File structs for us to process
 	for _, component := range strings.Split(g.components, "|") {