feat: add Opaque API and Protobuf Editions support

internal/codegenerator/supported_features.go

@@ -2,23 +2,33 @@ package codegenerator
 
 import (
 	"google.golang.org/protobuf/compiler/protogen"
+	"google.golang.org/protobuf/types/descriptorpb"
 	"google.golang.org/protobuf/types/pluginpb"
 )
 
 func supportedCodeGeneratorFeatures() uint64 {
-	// Enable support for optional keyword in proto3.
-	return uint64(pluginpb.CodeGeneratorResponse_FEATURE_PROTO3_OPTIONAL)
+	// Enable support for Protobuf Editions
+	return uint64(pluginpb.CodeGeneratorResponse_FEATURE_PROTO3_OPTIONAL | pluginpb.CodeGeneratorResponse_FEATURE_SUPPORTS_EDITIONS)
+}
+
+func supportedEditions() (descriptorpb.Edition, descriptorpb.Edition) {
+	// Declare support for edition 2023 only
+	return descriptorpb.Edition_EDITION_2023, descriptorpb.Edition_EDITION_2023
 }
 
 // SetSupportedFeaturesOnPluginGen sets supported proto3 features
 // on protogen.Plugin.
 func SetSupportedFeaturesOnPluginGen(gen *protogen.Plugin) {
 	gen.SupportedFeatures = supportedCodeGeneratorFeatures()
+	gen.SupportedEditionsMinimum, gen.SupportedEditionsMaximum = supportedEditions()
 }
 
 // SetSupportedFeaturesOnCodeGeneratorResponse sets supported proto3 features
 // on pluginpb.CodeGeneratorResponse.
 func SetSupportedFeaturesOnCodeGeneratorResponse(resp *pluginpb.CodeGeneratorResponse) {
 	sf := supportedCodeGeneratorFeatures()
 	resp.SupportedFeatures = &sf
+	minE, maxE := supportedEditions()
+	minEN, maxEN := int32(minE.Number()), int32(maxE.Number())
+	resp.MinimumEdition, resp.MaximumEdition = &minEN, &maxEN
 }

protoc-gen-grpc-gateway/internal/gengateway/generator.go

@@ -6,11 +6,12 @@ import (
 	"go/format"
 	"path"
 
-	"github.com/grpc-ecosystem/grpc-gateway/v2/internal/descriptor"
-	gen "github.com/grpc-ecosystem/grpc-gateway/v2/internal/generator"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/protobuf/proto"
 	"google.golang.org/protobuf/types/pluginpb"
+
+	"github.com/grpc-ecosystem/grpc-gateway/v2/internal/descriptor"
+	gen "github.com/grpc-ecosystem/grpc-gateway/v2/internal/generator"
 )
 
 var errNoTargetService = errors.New("no target service defined in the file")
@@ -22,11 +23,12 @@ type generator struct {
 	registerFuncSuffix string
 	allowPatchFeature  bool
 	standalone         bool
+	useOpaqueAPI       bool
 }
 
 // New returns a new generator which generates grpc gateway files.
 func New(reg *descriptor.Registry, useRequestContext bool, registerFuncSuffix string,
-	allowPatchFeature, standalone bool) gen.Generator {
+	allowPatchFeature, standalone bool, useOpaqueAPI bool) gen.Generator {
 	var imports []descriptor.GoPackage
 	for _, pkgpath := range []string{
 		"context",
@@ -66,6 +68,7 @@ func New(reg *descriptor.Registry, useRequestContext bool, registerFuncSuffix st
 		registerFuncSuffix: registerFuncSuffix,
 		allowPatchFeature:  allowPatchFeature,
 		standalone:         standalone,
+		useOpaqueAPI:       useOpaqueAPI,
 	}
 }
 
@@ -132,6 +135,7 @@ func (g *generator) generate(file *descriptor.File) (string, error) {
 		UseRequestContext:  g.useRequestContext,
 		RegisterFuncSuffix: g.registerFuncSuffix,
 		AllowPatchFeature:  g.allowPatchFeature,
+		UseOpaqueAPI:       g.useOpaqueAPI,
 	}
 	if g.reg != nil {
 		params.OmitPackageDoc = g.reg.GetOmitPackageDoc()

protoc-gen-grpc-gateway/internal/gengateway/generator_test.go

@@ -3,9 +3,10 @@ package gengateway
 import (
 	"testing"
 
-	"github.com/grpc-ecosystem/grpc-gateway/v2/internal/descriptor"
 	"google.golang.org/protobuf/proto"
 	"google.golang.org/protobuf/types/descriptorpb"
+
+	"github.com/grpc-ecosystem/grpc-gateway/v2/internal/descriptor"
 )
 
 func newExampleFileDescriptorWithGoPkg(gp *descriptor.GoPackage, filenamePrefix string) *descriptor.File {
@@ -76,8 +77,22 @@ func newExampleFileDescriptorWithGoPkg(gp *descriptor.GoPackage, filenamePrefix
 }
 
 func TestGenerator_Generate(t *testing.T) {
+
+	// Test with Open Struct API (default)
+	t.Run("OpenStructAPI", func(t *testing.T) {
+		testGeneratorGenerate(t, false)
+	})
+
+	// Test with Opaque API
+	t.Run("OpaqueAPI", func(t *testing.T) {
+		testGeneratorGenerate(t, true)
+	})
+}
+
+func testGeneratorGenerate(t *testing.T, useOpaqueAPI bool) {
 	g := new(generator)
 	g.reg = descriptor.NewRegistry()
+	g.useOpaqueAPI = useOpaqueAPI
 	result, err := g.Generate([]*descriptor.File{
 		crossLinkFixture(newExampleFileDescriptorWithGoPkg(&descriptor.GoPackage{
 			Path: "example.com/path/to/example",