grpc-gateway/generator: respect full package (grpc-ecosystem#462)

If you provide a go_package, your wishes will be reflected in the grpc-gateway output.

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

@@ -78,6 +78,9 @@ func (g *generator) Generate(targets []*descriptor.File) ([]*plugin.CodeGenerato
 			return nil, err
 		}
 		name := file.GetName()
+		if file.GoPkg.Path != "" {
+			name = fmt.Sprintf("%s/%s", file.GoPkg.Path, filepath.Base(name))
+		}
 		ext := filepath.Ext(name)
 		base := strings.TrimSuffix(name, ext)
 		output := fmt.Sprintf("%s.pb.gw.go", base)

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

@@ -1,6 +1,7 @@
 package gengateway
 
 import (
+	"path/filepath"
 	"strings"
 	"testing"
 
@@ -9,7 +10,16 @@ import (
 	"github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway/descriptor"
 )
 
-func TestGenerateServiceWithoutBindings(t *testing.T) {
+func newExampleFileDescriptor() *descriptor.File {
+	return newExampleFileDescriptorWithGoPkg(
+		&descriptor.GoPackage{
+			Path: "example.com/path/to/example/example.pb",
+			Name: "example_pb",
+		},
+	)
+}
+
+func newExampleFileDescriptorWithGoPkg(gp *descriptor.GoPackage) *descriptor.File {
 	msgdesc := &protodescriptor.DescriptorProto{
 		Name: proto.String("ExampleMessage"),
 	}
@@ -39,18 +49,15 @@ func TestGenerateServiceWithoutBindings(t *testing.T) {
 		Name:   proto.String("ExampleService"),
 		Method: []*protodescriptor.MethodDescriptorProto{meth, meth1},
 	}
-	file := descriptor.File{
+	return &descriptor.File{
 		FileDescriptorProto: &protodescriptor.FileDescriptorProto{
 			Name:        proto.String("example.proto"),
 			Package:     proto.String("example"),
 			Dependency:  []string{"a.example/b/c.proto", "a.example/d/e.proto"},
 			MessageType: []*protodescriptor.DescriptorProto{msgdesc},
 			Service:     []*protodescriptor.ServiceDescriptorProto{svc},
 		},
-		GoPkg: descriptor.GoPackage{
-			Path: "example.com/path/to/example/example.pb",
-			Name: "example_pb",
-		},
+		GoPkg:    *gp,
 		Messages: []*descriptor.Message{msg},
 		Services: []*descriptor.Service{
 			{
@@ -76,8 +83,12 @@ func TestGenerateServiceWithoutBindings(t *testing.T) {
 			},
 		},
 	}
+}
+
+func TestGenerateServiceWithoutBindings(t *testing.T) {
+	file := newExampleFileDescriptor()
 	g := &generator{}
-	got, err := g.generate(crossLinkFixture(&file))
+	got, err := g.generate(crossLinkFixture(file))
 	if err != nil {
 		t.Errorf("generate(%#v) failed with %v; want success", file, err)
 		return
@@ -86,3 +97,57 @@ func TestGenerateServiceWithoutBindings(t *testing.T) {
 		t.Errorf("generate(%#v) = %s; does not want to contain %s", file, got, notwanted)
 	}
 }
+
+func TestGenerateOutputPath(t *testing.T) {
+	cases := []struct {
+		file     *descriptor.File
+		expected string
+	}{
+		{
+			file: newExampleFileDescriptorWithGoPkg(
+				&descriptor.GoPackage{
+					Path: "example.com/path/to/example",
+					Name: "example_pb",
+				},
+			),
+			expected: "example.com/path/to/example",
+		},
+		{
+			file: newExampleFileDescriptorWithGoPkg(
+				&descriptor.GoPackage{
+					Path: "example",
+					Name: "example_pb",
+				},
+			),
+			expected: "example",
+		},
+	}
+
+	g := &generator{}
+	for _, c := range cases {
+		file := c.file
+		gots, err := g.Generate([]*descriptor.File{crossLinkFixture(file)})
+		if err != nil {
+			t.Errorf("Generate(%#v) failed with %v; wants success", file, err)
+			return
+		}
+
+		if len(gots) != 1 {
+			t.Errorf("Generate(%#v) failed; expects on result got %d", file, len(gots))
+			return
+		}
+
+		got := gots[0]
+		if got.Name == nil {
+			t.Errorf("Generate(%#v) failed; expects non-nil Name(%v)", file, got.Name)
+			return
+		}
+
+		gotPath := filepath.Dir(*got.Name)
+		expectedPath := c.expected
+		if gotPath != expectedPath {
+			t.Errorf("Generate(%#v) failed; got path: %s expected path: %s", file, gotPath, expectedPath)
+			return
+		}
+	}
+}