Allow *.orion.pb.go files to access the exported-service-desc from *.pb.go

protoc-gen-orion/orion.go

@@ -44,9 +44,10 @@ type commentsInfo struct {
 }
 
 type data struct {
-	FileName    string
-	PackageName string
-	Services    []*service
+	FileName      string
+	PackageName   string
+	GoPackagePath string
+	Services      []*service
 }
 
 type service struct {
@@ -96,13 +97,21 @@ type orionMiddleware struct {
 	Names      string
 }
 
+type ProtocParams struct {
+	StandaloneMode      bool
+	ExportedServiceDesc bool
+}
+
 var tmpl = `// Code generated by protoc-gen-orion. DO NOT EDIT.
 // source: {{ .FileName }}
 
 package {{ .PackageName }}
 {{ if .Services }}
 import (
 	orion "github.com/carousell/Orion/orion"
+	{{- if .GoPackagePath}}
+    {{ .PackageName }} "{{ .GoPackagePath }}"
+	{{- end }}
 )
 
 // If you see error please update your orion-protoc-gen by running 'go get -u github.com/carousell/Orion/protoc-gen-orion'
@@ -131,7 +140,7 @@ func Register{{.SvcName}}{{.MethodName}}Decoder(svr orion.Server, decoder orion.
 	orion.RegisterDecoder(svr, "{{.SvcName}}", "{{.MethodName}}", decoder)
 }
 {{ end }}
-//Streams
+// Streams
 {{ range .Streams }}
 // {{ . }}
 {{ end }}
@@ -199,14 +208,19 @@ func main() {
 		filesToGenerate[v] = true
 	}
 
+	reqParams, err := parseProtocParams(request.GetParameter())
+	if err != nil {
+		logError(err, "parse protoc params")
+	}
+
 	response := new(plugin.CodeGeneratorResponse)
 	response.File = make([]*plugin.CodeGeneratorResponse_File, 0)
 
 	for _, file := range request.GetProtoFile() {
 		if _, ok := filesToGenerate[file.GetName()]; ok {
 			// check if file has any service
 			if len(file.Service) > 0 {
-				f := generateFile(populate(file))
+				f := generateFile(populate(file, reqParams))
 				response.File = append(response.File, f)
 			}
 		}
@@ -242,24 +256,26 @@ func generateFile(d *data) *plugin.CodeGeneratorResponse_File {
 	return file
 }
 
-func populate(file *descriptor.FileDescriptorProto) *data {
+func populate(file *descriptor.FileDescriptorProto, params ProtocParams) *data {
 	d := new(data)
 	d.FileName = *file.Name
 	d.PackageName = strings.Replace(file.GetPackage(), ".", "_", 10)
-
+	if params.StandaloneMode {
+		d.GoPackagePath = parseGoPackage(file.GetOptions().GetGoPackage())
+	}
 	d.Services = make([]*service, 0)
-	generate(d, file)
+	generate(d, file, params)
 
 	return d
 }
 
-func generate(d *data, file *descriptor.FileDescriptorProto) {
+func generate(d *data, file *descriptor.FileDescriptorProto, params ProtocParams) {
 	comments := extractComments(file)
 	for index, svc := range file.GetService() {
 
 		origServName := svc.GetName()
 		servName := generator.CamelCase(origServName) // use the same logic from go-grpc generator
-		serviceDescVar := "_" + servName + "_serviceDesc"
+		serviceDescVar := getServiceDescVar(d.PackageName, servName, params.ExportedServiceDesc, params.StandaloneMode)
 
 		s := new(service)
 		s.Encoders = make([]*encoder, 0)
@@ -430,3 +446,58 @@ func extractComments(file *descriptor.FileDescriptorProto) map[string]*descripto
 	}
 	return comments
 }
+
+func parseProtocParams(reqParam string) (ProtocParams, error) {
+	pp := ProtocParams{}
+	for _, param := range strings.Split(reqParam, ",") {
+		var value string
+		if i := strings.Index(param, "="); i >= 0 {
+			value = param[i+1:]
+			param = param[0:i]
+		}
+		switch param {
+		case "standalone-mode":
+			boolValue, err := parseBoolValue(value)
+			if err != nil {
+				return ProtocParams{}, fmt.Errorf(`bad value for parameter %q: %w`, param, err)
+			}
+			pp.StandaloneMode = boolValue
+		case "exported-service-desc":
+			boolValue, err := parseBoolValue(value)
+			if err != nil {
+				return ProtocParams{}, fmt.Errorf(`bad value for parameter %q: %w`, param, err)
+			}
+			pp.ExportedServiceDesc = boolValue
+		}
+	}
+	return pp, nil
+}
+
+func parseBoolValue(value string) (bool, error) {
+	switch value {
+	case "true":
+		return true, nil
+	case "false":
+		return false, nil
+	default:
+		return false, fmt.Errorf(`want "true" or "false"`)
+	}
+}
+
+func getServiceDescVar(packageName string, serviceName string, exportedServiceDesc bool, standAlone bool) string {
+	if standAlone {
+		return packageName + "." + serviceName + "_ServiceDesc"
+	}
+	if exportedServiceDesc {
+		return serviceName + "_ServiceDesc"
+	}
+	return "_" + serviceName + "_serviceDesc"
+}
+
+func parseGoPackage(goPackage string) string {
+	parts := strings.Split(goPackage, ";")
+	if len(parts) == 0 {
+		return ""
+	}
+	return parts[0]
+}

protoc-gen-orion/testprotos/Makefile

@@ -0,0 +1,15 @@
+# Generate the *.orion.pb.go into each folder.
+# The generated files shouldn't be changed, unless you change the orion template format.
+# Notice: Before running the script, you should install the testing binary of protoc-gen-orion in your device.
+all:
+# The default protoc-gen-orion will provide the unexported-service-desc.
+# It's suitable for protoc-gen-go version lower and equal than v1.5.2
+	protoc --orion_out="." example/example.proto
+
+# For protoc-gen-go version higher and equal than v1.20.0, please enable the exported-service-desc option.
+	protoc --orion_out="exported-service-desc=true:." exported_service_desc/example.proto
+
+# Enable the standalone-mode option will allow your to place *.orion.pb.go and *.pb.go into different folder.
+# The *.orion.pb.go imports the *.pb.go by go_package defined in *.proto.
+	protoc --orion_out="standalone-mode=true:." standalone_mode/example.proto
+	mv standalone_mode/example.proto.orion.pb.go standalone_mode/orion/

protoc-gen-orion/testprotos/example/example.go

@@ -0,0 +1,5 @@
+package example
+
+import "google.golang.org/grpc"
+
+var _ExampleService_serviceDesc grpc.ServiceDesc

protoc-gen-orion/testprotos/example/example.proto

@@ -0,0 +1,37 @@
+syntax = "proto3";
+
+package example;
+
+option go_package = "github.com/carousell/Orion/protoc-gen-orion/testprotos/example;example";
+
+service ExampleService {
+  // Normal endpoint
+  rpc NormalGet(GetRequest) returns (GetResponse);
+
+  // HTTP endpoint
+  // ORION:URL: GET /example
+  rpc HttpGet(GetRequest) returns (GetResponse);
+
+  // HTTP endpoint with middleware
+  // ORION:URL: GET /auth/example
+  // ORION:MIDDLEWRE: auth
+  rpc AuthGet(GetRequest) returns (GetResponse);
+
+  // HTTP endpoint with middleware
+  // ORION:URL: GET /option/example
+  // ORION:OPTION: IGNORE_NR
+  rpc OptionGet(GetRequest) returns (GetResponse);
+
+  // HTTP endpoint with options
+  // ORION:URL: GET /auth/option/example
+  // ORION:MIDDLEWRE: auth
+  // ORION:OPTION: IGNORE_NR
+  rpc AuthOptionGet(GetRequest) returns (GetResponse);
+
+  // ORION:URL: GET /stream/example
+  rpc StreamGet(stream GetRequest) returns (stream GetResponse);
+}
+
+message GetRequest {}
+
+message GetResponse {}

protoc-gen-orion/testprotos/exported_service_desc/example.go

@@ -0,0 +1,5 @@
+package example
+
+import "google.golang.org/grpc"
+
+var ExampleService_ServiceDesc grpc.ServiceDesc

protoc-gen-orion/testprotos/exported_service_desc/example.proto

@@ -0,0 +1,14 @@
+syntax = "proto3";
+
+package example;
+
+option go_package = "github.com/carousell/Orion/protoc-gen-orion/testprotos/exported_service_desc;example";
+
+service ExampleService {
+  // Normal endpoint
+  rpc NormalGet(GetRequest) returns (GetResponse);
+}
+
+message GetRequest {}
+
+message GetResponse {}