WIP: grpc gen changes

Author: ebroberson

protoc-gen-go-bbs/bbs.go

@@ -27,17 +27,31 @@ type bbsGenerateHelperInterface interface {
 }
 type bbsGenerateHelper struct{}
 
+var ignoredMessages []string = []string{"ProtoRoutes"}
+var ignoredEnums []string = []string{}
+var ignoredServices []string = []string{}
+
 var helper bbsGenerateHelperInterface = bbsGenerateHelper{}
 
 func getUnsafeName(g *protogen.GeneratedFile, ident protogen.GoIdent) string {
 	return g.QualifiedGoIdent(ident)
 }
 
+func getUnsafeNameFromString(name string) string {
+	unsafeName := name
+	return unsafeName
+}
+
 func getCopysafeName(g *protogen.GeneratedFile, ident protogen.GoIdent) (string, bool) {
 	unsafeName := getUnsafeName(g, ident)
 	return strings.CutPrefix(unsafeName, *prefix)
 }
 
+func getCopysafeNameFromString(name string) (string, bool) {
+	unsafeName := getUnsafeNameFromString(name)
+	return strings.CutPrefix(unsafeName, *prefix)
+}
+
 func getFieldName(goName string) string {
 	result := goName
 	return result
@@ -694,6 +708,27 @@ func generateFile(plugin *protogen.Plugin, file *protogen.File) *protogen.Genera
 	return g
 }
 
+func generateRpcFile(plugin *protogen.Plugin, file *protogen.File) *protogen.GeneratedFile {
+	filename := file.GeneratedFilenamePrefix + "_bbs_grpc.pb.go"
+	g := plugin.NewGeneratedFile(filename, file.GoImportPath)
+	g.P("// Code generated by protoc-gen-go-bbs. DO NOT EDIT.")
+	g.P("// versions:")
+	g.P("// - protoc-gen-go-bbs v", version) // version from main.go
+	g.P("// - protoc-gen-go-grpc ", "TODO: get version")
+	g.P("// - protoc            ", protocVersion(plugin))
+
+	if file.Proto.GetOptions().GetDeprecated() {
+		g.P("// ", file.Desc.Path(), " is a deprecated file.")
+	} else {
+		g.P("// source: ", file.Desc.Path())
+	}
+	g.P()
+	g.P("package ", file.GoPackageName)
+	g.P()
+	generateRpcFileContent(file, g)
+	return g
+}
+
 func protocVersion(plugin *protogen.Plugin) string {
 	v := plugin.Request.GetCompilerVersion()
 	if v == nil {
@@ -706,10 +741,7 @@ func protocVersion(plugin *protogen.Plugin) string {
 	return fmt.Sprintf("v%d.%d.%d%s", v.GetMajor(), v.GetMinor(), v.GetPatch(), suffix)
 }
 
-var ignoredMessages []string = []string{"ProtoRoutes"}
-var ignoredEnums []string = []string{}
-
-func generateFileContent(file *protogen.File, g *protogen.GeneratedFile) {
+func generateFileEnums(file *protogen.File, g *protogen.GeneratedFile) {
 	for _, eNuM := range file.Enums {
 		if *debug {
 			log.Printf("New Enum Detected: %+v\n\n", eNuM)
@@ -722,7 +754,9 @@ func generateFileContent(file *protogen.File, g *protogen.GeneratedFile) {
 
 		helper.genGlobalEnum(g, eNuM)
 	}
+}
 
+func generateFileMessages(file *protogen.File, g *protogen.GeneratedFile) {
 	for _, msg := range file.Messages {
 		if *debug {
 			log.Printf("New Message Detected: %+v\n\n", msg)
@@ -740,3 +774,196 @@ func generateFileContent(file *protogen.File, g *protogen.GeneratedFile) {
 		helper.genFromProtoSliceMethod(g, msg)
 	}
 }
+
+func generateFileServices(file *protogen.File, g *protogen.GeneratedFile) {
+	for _, svc := range file.Services {
+		if *debug {
+			log.Printf("New Service Detected: %+v\n\n", svc)
+		}
+
+		//if slices.Contains(ignoredMessages, getUnsafeName(g, svc.GoIdent)) {
+		if slices.Contains(ignoredMessages, svc.GoName) {
+			log.Printf("\tIgnoring message %s", svc.Desc.Name())
+			continue
+		}
+
+		genImports(g)
+		genClient(g, svc)
+		genServer(g, svc)
+		genServiceDesc(file, g, svc)
+	}
+}
+
+func genImports(g *protogen.GeneratedFile) {
+	importBuilder := new(strings.Builder)
+	importT, err := template.New("import").Parse(
+		`
+import (
+	context "context"
+	grpc "google.golang.org/grpc"
+	codes "google.golang.org/grpc/codes"
+	status "google.golang.org/grpc/status"
+)
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+// Requires gRPC-Go v1.64.0 or later.
+const _ = grpc.SupportPackageIsVersion9
+`)
+	if err != nil {
+		panic(err)
+	}
+	importT.Execute(importBuilder, nil)
+	g.P(importBuilder.String())
+
+}
+
+func genClient(g *protogen.GeneratedFile, svc *protogen.Service) {
+
+	clientT, err := template.New("client").Parse(
+		`
+	type {{.ServiceName}}Client interface {
+		{{.ClientInterfaceMethods}} // build these
+	}
+
+	type {{.ServiceName | LowerFirst}} struct { // pass funcmap to get LowerFirst
+		cc grpc.ClientConnInterface
+	}
+
+	func New{{.ServiceName}}Client(cc grpc.ClientConnInterface) {{.ServiceName}}Client {
+		return &{{.ServiceName | LowerFirst}}Client{cc}
+	}
+
+	{{.ClientMethods}}
+	`)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func genServer(g *protogen.GeneratedFile, svc *protogen.Service) {
+	serverBuilder := new(strings.Builder)
+	serverT, err := template.New("server").Parse(
+		`
+	type {{.ServiceName}}Server interface {
+		{{.ServerInterfaceMethods}} // build these
+		mustEmbedUnimplemented{{.ServiceName}}Server()
+	}
+
+	// Unimplemented{{.ServiceName}Server must be embedded to have
+	// forward compatible implementations.
+	//
+	// NOTE: this should be embedded by value instead of pointer to avoid a nil
+	// pointer dereference when methods are called.
+	type Unimplemented{{.ServiceName}}Server struct {}
+
+	{{.UnimplementedServerMethods}} // build these
+	func (Unimplemented{{.ServiceName}}Server) mustEmbedUnimplemented{{.ServiceName}}Server() {}
+	func (Unimplemented{{.ServiceName}}Server) testEmbeddedByValue() {}
+
+	// Unsafe{{.ServiceName}}Server may be embedded to opt out of forward compatibility for this service.
+	// Use of this interface is not recommended, as added methods to {{.ServiceName}}Server will
+	// result in compilation errors.
+
+	func Register{{.ServiceName}}Server(s grpc.ServiceRegistrar, srv LocketServer) {
+		// If the following call panics, it indicates Unimplemented{{.ServiceName}}Server was
+		// embedded by pointer and is nil.  This will cause panics if an
+		// unimplemented method is ever invoked, so we test this at initialization
+		// time to prevent it from happening at runtime later due to I/O.
+		if t, ok := srv.(interface{ testEmbeddedByValue() }); ok {
+			t.testEmbeddedByValue()
+		}
+		s.RegisterService(&{{.ServiceName}}_ServiceDesc, srv)
+	}
+
+	{{.ServerMethods}}
+	`)
+	if err != nil {
+		panic(err)
+	}
+
+	serverT.Execute(serverBuilder, nil)
+}
+
+type Service struct {
+	Name   string
+	Source string
+}
+
+type ServiceDescData struct {
+	ServiceName    string
+	Methods        string
+	SourceFilename string
+}
+
+type MethodData struct {
+	ServiceName string
+	MethodName  string
+}
+
+func genServiceDesc(file *protogen.File, g *protogen.GeneratedFile, svc *protogen.Service) {
+	sourceFilename := file.Desc.Path()
+
+	if serviceName, ok := getCopysafeNameFromString(svc.GoName); ok {
+		methodsBuilder := new(strings.Builder)
+		methodT, err := template.New("method").Parse(
+			`
+		{
+			MethodName: "{{.MethodName}}",
+			Handler:    _{{.ServiceName}}_{{.MethodName}}_Handler,
+		}`)
+		if err != nil {
+			panic(err)
+		}
+
+		methodsBuilder.WriteString("Methods: []grpc.MethodDesc{")
+		for i, method := range svc.Methods {
+			methodName, _ := getCopysafeNameFromString(method.GoName)
+			methodT.Execute(methodsBuilder,
+				MethodData{
+					ServiceName: serviceName,
+					MethodName:  methodName,
+				})
+			if i < len(svc.Methods)-1 {
+				methodsBuilder.WriteRune(',')
+			}
+		}
+		methodsBuilder.WriteString("}")
+		methods := methodsBuilder.String()
+
+		serviceDescBuilder := new(strings.Builder)
+		serviceDescT, err := template.New("serviceDesc").Parse(
+			`
+// {{.ServiceName}}_ServiceDesc is the grpc.ServiceDesc for {{.ServiceName}} service.
+// It's only intended for direct use with grpc.RegisterService,
+// and not to be introspected or modified (even as a copy)
+var {{.ServiceName}}_ServiceDesc = grpc.ServiceDesc{
+	ServiceName: "models.{{.ServiceName}}",
+	HandlerType: (*{{.ServiceName}}Server)(nil),
+	{{.Methods}},
+	Streams:  []grpc.StreamDesc{},
+	Metadata: "{{.SourceFilename}}",
+}
+			`)
+		if err != nil {
+			panic(err)
+		}
+		serviceDescT.Execute(serviceDescBuilder,
+			ServiceDescData{
+				ServiceName:    serviceName,
+				Methods:        methods,
+				SourceFilename: sourceFilename,
+			})
+		g.P(serviceDescBuilder.String())
+
+	}
+}
+
+func generateFileContent(file *protogen.File, g *protogen.GeneratedFile) {
+	generateFileEnums(file, g)
+	generateFileMessages(file, g)
+}
+
+func generateRpcFileContent(file *protogen.File, g *protogen.GeneratedFile) {
+	generateFileServices(file, g)
+}

protoc-gen-go-bbs/main.go

@@ -42,6 +42,10 @@ func main() {
 			log.Printf("Generating %s\n", file.Desc.Path())
 
 			generateFile(plugin, file)
+			if len(file.Services) > 0 {
+				generateRpcFile(plugin, file)
+			}
+
 		}
 		return nil
 	})