Example of using grpcui standalone package

foo.pb.go

// Code generated by protoc-gen-go. DO NOT EDIT.
// versions:
// 	protoc-gen-go v1.24.0-devel
// 	protoc        v3.11.3
// source: foo.proto

package main

import (
	context "context"
	proto "github.com/golang/protobuf/proto"
	empty "github.com/golang/protobuf/ptypes/empty"
	grpc "google.golang.org/grpc"
	codes "google.golang.org/grpc/codes"
	status "google.golang.org/grpc/status"
	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
	reflect "reflect"
)

const (
	// Verify that this generated code is sufficiently up-to-date.
	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
	// Verify that runtime/protoimpl is sufficiently up-to-date.
	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
)

// This is a compile-time assertion that a sufficiently up-to-date version
// of the legacy proto package is being used.
const _ = proto.ProtoPackageIsVersion4

var File_foo_proto protoreflect.FileDescriptor

var file_foo_proto_rawDesc = []byte{
	0x0a, 0x09, 0x66, 0x6f, 0x6f, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x04, 0x6d, 0x61, 0x69,
	0x6e, 0x1a, 0x1b, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62,
	0x75, 0x66, 0x2f, 0x65, 0x6d, 0x70, 0x74, 0x79, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x32, 0x3c,
	0x0a, 0x03, 0x46, 0x6f, 0x6f, 0x12, 0x35, 0x0a, 0x03, 0x46, 0x6f, 0x6f, 0x12, 0x16, 0x2e, 0x67,
	0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x45,
	0x6d, 0x70, 0x74, 0x79, 0x1a, 0x16, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72,
	0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x45, 0x6d, 0x70, 0x74, 0x79, 0x32, 0x3c, 0x0a, 0x03,
	0x42, 0x61, 0x72, 0x12, 0x35, 0x0a, 0x03, 0x42, 0x61, 0x72, 0x12, 0x16, 0x2e, 0x67, 0x6f, 0x6f,
	0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x45, 0x6d, 0x70,
	0x74, 0x79, 0x1a, 0x16, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74,
	0x6f, 0x62, 0x75, 0x66, 0x2e, 0x45, 0x6d, 0x70, 0x74, 0x79, 0x32, 0x3c, 0x0a, 0x03, 0x42, 0x61,
	0x7a, 0x12, 0x35, 0x0a, 0x03, 0x42, 0x61, 0x7a, 0x12, 0x16, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c,
	0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x45, 0x6d, 0x70, 0x74, 0x79,
	0x1a, 0x16, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62,
	0x75, 0x66, 0x2e, 0x45, 0x6d, 0x70, 0x74, 0x79, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
}

var file_foo_proto_goTypes = []interface{}{
	(*empty.Empty)(nil), // 0: google.protobuf.Empty
}
var file_foo_proto_depIdxs = []int32{
	0, // 0: main.Foo.Foo:input_type -> google.protobuf.Empty
	0, // 1: main.Bar.Bar:input_type -> google.protobuf.Empty
	0, // 2: main.Baz.Baz:input_type -> google.protobuf.Empty
	0, // 3: main.Foo.Foo:output_type -> google.protobuf.Empty
	0, // 4: main.Bar.Bar:output_type -> google.protobuf.Empty
	0, // 5: main.Baz.Baz:output_type -> google.protobuf.Empty
	3, // [3:6] is the sub-list for method output_type
	0, // [0:3] is the sub-list for method input_type
	0, // [0:0] is the sub-list for extension type_name
	0, // [0:0] is the sub-list for extension extendee
	0, // [0:0] is the sub-list for field type_name
}

func init() { file_foo_proto_init() }
func file_foo_proto_init() {
	if File_foo_proto != nil {
		return
	}
	type x struct{}
	out := protoimpl.TypeBuilder{
		File: protoimpl.DescBuilder{
			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
			RawDescriptor: file_foo_proto_rawDesc,
			NumEnums:      0,
			NumMessages:   0,
			NumExtensions: 0,
			NumServices:   3,
		},
		GoTypes:           file_foo_proto_goTypes,
		DependencyIndexes: file_foo_proto_depIdxs,
	}.Build()
	File_foo_proto = out.File
	file_foo_proto_rawDesc = nil
	file_foo_proto_goTypes = nil
	file_foo_proto_depIdxs = nil
}

// Reference imports to suppress errors if they are not otherwise used.
var _ context.Context
var _ grpc.ClientConnInterface

// This is a compile-time assertion to ensure that this generated file
// is compatible with the grpc package it is being compiled against.
const _ = grpc.SupportPackageIsVersion6

// FooClient is the client API for Foo service.
//
// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
type FooClient interface {
	Foo(ctx context.Context, in *empty.Empty, opts ...grpc.CallOption) (*empty.Empty, error)
}

type fooClient struct {
	cc grpc.ClientConnInterface
}

func NewFooClient(cc grpc.ClientConnInterface) FooClient {
	return &fooClient{cc}
}

func (c *fooClient) Foo(ctx context.Context, in *empty.Empty, opts ...grpc.CallOption) (*empty.Empty, error) {
	out := new(empty.Empty)
	err := c.cc.Invoke(ctx, "/main.Foo/Foo", in, out, opts...)
	if err != nil {
		return nil, err
	}
	return out, nil
}

// FooServer is the server API for Foo service.
type FooServer interface {
	Foo(context.Context, *empty.Empty) (*empty.Empty, error)
}

// UnimplementedFooServer can be embedded to have forward compatible implementations.
type UnimplementedFooServer struct {
}

func (*UnimplementedFooServer) Foo(context.Context, *empty.Empty) (*empty.Empty, error) {
	return nil, status.Errorf(codes.Unimplemented, "method Foo not implemented")
}

func RegisterFooServer(s *grpc.Server, srv FooServer) {
	s.RegisterService(&_Foo_serviceDesc, srv)
}

func _Foo_Foo_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
	in := new(empty.Empty)
	if err := dec(in); err != nil {
		return nil, err
	}
	if interceptor == nil {
		return srv.(FooServer).Foo(ctx, in)
	}
	info := &grpc.UnaryServerInfo{
		Server:     srv,
		FullMethod: "/main.Foo/Foo",
	}
	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
		return srv.(FooServer).Foo(ctx, req.(*empty.Empty))
	}
	return interceptor(ctx, in, info, handler)
}

var _Foo_serviceDesc = grpc.ServiceDesc{
	ServiceName: "main.Foo",
	HandlerType: (*FooServer)(nil),
	Methods: []grpc.MethodDesc{
		{
			MethodName: "Foo",
			Handler:    _Foo_Foo_Handler,
		},
	},
	Streams:  []grpc.StreamDesc{},
	Metadata: "foo.proto",
}

// BarClient is the client API for Bar service.
//
// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
type BarClient interface {
	Bar(ctx context.Context, in *empty.Empty, opts ...grpc.CallOption) (*empty.Empty, error)
}

type barClient struct {
	cc grpc.ClientConnInterface
}

func NewBarClient(cc grpc.ClientConnInterface) BarClient {
	return &barClient{cc}
}

func (c *barClient) Bar(ctx context.Context, in *empty.Empty, opts ...grpc.CallOption) (*empty.Empty, error) {
	out := new(empty.Empty)
	err := c.cc.Invoke(ctx, "/main.Bar/Bar", in, out, opts...)
	if err != nil {
		return nil, err
	}
	return out, nil
}

// BarServer is the server API for Bar service.
type BarServer interface {
	Bar(context.Context, *empty.Empty) (*empty.Empty, error)
}

// UnimplementedBarServer can be embedded to have forward compatible implementations.
type UnimplementedBarServer struct {
}

func (*UnimplementedBarServer) Bar(context.Context, *empty.Empty) (*empty.Empty, error) {
	return nil, status.Errorf(codes.Unimplemented, "method Bar not implemented")
}

func RegisterBarServer(s *grpc.Server, srv BarServer) {
	s.RegisterService(&_Bar_serviceDesc, srv)
}

func _Bar_Bar_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
	in := new(empty.Empty)
	if err := dec(in); err != nil {
		return nil, err
	}
	if interceptor == nil {
		return srv.(BarServer).Bar(ctx, in)
	}
	info := &grpc.UnaryServerInfo{
		Server:     srv,
		FullMethod: "/main.Bar/Bar",
	}
	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
		return srv.(BarServer).Bar(ctx, req.(*empty.Empty))
	}
	return interceptor(ctx, in, info, handler)
}

var _Bar_serviceDesc = grpc.ServiceDesc{
	ServiceName: "main.Bar",
	HandlerType: (*BarServer)(nil),
	Methods: []grpc.MethodDesc{
		{
			MethodName: "Bar",
			Handler:    _Bar_Bar_Handler,
		},
	},
	Streams:  []grpc.StreamDesc{},
	Metadata: "foo.proto",
}

// BazClient is the client API for Baz service.
//
// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
type BazClient interface {
	Baz(ctx context.Context, in *empty.Empty, opts ...grpc.CallOption) (*empty.Empty, error)
}

type bazClient struct {
	cc grpc.ClientConnInterface
}

func NewBazClient(cc grpc.ClientConnInterface) BazClient {
	return &bazClient{cc}
}

func (c *bazClient) Baz(ctx context.Context, in *empty.Empty, opts ...grpc.CallOption) (*empty.Empty, error) {
	out := new(empty.Empty)
	err := c.cc.Invoke(ctx, "/main.Baz/Baz", in, out, opts...)
	if err != nil {
		return nil, err
	}
	return out, nil
}

// BazServer is the server API for Baz service.
type BazServer interface {
	Baz(context.Context, *empty.Empty) (*empty.Empty, error)
}

// UnimplementedBazServer can be embedded to have forward compatible implementations.
type UnimplementedBazServer struct {
}

func (*UnimplementedBazServer) Baz(context.Context, *empty.Empty) (*empty.Empty, error) {
	return nil, status.Errorf(codes.Unimplemented, "method Baz not implemented")
}

func RegisterBazServer(s *grpc.Server, srv BazServer) {
	s.RegisterService(&_Baz_serviceDesc, srv)
}

func _Baz_Baz_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
	in := new(empty.Empty)
	if err := dec(in); err != nil {
		return nil, err
	}
	if interceptor == nil {
		return srv.(BazServer).Baz(ctx, in)
	}
	info := &grpc.UnaryServerInfo{
		Server:     srv,
		FullMethod: "/main.Baz/Baz",
	}
	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
		return srv.(BazServer).Baz(ctx, req.(*empty.Empty))
	}
	return interceptor(ctx, in, info, handler)
}

var _Baz_serviceDesc = grpc.ServiceDesc{
	ServiceName: "main.Baz",
	HandlerType: (*BazServer)(nil),
	Methods: []grpc.MethodDesc{
		{
			MethodName: "Baz",
			Handler:    _Baz_Baz_Handler,
		},
	},
	Streams:  []grpc.StreamDesc{},
	Metadata: "foo.proto",
}

foo.proto

syntax = "proto3";

package main;

import "google/protobuf/empty.proto";

service Foo {
    rpc Foo(google.protobuf.Empty) returns (google.protobuf.Empty);
}
service Bar {
    rpc Bar(google.protobuf.Empty) returns (google.protobuf.Empty);
}
service Baz {
    rpc Baz(google.protobuf.Empty) returns (google.protobuf.Empty);
}

gen.go

package main

//go:generate protoc --go_out=plugins=grpc:./ foo.proto

main.go

package main

import (
	"context"
	"flag"
	"fmt"
	"net"
	"net/http"
	"os"
	"path/filepath"

	"github.com/fullstorydev/grpcui/standalone"
	"github.com/golang/protobuf/ptypes/empty"
	"google.golang.org/grpc"
	"google.golang.org/grpc/reflection"
)

var grpcPort, httpPort int

func main() {
	flag.IntVar(&grpcPort, "grpc-port", 1234, "port on which grpc server will listen")
	flag.IntVar(&httpPort, "http-port", 1235, "port on which http server will listen")
	flag.Parse()

	run(context.Background())
}

func run(ctx context.Context) {

	//----------------------------
	// Start up our gRPC server
	//----------------------------
	fmt.Printf("Starting gRPC server on port %d...\n", grpcPort)
	svr := grpc.NewServer()

	// register some gRPC services
	RegisterFooServer(svr, newFooImpl())
	RegisterBarServer(svr, newBarImpl())
	RegisterBazServer(svr, newBazImpl())
	// also need the reflection service!
	reflection.Register(svr)

	l, err := net.Listen("tcp", fmt.Sprintf(":%d", grpcPort))
	if err != nil {
		exitWithError("failed to open listen socket on port %d: %v", grpcPort, err)
	}
	go func() {
		err := svr.Serve(l)
		if err != nil {
			exitWithError("failed to serve gRPC: %v", err)
		}
	}()

	//----------------------------
	// Create a client
	//----------------------------
	cc, err := grpc.Dial(fmt.Sprintf("127.0.0.1:%d", grpcPort), grpc.WithInsecure())
	if err != nil {
		exitWithError("failed to create client to local server: %v", err)
	}

	//----------------------------
	// Create gRPCui handler
	//----------------------------
	target := fmt.Sprintf("%s:%d", filepath.Base(os.Args[0]), grpcPort)
	// This is all there is to it!
	h, err := standalone.HandlerViaReflection(ctx, cc, target)
	if err != nil {
		exitWithError("failed to create client to local server: %v", err)
	}

	//----------------------------
	// Start up HTTP server
	//----------------------------
	fmt.Printf("Starting HTTP server on port %d...\n", httpPort)
	
	serveMux := http.NewServeMux()

	// register the grpcui
	serveMux.Handle("/grpcui/", http.StripPrefix("/grpcui", h))

	// register other handlers...
	serveMux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("content-type", "html")
		_, _ = fmt.Fprintf(w, `
			<html>
			<head><title>Example server</title></head>
			<body>
			<h1>Hello, world!</h1>
			<p>Check out the gRPC UI <a href="/grpcui/">here</a>.</p>
			</body>
			</html>
		`)
	})

	l, err = net.Listen("tcp", fmt.Sprintf(":%d", httpPort))
	if err != nil {
		exitWithError("failed to open listen socket on port %d: %v", httpPort, err)
	}

	err = http.Serve(l, serveMux)
	if err != nil {
		exitWithError("failed to serve HTTP: %v", err)
	}
}

func exitWithError(msgFormat string, args ...interface{}) {
	_, _ = fmt.Fprintf(os.Stderr, msgFormat, args...)
	_, _ = fmt.Fprintln(os.Stderr)
	os.Exit(1)
}

func newFooImpl() FooServer {
	return impl{}
}
func newBarImpl() BarServer {
	return impl{}
}
func newBazImpl() BazServer {
	return impl{}
}

type impl struct {
}

func (i impl) Foo(context.Context, *empty.Empty) (*empty.Empty, error) {
	return &empty.Empty{}, nil
}
func (i impl) Bar(context.Context, *empty.Empty) (*empty.Empty, error) {
	return &empty.Empty{}, nil
}
func (i impl) Baz(context.Context, *empty.Empty) (*empty.Empty, error) {
	return &empty.Empty{}, nil
}