grpc在golang_cpp_python下的实践

1. 下载protocbuf 生成器

https://github.com/protocolbuffers/protobuf/releases

cd protoc-3.9.0-osx-x86_64 
cp -r include/ /usr/local/include/ 
cp -r bin/ /usr/local/bin/
protoc --version

2. golang版本

1 2	go get -u google.golang.org/grpc go get -u github.com/golang/protobuf/protoc-gen-go

我们去 $GOPATH/src/google.golang.org/grpc/examples 看helloworld例子

1	cd $GOPATH/src/google.golang.org/grpc/examples/helloworld

helloworld.proto

syntax = "proto3";

option java_multiple_files = true;
option java_package = "io.grpc.examples.helloworld";
option java_outer_classname = "HelloWorldProto";

package helloworld;

// The greeting service definition.
service Greeter {
  // Sends a greeting
  rpc SayHello (HelloRequest) returns (HelloReply) {}
}

// The request message containing the user's name.
message HelloRequest {
  string name = 1;
}

// The response message containing the greetings
message HelloReply {
  string message = 1;
}

我们通过.proto文件生成golang文件, 生成后的文件不要编辑.

protoc -I helloworld/ helloworld/helloworld.proto --go_out=plugins=grpc:helloworld

# 获取进入到helloworld目录里
protoc helloworld.proto --go_out=plugins=grpc:.

helloworld.pb.go

// Code generated by protoc-gen-go. DO NOT EDIT.
// source: helloworld.proto

package helloworld

import (
	context "context"
	fmt "fmt"
	proto "github.com/golang/protobuf/proto"
	grpc "google.golang.org/grpc"
	codes "google.golang.org/grpc/codes"
	status "google.golang.org/grpc/status"
	math "math"
)

// Reference imports to suppress errors if they are not otherwise used.
var _ = proto.Marshal
var _ = fmt.Errorf
var _ = math.Inf

// This is a compile-time assertion to ensure that this generated file
// is compatible with the proto package it is being compiled against.
// A compilation error at this line likely means your copy of the
// proto package needs to be updated.
const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package

// The request message containing the user's name.
type HelloRequest struct {
	Name                 string   `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`
	XXX_NoUnkeyedLiteral struct{} `json:"-"`
	XXX_unrecognized     []byte   `json:"-"`
	XXX_sizecache        int32    `json:"-"`
}

func (m *HelloRequest) Reset()         { *m = HelloRequest{} }
func (m *HelloRequest) String() string { return proto.CompactTextString(m) }
func (*HelloRequest) ProtoMessage()    {}
func (*HelloRequest) Descriptor() ([]byte, []int) {
	return fileDescriptor_17b8c58d586b62f2, []int{0}
}

func (m *HelloRequest) XXX_Unmarshal(b []byte) error {
	return xxx_messageInfo_HelloRequest.Unmarshal(m, b)
}
func (m *HelloRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
	return xxx_messageInfo_HelloRequest.Marshal(b, m, deterministic)
}
func (m *HelloRequest) XXX_Merge(src proto.Message) {
	xxx_messageInfo_HelloRequest.Merge(m, src)
}
func (m *HelloRequest) XXX_Size() int {
	return xxx_messageInfo_HelloRequest.Size(m)
}
func (m *HelloRequest) XXX_DiscardUnknown() {
	xxx_messageInfo_HelloRequest.DiscardUnknown(m)
}

var xxx_messageInfo_HelloRequest proto.InternalMessageInfo

func (m *HelloRequest) GetName() string {
	if m != nil {
		return m.Name
	}
	return ""
}

// The response message containing the greetings
type HelloReply struct {
	Message              string   `protobuf:"bytes,1,opt,name=message,proto3" json:"message,omitempty"`
	XXX_NoUnkeyedLiteral struct{} `json:"-"`
	XXX_unrecognized     []byte   `json:"-"`
	XXX_sizecache        int32    `json:"-"`
}

func (m *HelloReply) Reset()         { *m = HelloReply{} }
func (m *HelloReply) String() string { return proto.CompactTextString(m) }
func (*HelloReply) ProtoMessage()    {}
func (*HelloReply) Descriptor() ([]byte, []int) {
	return fileDescriptor_17b8c58d586b62f2, []int{1}
}

func (m *HelloReply) XXX_Unmarshal(b []byte) error {
	return xxx_messageInfo_HelloReply.Unmarshal(m, b)
}
func (m *HelloReply) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
	return xxx_messageInfo_HelloReply.Marshal(b, m, deterministic)
}
func (m *HelloReply) XXX_Merge(src proto.Message) {
	xxx_messageInfo_HelloReply.Merge(m, src)
}
func (m *HelloReply) XXX_Size() int {
	return xxx_messageInfo_HelloReply.Size(m)
}
func (m *HelloReply) XXX_DiscardUnknown() {
	xxx_messageInfo_HelloReply.DiscardUnknown(m)
}

var xxx_messageInfo_HelloReply proto.InternalMessageInfo

func (m *HelloReply) GetMessage() string {
	if m != nil {
		return m.Message
	}
	return ""
}

func init() {
	proto.RegisterType((*HelloRequest)(nil), "helloworld.HelloRequest")
	proto.RegisterType((*HelloReply)(nil), "helloworld.HelloReply")
}

func init() { proto.RegisterFile("helloworld.proto", fileDescriptor_17b8c58d586b62f2) }

var fileDescriptor_17b8c58d586b62f2 = []byte{
	// 175 bytes of a gzipped FileDescriptorProto
	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x12, 0xc8, 0x48, 0xcd, 0xc9,
	0xc9, 0x2f, 0xcf, 0x2f, 0xca, 0x49, 0xd1, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0xe2, 0x42, 0x88,
	0x28, 0x29, 0x71, 0xf1, 0x78, 0x80, 0x78, 0x41, 0xa9, 0x85, 0xa5, 0xa9, 0xc5, 0x25, 0x42, 0x42,
	0x5c, 0x2c, 0x79, 0x89, 0xb9, 0xa9, 0x12, 0x8c, 0x0a, 0x8c, 0x1a, 0x9c, 0x41, 0x60, 0xb6, 0x92,
	0x1a, 0x17, 0x17, 0x54, 0x4d, 0x41, 0x4e, 0xa5, 0x90, 0x04, 0x17, 0x7b, 0x6e, 0x6a, 0x71, 0x71,
	0x62, 0x3a, 0x4c, 0x11, 0x8c, 0x6b, 0xe4, 0xc9, 0xc5, 0xee, 0x5e, 0x94, 0x9a, 0x5a, 0x92, 0x5a,
	0x24, 0x64, 0xc7, 0xc5, 0x11, 0x9c, 0x58, 0x09, 0xd6, 0x25, 0x24, 0xa1, 0x87, 0xe4, 0x02, 0x64,
	0xcb, 0xa4, 0xc4, 0xb0, 0xc8, 0x14, 0xe4, 0x54, 0x2a, 0x31, 0x38, 0x19, 0x70, 0x49, 0x67, 0xe6,
	0xeb, 0xa5, 0x17, 0x15, 0x24, 0xeb, 0xa5, 0x56, 0x24, 0xe6, 0x16, 0xe4, 0xa4, 0x16, 0x23, 0xa9,
	0x75, 0xe2, 0x07, 0x2b, 0x0e, 0x07, 0xb1, 0x03, 0x40, 0x5e, 0x0a, 0x60, 0x4c, 0x62, 0x03, 0xfb,
	0xcd, 0x18, 0x10, 0x00, 0x00, 0xff, 0xff, 0x0f, 0xb7, 0xcd, 0xf2, 0xef, 0x00, 0x00, 0x00,
}

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

// 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.SupportPackageIsVersion4

// GreeterClient is the client API for Greeter service.
//
// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
type GreeterClient interface {
	// Sends a greeting
	SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloReply, error)
}

type greeterClient struct {
	cc *grpc.ClientConn
}

func NewGreeterClient(cc *grpc.ClientConn) GreeterClient {
	return &greeterClient{cc}
}

func (c *greeterClient) SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloReply, error) {
	out := new(HelloReply)
	err := c.cc.Invoke(ctx, "/helloworld.Greeter/SayHello", in, out, opts...)
	if err != nil {
		return nil, err
	}
	return out, nil
}

// GreeterServer is the server API for Greeter service.
type GreeterServer interface {
	// Sends a greeting
	SayHello(context.Context, *HelloRequest) (*HelloReply, error)
}

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

func (*UnimplementedGreeterServer) SayHello(ctx context.Context, req *HelloRequest) (*HelloReply, error) {
	return nil, status.Errorf(codes.Unimplemented, "method SayHello not implemented")
}

func RegisterGreeterServer(s *grpc.Server, srv GreeterServer) {
	s.RegisterService(&_Greeter_serviceDesc, srv)
}

func _Greeter_SayHello_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
	in := new(HelloRequest)
	if err := dec(in); err != nil {
		return nil, err
	}
	if interceptor == nil {
		return srv.(GreeterServer).SayHello(ctx, in)
	}
	info := &grpc.UnaryServerInfo{
		Server:     srv,
		FullMethod: "/helloworld.Greeter/SayHello",
	}
	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
		return srv.(GreeterServer).SayHello(ctx, req.(*HelloRequest))
	}
	return interceptor(ctx, in, info, handler)
}

var _Greeter_serviceDesc = grpc.ServiceDesc{
	ServiceName: "helloworld.Greeter",
	HandlerType: (*GreeterServer)(nil),
	Methods: []grpc.MethodDesc{
		{
			MethodName: "SayHello",
			Handler:    _Greeter_SayHello_Handler,
		},
	},
	Streams:  []grpc.StreamDesc{},
	Metadata: "helloworld.proto",
}

我们看下greeter_server 的代码并且启动: go run greeter_server/main.go

package main

import (
	"context"
	"log"
	"net"

	"google.golang.org/grpc"
	pb "google.golang.org/grpc/examples/helloworld/helloworld"
)

const (
	port = ":50051"
)

// server is used to implement helloworld.GreeterServer.
type server struct{}

// SayHello implements helloworld.GreeterServer
func (s *server) SayHello(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
	log.Printf("Received: %v", in.Name)
	return &pb.HelloReply{Message: "Hello " + in.Name}, nil
}

func main() {
	lis, err := net.Listen("tcp", port)
	if err != nil {
		log.Fatalf("failed to listen: %v", err)
	}
	s := grpc.NewServer()
	pb.RegisterGreeterServer(s, &server{})
	if err := s.Serve(lis); err != nil {
		log.Fatalf("failed to serve: %v", err)
	}
}

我们看下greeter_client的代码并且启动:go run greeter_client/main.go

package main

import (
	"context"
	"log"
	"os"
	"time"

	"google.golang.org/grpc"
	pb "google.golang.org/grpc/examples/helloworld/helloworld"
)

const (
	address     = "localhost:50051"
	defaultName = "world"
)

func main() {
	// Set up a connection to the server.
	conn, err := grpc.Dial(address, grpc.WithInsecure())
	if err != nil {
		log.Fatalf("did not connect: %v", err)
	}
	defer conn.Close()
	c := pb.NewGreeterClient(conn)

	// Contact the server and print out its response.
	name := defaultName
	if len(os.Args) > 1 {
		name = os.Args[1]
	}
	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
	defer cancel()
	r, err := c.SayHello(ctx, &pb.HelloRequest{Name: name})
	if err != nil {
		log.Fatalf("could not greet: %v", err)
	}
	log.Printf("Greeting: %s", r.Message)
}

If things go smoothly, you will see the Greeting: Hello world in the client side output.

Congratulations! You’ve just run a client-server application with gRPC.

2.1 修改proto步骤总结

在proto文件里增加 rpc SayHelloAgain (HelloRequest) returns (HelloReply) {}的定义
通过protoc重新生成golang文件, 里面增加了SayHelloAgain相关方法

修改server文件增加方法来实现接口

1
2
3

func (s *server) SayHelloAgain(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
        return &pb.HelloReply{Message: "Hello again " + in.Name}, nil
}

修改client方法增加调用

r, err = c.SayHelloAgain(ctx, &pb.HelloRequest{Name: name})
if err != nil {
        log.Fatalf("could not greet: %v", err)
}
log.Printf("Greeting: %s", r.Message)

总结
- client调用的的SayHelloAgain是helloworld.pb.go里生成的方法
- server增加的方法是为了实现了helloworld.pb.go 生成的server新接口, 来实现callback

3. TODO: cpp 版本

参考: https://github.com/grpc/grpc/blob/master/BUILDING.md

# 安装xcode command line tools
sudo xcode-select --install
# 先安装必备的软件
brew install autoconf automake libtool shtool gflags

# 下载官方代码并更新依赖
git clone https://github.com/grpc/grpc
git submodule update --init

# 编译并且安装
LIBTOOL=glibtool LIBTOOLIZE=glibtoolize make
sudo make install

我们先进入hellworld例子

cd examples/cpp/hellworld/
make

# make过程中可以看到会先生成helloworld.pb.cc
protoc -I ../../protos --cpp_out=. ../../protos/helloworld.proto

还可以这样生成:

1 2	protoc --cpp_out=. helloworld.proto protoc --grpc_out=. --plugin=protoc-gen-grpc=`which grpc_cpp_plugin` helloworld.proto

4. TODO: python版本

1
2
3

sudo python3 -m pip install grpcio
sudo python3 -m pip install grpcio-tools
python3 -m grpc_tools.protoc -I. --python_out=. --grpc_python_out=. helloworld.proto

5. 参考资料:

https://grpc.io/docs/quickstart/