RPC(remote procedure call)远程过程调用
gRPC
谷歌的rpc框架,它的idl是 Protocol Buffers
idl(interface definition language 接口描述语言)
四种服务类型
- Unary
- client-side streaming
- server-side streaming
- bidirectional-streaming
ProtoBuf
/*
描述服务
1、GetFeature:输入一个Point,返回这个点的Fearture
2、ListFearchs,(输入为一个Rectangle,输出流这个区域内所有的Fearture)
3、RecordRoute,(输入流位每个时间点的Point,返回一个RouteSammary)
4、Recommend,(输入流RecommendationRequest,输出流Fearture)
*/
syntax ="proto3";
//option go_package
package route;
message Point{
int32 latitude = 1;
int32 longitude = 2;
}
message Rectangle{
Point lo = 1;
Point hi = 2;
}
message Fearture{
string name = 1;
Point location = 2;
}
message RouteSammary{
int32 pointCount =1;
int32 distance =2;
int32 elapsedTime = 3;
}
enum RecommendationMode{
GetFarthest = 0;
GetNearest = 1;
}
message RecommendationRequest{
RecommendationMode mode =1;
Point point =2;
}
service RouteService{
//unary
rpc GetFeature(Point) returns (Fearture){}
//server side streaming
rpc ListFeature(Rectangle) returns (stream Fearture){}
//client side streaming
rpc RecordRoute(stream Point) returns (RouteSammary){}
//bidirectional streaming
rpc Recommend(stream RecommendationRequest) returns (stream Fearture){}
}
输入命令:
protoc --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative route.proto
go-out=. .代表当前文件
go-opt:记录一些我们想定义的选项
意思为:把输出文件存在相对于这个 . (route.proto)的位置,命令分为前后两部分,因为会生成两个文件。
调用
上面的proto文件运行了以后我们写一个客户端和一个服务端做测试
我把函数拆开来写,方便看一点
server.go
package main
import (
"context"
pb "github.com/HanFa/learn-go/grpc-example/route"
"google.golang.org/grpc"
"google.golang.org/protobuf/proto"
"log"
"net"
)
type routeGuidServer struct {
dbFeartures []*pb.Fearture
//之所以需要原因是protoc在解析 。proto,创建grpc.pb.go文件时,用UnimplementedXXX完成向前兼容,
pb.UnimplementedRouteServiceServer
}
func newServer() *routeGuidServer {
return &routeGuidServer{
dbFeartures: []*pb.Fearture{
{
Name: "湘潭大学",
Location: &pb.Point{
Latitude: 12331221,
Longitude: 23321233,
},
},
{
Name: "xx学院",
Location: &pb.Point{
Latitude: 12331323,
Longitude: 23323213,
},
},
},
}
}
func main() {
listen, err := net.Listen("tcp", "localhost:8080")
if err != nil {
log.Fatalf("cant create socket: %v", err)
}
grpcServer := grpc.NewServer()
pb.RegisterRouteServiceServer(grpcServer, newServer())
log.Fatalln(grpcServer.Serve(listen))
}
GetFearture()
func (r *routeGuidServer) GetFeature(ctx context.Context, point *pb.Point) (*pb.Fearture, error) {
for _, fearture := range r.dbFeartures {
if proto.Equal(fearture.Location, point) {
return fearture, nil
}
}
return nil, nil
}
ListFearture()
func (r *routeGuidServer) ListFeature(rectangle *pb.Rectangle, serverStream pb.RouteService_ListFeatureServer) error {
for _, fearture := range r.dbFeartures {
if inRange(fearture.Location, rectangle) {
if err := serverStream.Send(fearture); err != nil {
return err
}
}
}
return nil
}
RecordRoute()
func (r *routeGuidServer) RecordRoute(stream pb.RouteService_RecordRouteServer) error {
startTime := time.Now()
var pointCount, distance int32
var prePoint *pb.Point
for {
point, err := stream.Recv()
if err == io.EOF {
endTime := time.Now()
return stream.SendAndClose(&pb.RouteSammary{
Distance: distance,
PointCount: pointCount,
ElapsedTime: int32(endTime.Sub(startTime).Seconds())},
)
}
if err != nil {
return err
}
pointCount++
if prePoint != nil {
distance += 100
}
prePoint = point
}
return nil
}
Recommend()
func (r *routeGuidServer) Recommend(stream pb.RouteService_RecommendServer) error {
for {
_, err := stream.Recv()
if err == io.EOF {
return nil
}
if err != nil {
return err
}
reco := &pb.Fearture{
Name: "recommend",
Location: &pb.Point{
Latitude: int32(rand.Intn(100000)),
Longitude: int32(rand.Intn(100000)),
},
}
return stream.Send(reco)
}
return nil
}
client.go
func main() {
conn, err := grpc.Dial("localhost:8080", grpc.WithInsecure(), grpc.WithBlock())
if err != nil {
log.Fatalf("create client error: %v", err)
}
defer conn.Close()
client := pb.NewRouteServiceClient(conn)
runFirst(client) //第一个
//runSecond(client) //第二个
//runThird(client) //第三个
//runFourth(client) //第四个
}
测试运行的函数
runfirst()
func runFirst(clent pb.RouteServiceClient) {
feature, err := clent.GetFeature(context.Background(), &pb.Point{
Latitude: 12331221,
Longitude: 23321233,
})
if err != nil {
log.Fatalln(err)
}
fmt.Println(feature)
}
runSecond()
func runSecond(clent pb.RouteServiceClient) {
serverStream, err := clent.ListFeature(context.Background(), &pb.Rectangle{
Lo: &pb.Point{Latitude: 12331221, Longitude: 23321233},
Hi: &pb.Point{Latitude: 12331323, Longitude: 23323213},
})
if err != nil {
log.Fatalln(err)
}
for {
feature, err := serverStream.Recv()
if err == io.EOF {
break
}
if err != nil {
log.Fatalln(err)
}
fmt.Println(feature)
}
return
}
ruThird()
func runThird(client pb.RouteServiceClient) {
points := []*pb.Point{
{Latitude: 12331211, Longitude: 23321223},
{Latitude: 11111111, Longitude: 22222222},
{Latitude: 12321333, Longitude: 23312312},
}
clientStream, err := client.RecordRoute(context.Background())
if err != nil {
log.Fatalln(err)
}
for _, point := range points {
if err := clientStream.Send(point); err != nil {
log.Fatalln(err)
}
time.Sleep(time.Second)
}
recv, err := clientStream.CloseAndRecv()
if err != nil {
log.Fatalln(err)
}
fmt.Println(recv)
}
runFourth()
func runFourth(client pb.RouteServiceClient) {
clientStream, err := client.Recommend(context.Background())
if err != nil {
log.Fatalln(err)
}
//一直从server拉取
go func() {
feature, err := clientStream.Recv()
if err != nil {
log.Fatalln(err)
}
fmt.Println("Recommended: ", feature)
}()
reader := bufio.NewReader(os.Stdin)
for {
request := pb.RecommendationRequest{Point: &pb.Point{}}
var mode int32
fmt.Println("Enter Recommendation Mode (o for nearest,1 for farthest)")
readIntFromCommandLine(reader, &mode)
fmt.Println("Enter Latitude: ")
readIntFromCommandLine(reader, &request.Point.Latitude)
fmt.Println("Enter Longitude: : ")
readIntFromCommandLine(reader, &request.Point.Longitude)
request.Mode = pb.RecommendationMode(mode)
if err := clientStream.Send(&request); err != nil {
log.Fatalln(err)
}
//防止可能的overlap
time.Sleep(100 * time.Millisecond)
}
}