timeout.md

超时

超时是防止服务端被大量请求压垮的一种机制。

• gRPC 天然支持超时
• HTTP Leo提供了和gRPC用法一样的超时机制。

示例

Http 客户端

package main

import (
	"context"
	"github.com/go-leo/leo/v3/example/api/helloworld/v1"
	"log"
	"time"
)

func main() {
	client := helloworld.NewGreeterHttpClient("localhost:60051")
	// 设置超时时间为1秒
	ctx, cancelFunc := context.WithTimeout(context.Background(), 1*time.Second)
	defer cancelFunc()
	r, err := client.SayHello(ctx, &helloworld.HelloRequest{})
	if err != nil {
		log.Fatalf("could not greet: %v", err)
	}
	log.Printf("Greeting: %s", r.GetMessage())
}

服务端

package main

import (
	"context"
	"github.com/go-leo/leo/v3"
	"github.com/go-leo/leo/v3/example/api/helloworld/v1"
	"github.com/go-leo/leo/v3/serverx/grpcserverx"
	"github.com/go-leo/leo/v3/serverx/httpserverx"
	"github.com/go-leo/leo/v3/transportx/grpctransportx"
	"github.com/gorilla/mux"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
	"log"
	"time"
)

func main() {
	client := helloworld.NewGreeterGrpcClient("localhost:50051", grpctransportx.WithDialOptions(grpc.WithTransportCredentials(insecure.NewCredentials())))
	router := helloworld.AppendGreeterHttpServerRoutes(mux.NewRouter(), client)
	httpSrv := httpserverx.NewServer(router, httpserverx.Port(60051))

	grpcSrv := grpcserverx.NewServer(grpcserverx.Port(50051))
	helloworld.RegisterGreeterServer(grpcSrv, helloworld.NewGreeterGrpcServer(&server{}))

	if err := leo.NewApp(leo.Runner(httpSrv, grpcSrv)).Run(context.Background()); err != nil {
		log.Fatalf("failed to serve: %v", err)
	}
}

type server struct{}

func (s *server) SayHello(ctx context.Context, in *helloworld.HelloRequest) (*helloworld.HelloReply, error) {
	// 获取超时时间
	deadline, ok := ctx.Deadline()
	log.Printf("timeout: %v, %v", deadline, ok)
	// 模拟超时
	time.Sleep(10 * time.Second)
	log.Printf("after timeout")
	return &helloworld.HelloReply{Message: "Hello " + in.GetName()}, nil
}

代码timeout