本示例演示如何在 Dubbo-go 客户端发起调用时设置请求超时时间。可在此查看 完整示例源码地址
在创建客户端时,可以使用 client.WithRequestTimeout() 方法设置全局超时时间(所有使用改 client 的服务代理共享)。
    cli, err := client.NewClient(
        client.WithClientURL("tri://127.0.0.1:20000"),
        client.WithClientRequestTimeout(3 * time.Second),
    )
可以使用 client.WithRequestTimeout() 创建服务粒度的超时时间(以下服务代理 svc 发起的方法调用都使用这个时间)。
   svc, err := greet.NewGreetService(cli, client.WithRequestTimeout(5 * time.Second))
也可以在调用发起时,使用 client.WithCallRequestTimeout() 指定一个超时时间
resp, err := svc.GreetTimeout(context.Background(), &greet.GreetRequest{Name: "hello world"}, client.WithCallRequestTimeout(10 * time.Second))
从上往下,以上三种方式的优先级逐步提高,client.WithCallRequestTimeout() 指定的超时时间优先级最高。
源文件路径:dubbo-go-sample/timeout/proto/greet.proto
syntax = "proto3";
package greet;
option go_package = "github.com/apache/dubbo-go-samples/timeout/proto;greet";
message GreetRequest {
  string name = 1;
}
message GreetResponse {
  string greeting = 1;
}
service GreetService {
  rpc Greet(GreetRequest) returns (GreetResponse) {}
  rpc GreetTimeout(GreetRequest) returns (GreetResponse) {}
}
Greet方法直接响应,GreetTimeout方法等待五秒后响应(模拟超时)。
源文件路径:dubbo-go-sample/timeout/go-server/handler.go
package main
import (
   "context"
   "time"
   greet "github.com/apache/dubbo-go-samples/timeout/proto"
)
type GreetTripleServer struct {
}
func (srv *GreetTripleServer) Greet(ctx context.Context, req *greet.GreetRequest) (*greet.GreetResponse, error) {
   resp := &greet.GreetResponse{Greeting: req.Name}
   return resp, nil
}
func (srv *GreetTripleServer) GreetTimeout(ctx context.Context, req *greet.GreetRequest) (*greet.GreetResponse, error) {
   time.Sleep(5 * time.Second)
   resp := &greet.GreetResponse{Greeting: req.Name}
   return resp, nil
}
客户端client文件,创建客户端,设置超时时间为3s,分别请求Greet和GreetTimeout,输出响应结果。
源文件路径:dubbo-go-sample/timeout/go-client/client.go
package main
import (
	"context"
	"time"
	"dubbo.apache.org/dubbo-go/v3/client"
	_ "dubbo.apache.org/dubbo-go/v3/imports"
	greet "github.com/apache/dubbo-go-samples/timeout/proto"
	"github.com/dubbogo/gost/log/logger"
)
func main() {
	cli, err := client.NewClient(
		client.WithClientURL("tri://127.0.0.1:20000"),
		client.WithClientRequestTimeout(3*time.Second),
	)
	if err != nil {
		panic(err)
	}
	svc, err := greet.NewGreetService(cli)
	if err != nil {
		panic(err)
	}
	// test timeout
	resp, err := svc.GreetTimeout(context.Background(), &greet.GreetRequest{Name: "hello world"})
	if err != nil {
		logger.Error("call [greet.GreetService.GreetTimeout] service timeout")
		logger.Error(err)
	} else {
		logger.Infof("Greet response: %s", resp.Greeting)
	}
	// test normal
	resp, err = svc.Greet(context.Background(), &greet.GreetRequest{Name: "hello world"})
	if err != nil {
		logger.Error(err)
	}
	logger.Infof("Greet response: %s", resp.Greeting)
}
先启动服务端,再启动客户端,可以观察到GreetTimeout请求响应超时,Greet请求响应正常
[call [greet.GreetService.GreetTimeout] service timeout]
Greet response: [hello world]