Question

我正在使用https://github.com/gorilla/mux中的gorilla多样化库来构建服务器。问题是，当我使用Ctrl + C或者有特定的API调用时，我希望它能够正常关闭，例如“/ shutdown”。

我已经知道在Go 1.8中，已经实现了正常关闭。但是如何将它与大猩猩多路复用器结合起来呢？另外，如何将它与SIGINT信号结合起来？

任何人都可以告诉我该怎么做吗？

Answer 1

通道可用于通过API调用（/shutdown）或中断信号（Ctrl+C）捕获关闭请求。

将http.Server嵌入到自定义结构中，以便稍后调用http Server.Shutdown
添加频道字段（shutdownReq），以便从API调用/shutdown
在/shutdown的路由器中注册包含gorilla/mux的http处理程序，然后将路由器分配到http.Server.Handler
注册os.Interrupt/syscall.SIGINT, syscall.SIGTERM处理程序
使用select通过API调用或interrupt信号
通过调用Server.Shutdown

以下是示例代码：

package main

import (
    "context"
    "log"
    "net/http"
    "sync/atomic"
    "syscall"
    "time"

    "os"
    "os/signal"

    "github.com/gorilla/mux"
)

type myServer struct {
    http.Server
    shutdownReq chan bool
    reqCount    uint32
}

func NewServer() *myServer {
    //create server
    s := &myServer{
        Server: http.Server{
            Addr:         ":8080",
            ReadTimeout:  10 * time.Second,
            WriteTimeout: 10 * time.Second,
        },
        shutdownReq: make(chan bool),
    }

    router := mux.NewRouter()

    //register handlers
    router.HandleFunc("/", s.RootHandler)
    router.HandleFunc("/shutdown", s.ShutdownHandler)

    //set http server handler
    s.Handler = router

    return s
}

func (s *myServer) WaitShutdown() {
    irqSig := make(chan os.Signal, 1)
    signal.Notify(irqSig, syscall.SIGINT, syscall.SIGTERM)

    //Wait interrupt or shutdown request through /shutdown
    select {
    case sig := <-irqSig:
        log.Printf("Shutdown request (signal: %v)", sig)
    case sig := <-s.shutdownReq:
        log.Printf("Shutdown request (/shutdown %v)", sig)
    }

    log.Printf("Stoping http server ...")

    //Create shutdown context with 10 second timeout
    ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
    defer cancel()

    //shutdown the server
    err := s.Shutdown(ctx)
    if err != nil {
        log.Printf("Shutdown request error: %v", err)
    }
}

func (s *myServer) RootHandler(w http.ResponseWriter, r *http.Request) {
    w.Write([]byte("Hello Gorilla MUX!\n"))
}

func (s *myServer) ShutdownHandler(w http.ResponseWriter, r *http.Request) {
    w.Write([]byte("Shutdown server"))

    //Do nothing if shutdown request already issued
    //if s.reqCount == 0 then set to 1, return true otherwise false
    if !atomic.CompareAndSwapUint32(&s.reqCount, 0, 1) {
        log.Printf("Shutdown through API call in progress...")
        return
    }

    go func() {
        s.shutdownReq <- true
    }()
}

func main() {
    //Start the server
    server := NewServer()

    done := make(chan bool)
    go func() {
        err := server.ListenAndServe()
        if err != nil {
            log.Printf("Listen and serve: %v", err)
        }
        done <- true
    }()

    //wait shutdown
    server.WaitShutdown()

    <-done
    log.Printf("DONE!")
}

注意：请注意与gracefull关闭相关的this issue。

优雅地关闭大猩猩服务器

1 个答案: