Graceful restart or stop

Do you want to graceful restart or stop your web server? There are some ways this can be done.

We can use fvbock/endless to replace the default ListenAndServe. Refer issue #296 for more details.

[...]

router := gin.Default()
router.GET("/", handler)
endless.ListenAndServe(":4242", router)

An alternative to endless:

• manners: A polite Go HTTP server that shuts down gracefully.
• graceful: Graceful is a Go package enabling graceful shutdown of an http.Handler server.
• grace: Graceful restart & zero downtime deploy for Go servers.

If you are using Go 1.8 and later, you may not need to use this library! Consider using http.Server’s built-in Shutdown() method for graceful shutdowns. See the full graceful-shutdown example with gin.

//go:build go1.8
// +build go1.8

package main

import (
  "context"
  "log"
  "net/http"
  "os"
  "os/signal"
  "syscall"
  "time"

  "github.com/gin-gonic/gin"
)

func main() {
  router := gin.Default()
  router.GET("/", func(c *gin.Context) {
    time.Sleep(5 * time.Second)
    c.String(http.StatusOK, "Welcome Gin Server")
  })

  srv := &http.Server{
    Addr:    ":8080",
    Handler: router.Handler(),
  }

  go func() {
    // service connections
    if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
      log.Fatalf("listen: %s\n", err)
    }
  }()

  // Wait for interrupt signal to gracefully shutdown the server with
  // a timeout of 5 seconds.
  quit := make(chan os.Signal, 1)
  // kill (no params) by default sends syscall.SIGTERM
  // kill -2 is syscall.SIGINT
  // kill -9 is syscall.SIGKILL but can't be caught, so don't need add it
  signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
  <-quit
  log.Println("Shutdown Server ...")

  ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
  defer cancel()
  if err := srv.Shutdown(ctx); err != nil {
    log.Println("Server Shutdown:", err)
  }
  // catching ctx.Done(). timeout of 5 seconds.
  <-ctx.Done()
  log.Println("timeout of 5 seconds.")
  log.Println("Server exiting")
}