gRPC: 如何优雅关闭进程（graceful shutdown）？

go get github.com/rookie-ninja/rk-boot
go get github.com/rookie-ninja/rk-grpc

---
grpc:
  - name: greeter                   # Name of grpc entry
    port: 8080                      # Port of grpc entry
    enabled: true                   # Enable grpc entry

package main

import (
	"context"
	"github.com/rookie-ninja/rk-boot"
	_ "github.com/rookie-ninja/rk-grpc/boot"
)

// Application entrance.
func main() {
	// Create a new boot instance.
	boot := rkboot.NewBoot()
    
	// Add shutdown hook function
	boot.AddShutdownHookFunc("shutdown-hook", func() {
		fmt.Println("shutting down")
	})

	// Bootstrap
	boot.Bootstrap(context.Background())

	// Wait for shutdown sig
	boot.WaitForShutdownSig(context.Background())
}

$ go run main.go

shutting down