How to await echo.Server shutdown completed?

[tisonkun]

Previously I wrote:

	var err error
	if s.internalServer != nil {
		s.internalServer.Start()
		err = errors.Join(err, s.internalServer.Shutdown(ctx))
	}
	if s.publicServer != nil {
		err = errors.Join(err, s.publicServer.Shutdown(ctx))
	}
	if s.store != nil {
		s.store.Close()
	}
	return err

I need to wait for the publicServer and internalServer echo servers shutdown to close the backend store. Now echo.Server has no Shutdown method, how can I easily await for its shutting down complete?

[aldas]

you could rely on context cancellation to trigger server shutdown and combine it with waitgroup

package main

import (
	"context"
	"os"
	"os/signal"
	"sync"
	"syscall"

	"github.com/labstack/echo/v5"
)

func main() {
	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer cancel()

	wg := sync.WaitGroup{}

	wg.Add(1)
	go func() {
		defer wg.Done()

		e := echo.New()
		//...
		internal := echo.StartConfig{Address: ":8080"}
		if err := internal.Start(ctx, e); err != nil {
			e.Logger.Error("failed to start internal server: ", "error", err.Error())
			cancel()
		}
		e.Logger.Info("internal server goroutine is finished")
	}()

	wg.Add(1)
	go func() {
		defer wg.Done()

		e := echo.New()
		//...
		public := echo.StartConfig{Address: ":8080"} // same port will trigger early shutdown and demonstrate coordinated shutdown
		if err := public.Start(ctx, e); err != nil {
			e.Logger.Error("failed to start public server: ", "error", err.Error())
			cancel()
		}
		e.Logger.Info("public server goroutine is finished")
	}()

	wg.Wait()
}