Give an easier and more permant solution for https://github.com/kataras/iris/pull/689

Former-commit-id: 8dc16d15f7bd14cb98b91b16d7d6b1bd756132bd

_examples/README.md

@@ -31,7 +31,8 @@ It doesn't always contain the "best ways" but it does cover each important featu
 - Graceful Shutdown
     * [using the `RegisterOnInterrupt`](http-listening/graceful-shutdown/default-notifier/main.go)
     * [using a custom notifier](http-listening/graceful-shutdown/custom-notifier/main.go)
-   
+    * [notify on shutdown](http-listening/graceful-shutdown/notify-on-shutdown/main.go)
+
 ### Configuration
 
 - [Functional](configuration/functional/main.go)

_examples/http-listening/notify-on-shutdown/main.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	stdContext "context"
+	"time"
+
+	"github.com/kataras/iris"
+	"github.com/kataras/iris/context"
+	"github.com/kataras/iris/core/host"
+)
+
+func main() {
+	app := iris.New()
+
+	app.Get("/", func(ctx context.Context) {
+		ctx.HTML("<h1>Hello, try to refresh the page after ~10 secs</h1>")
+	})
+
+	app.Logger().Info("Wait 10 seconds and check your terminal again")
+	// simulate a shutdown action here...
+	go func() {
+		<-time.After(10 * time.Second)
+		timeout := 5 * time.Second
+		ctx, cancel := stdContext.WithTimeout(stdContext.Background(), timeout)
+		defer cancel()
+		// close all hosts, this will notify the callback we had register
+		// inside the `configureHost` func.
+		app.Shutdown(ctx)
+	}()
+
+	// start the server as usual, the only difference is that
+	// we're adding a second (optional) function
+	// to configure the just-created host supervisor.
+	//
+	// http://localhost:8080
+	// wait 10 seconds and check your terminal.
+	app.Run(iris.Addr(":8080", configureHost), iris.WithoutServerError(iris.ErrServerClosed))
+
+}
+
+func configureHost(su *host.Supervisor) {
+	// here we have full access to the host that will be created
+	// inside the `Run` function.
+	//
+	// we register a shutdown "event" callback
+	su.RegisterOnShutdown(func() {
+		println("server is closed")
+	})
+	// su.RegisterOnError
+	// su.RegisterOnServe
+}