added fasthttp example

examples/fasthttp/main.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"github.com/valyala/fasthttp"
+	"golang.ngrok.com/ngrok"
+	"golang.ngrok.com/ngrok/config"
+)
+
+func main() {
+	if err := run(context.Background()); err != nil {
+		log.Fatalf("main: %v", err)
+	}
+}
+
+func run(ctx context.Context) error {
+	tun, err := ngrok.Listen(ctx,
+		config.HTTPEndpoint(),
+		ngrok.WithAuthtokenFromEnv(),
+	)
+	if err != nil {
+		return err
+	}
+	log.Println("tunnel created:", tun.URL())
+
+	var serv fasthttp.Server
+
+	serv.Handler = func(ctx *fasthttp.RequestCtx) {
+		fmt.Fprintf(ctx, "Hello! You're requesting %q", ctx.RequestURI())
+	}
+
+	serv.Serve(tun)
+
+	return nil
+}