func main() {
	// Print nirvana banner.
	fmt.Println(nirvana.Logo, nirvana.Banner)

	// Create nirvana command.
	cmd := config.NewNamedNirvanaCommand("server", config.NewDefaultOption())

	// Create plugin options.
	metricsOption := metrics.NewDefaultOption() // Metrics plugin.
	reqlogOption := reqlog.NewDefaultOption()   // Request log plugin.
	versionOption := pversion.NewOption(        // Version plugin.
		"helloworld",
		version.Version,
		version.Commit,
		version.Package,
	)

	// Enable plugins.
	cmd.EnablePlugin(metricsOption, reqlogOption, versionOption)

	// Create server config.
	serverConfig := nirvana.NewConfig()

	f, err := os.OpenFile("testlogfile", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
	if err != nil {
		fmt.Printf("Failed to open the file: %v", err)
		os.Exit(1)
	}
	defer f.Close()

	// Configure APIs. These configurations may be changed by plugins.
	serverConfig.Configure(
		nirvana.Logger(log.NewGoStandardLogger(0, f, "test", stdlog.LstdFlags)),
		nirvana.Filter(filters.Filters()...),
		nirvana.Modifier(modifiers.Modifiers()...),
		nirvana.Descriptor(apis.Descriptor()),
	)

	// Set nirvana command hooks.
	cmd.SetHook(&config.NirvanaCommandHookFunc{
		PreServeFunc: func(config *nirvana.Config, server nirvana.Server) error {
			// Output project information.
			config.Logger().Infof("Package:%s Version:%s Commit:%s", version.Package, version.Version, version.Commit)
			return nil
		},
	})

	// Start with server config.
	if err := cmd.ExecuteWithConfig(serverConfig); err != nil {
		serverConfig.Logger().Fatal(err)
	}
}