tmpl: add shutdown callbacks in generated config

templates/server/configureapi.gotmpl

@@ -22,9 +22,12 @@
   {{ imports .Imports }}
 )
 
+// Callback is a simple function
+type Callback func()
+
 // Config holds the things required to configure the API
 type Config struct {
 	Log zerolog.Logger
 	DB *sqlx.DB
 
 	BaseURL string
@@ -25,9 +28,10 @@
 // Config holds the things required to configure the API
 type Config struct {
 	Log zerolog.Logger
 	DB *sqlx.DB
 
 	BaseURL string
+	Shutdown []Callback
 	// Here you can add anything the ConfigureAPI function will need to setup
 	// the API
 }
@@ -56,6 +60,8 @@
 type ConfiguredAPI struct {
 	api *{{.Package}}.{{ pascalize .Name }}API
 	handler http.Handler
+
+	config Config
 }
 
 func (capi *ConfiguredAPI) Name() string {
@@ -70,6 +76,10 @@
 }
 
 func (capi *ConfiguredAPI) ServerShutdown() {
+	lsize := len(capi.config.Shutdown)
+	for i := range capi.config.Shutdown {
+		capi.config.Shutdown[lsize-i-1]()
+	}
 }
 
 func ConfigureAPI(api *{{.Package}}.{{ pascalize .Name }}API, server *orusapi.Server, config Config) (*ConfiguredAPI, error) {
@@ -168,6 +178,7 @@
 	return &ConfiguredAPI{
 		api: api,
 		handler: setupGlobalMiddleware(api.Serve(setupMiddlewares)),
+		config:  config,
 	}, nil
 }