Function callAppShutdownHook

packages/core/hooks/on-app-shutdown.hook.ts:45–74

(
  module: Module,
  signal?: string,
)

 * @param signal
 */
export async function callAppShutdownHook(
  module: Module,
  signal?: string,
): Promise<any> {
  const providers = module.getNonAliasProviders();
  // Module (class) instance is the first element of the providers array
  // Lifecycle hook has to be called once all classes are properly initialized
  const [_, moduleClassHost] = providers.shift()!;
  const instances = [
    ...module.controllers,
    ...providers,
    ...module.injectables,
    ...module.middlewares,
  ];

  const nonTransientInstances = getNonTransientInstances(instances);
  await Promise.all(callOperator(nonTransientInstances, signal));
  const transientInstances = getTransientInstances(instances);
  await Promise.all(callOperator(transientInstances, signal));

  // Call the instance itself
  const moduleClassInstance = moduleClassHost.instance;
  if (
    moduleClassInstance &&
    hasOnAppShutdownHook(moduleClassInstance) &&
    moduleClassHost.isDependencyTreeStatic()
  ) {
    await moduleClassInstance.onApplicationShutdown(signal);
  }
}