Function scheduleDelayedHydrating

packages/core/src/defer/triggering.ts:131–150

(
  scheduleFn: (callback: VoidFunction, injector: Injector) => VoidFunction,
  lView: LView,
  tNode: TNode,
)

 * Schedules hydration triggering of a defer block for `on idle` and `on timer` conditions.
 */
export function scheduleDelayedHydrating(
  scheduleFn: (callback: VoidFunction, injector: Injector) => VoidFunction,
  lView: LView,
  tNode: TNode,
) {
  if (typeof ngServerMode !== 'undefined' && ngServerMode) return;

  // Only trigger the scheduled trigger on the browser
  // since we don't want to delay the server response.
  const injector = lView[INJECTOR];
  const lDetails = getLDeferBlockDetails(lView, tNode);
  const ssrUniqueId = lDetails[SSR_UNIQUE_ID]!;
  ngDevMode && assertSsrIdDefined(ssrUniqueId);

  const cleanupFn = scheduleFn(
    () => triggerHydrationFromBlockName(injector, ssrUniqueId),
    injector,
  );
  storeTriggerCleanupFn(TriggerType.Hydrate, lDetails, cleanupFn);
}

/**
 * Trigger prefetching of dependencies for a defer block.