Function renderInternal

packages/platform-server/src/utils.ts:197–234

(
  platformRef: PlatformRef,
  applicationRef: ApplicationRef,
)

 * @returns A promise that resolves to the rendered string.
 */
export async function renderInternal(
  platformRef: PlatformRef,
  applicationRef: ApplicationRef,
): Promise<string> {
  const platformState = platformRef.injector.get(PlatformState);
  prepareForHydration(platformState, applicationRef);
  appendServerContextInfo(applicationRef);

  // Run any BEFORE_APP_SERIALIZED callbacks just before rendering to string.
  const environmentInjector = applicationRef.injector;
  const errorHandler = environmentInjector.get(INTERNAL_APPLICATION_ERROR_HANDLER);
  const callbacks = environmentInjector.get(BEFORE_APP_SERIALIZED, null);
  if (callbacks) {
    const asyncCallbacks: Promise<void>[] = [];
    for (const callback of callbacks) {
      try {
        const callbackResult = callback();
        if (callbackResult) {
          asyncCallbacks.push(callbackResult);
        }
      } catch (e) {
        // Delegate to the application's ErrorHandler so custom handlers
        // (e.g. Sentry) are notified, rather than writing directly to console.
        errorHandler(e);
      }
    }

    if (asyncCallbacks.length) {
      for (const result of await Promise.allSettled(asyncCallbacks)) {
        if (result.status === 'rejected') {
          errorHandler(result.reason);
        }
      }
    }
  }

  return platformState.renderToString();
}

/**
 * Destroy the application in a macrotask, this allows pending promises to be settled and errors