}
  }

  @VisibleForTesting
  Set<Subscriber> getSubscribersForTesting(Class<?> eventType) {
    return MoreObjects.firstNonNull(subscribers.get(eventType), ImmutableSet.<Subscriber>of());
  }

  /**
   * Gets an iterator representing an immutable snapshot of all subscribers to the given event at
   * the time this method is called.
   */
  Iterator<Subscriber> getSubscribers(Object event) {

    assertEquals("Event should be available.", EVENT, handler.context.getEvent());
    assertEquals("Subscriber should be available.", subscriber, handler.context.getSubscriber());
    assertEquals(
        "Method should be available.",
        subscriber.getClass().getMethod("throwExceptionOn", String.class),
        handler.context.getSubscriberMethod());
  }

Or would you like to get help with **FastAPI**?

There are very simple ways to help (several involve just one or two clicks).

And there are several ways to get help too.

## Subscribe to the newsletter

You can subscribe to the (infrequent) [**FastAPI and friends** newsletter](newsletter.md){.internal-link target=_blank} to stay updated about:

* News about FastAPI and friends 🚀
* Guides 📝
* Features ✨

///

* Check if there's a <a href="https://github.com/fastapi/fastapi/discussions/categories/translations" class="external-link" target="_blank">GitHub Discussion</a> to coordinate translations for your language. You can subscribe to it, and when there's a new pull request to review, an automatic comment will be added to the discussion.

At a high level, each client job will find the correct generator for the request, generate the required configuration, and send it.

#### Optimizations

A naive implementation would simply regenerate all resources, of all subscribed types, for each client, on any configuration change. However, this scales poorly. As a result, we have many levels of optimizations to avoid doing this work.