```Dockerfile
# ⛔️ Não faça assim
CMD fastapi run app/main.py --port 80
```

Garanta que você sempre use a forma **exec** para assegurar que o FastAPI consiga encerrar graciosamente e que os [eventos de lifespan](../advanced/events.md) sejam disparados.

Você pode ler mais na [documentação do Docker sobre as formas shell e exec](https://docs.docker.com/reference/dockerfile/#shell-and-exec-form).

 *
 * <p>To post an event, simply provide the event object to the {@link #post(Object)} method. The
 * EventBus instance will determine the type of event and route it to all registered listeners.
 *
 * <p>Events are routed based on their type &mdash; an event will be delivered to any subscriber for
 * any type to which the event is assignable. This includes implemented interfaces, all

{* ../../docs_src/events/tutorial001_py310.py hl[8] *}

Bu durumda `startup` event handler fonksiyonu, "database" öğesini (sadece bir `dict`) bazı değerlerle başlatır.

Birden fazla event handler fonksiyonu ekleyebilirsiniz.

Ve tüm `startup` event handler’ları tamamlanmadan uygulamanız request almaya başlamaz.

### `shutdown` eventi { #shutdown-event }

In this case, the `startup` event handler function will initialize the items "database" (just a `dict`) with some values.

You can add more than one event handler function.

And your application won't start receiving requests until all the `startup` event handlers have completed.

### `shutdown` event { #shutdown-event }

To add a function that should be run when the application is shutting down, declare it with the event `"shutdown"`:

# Server-Sent Events (SSE) { #server-sent-events-sse }

Puedes enviar datos en streaming al cliente usando **Server-Sent Events** (SSE).

Esto es similar a [Stream JSON Lines](stream-json-lines.md), pero usa el formato `text/event-stream`, que los navegadores soportan de forma nativa con la [`EventSource` API](https://developer.mozilla.org/en-US/docs/Web/API/EventSource).

/// info | Información

Añadido en FastAPI 0.135.0.

///

        // Create different implementations
        SearchLogEvent event1 = new TestSearchLogEvent("id1", 1L, "type1");
        SearchLogEvent event2 = new NullSearchLogEvent();
        SearchLogEvent event3 = new EmptySearchLogEvent();

        // Test polymorphic behavior
        SearchLogEvent[] events = { event1, event2, event3 };

        for (SearchLogEvent event : events) {
            // All methods should be callable without exceptions

{* ../../docs_src/events/tutorial003_py310.py hl[22] *}

## Événements alternatifs (déprécié) { #alternative-events-deprecated }

/// warning | Alertes

事件函数既可以声明为异步函数（`async def`），也可以声明为普通函数（`def`）。

### `startup` 事件 { #startup-event }

使用事件 `"startup"` 声明一个在应用启动前运行的函数：

{* ../../docs_src/events/tutorial001_py310.py hl[8] *}

本例中，`startup` 事件处理器函数为项目“数据库”（只是一个 `dict`）提供了一些初始值。

**FastAPI** 支持多个事件处理器函数。

只有所有 `startup` 事件处理器运行完毕，**FastAPI** 应用才开始接收请求。

### `shutdown` 事件 { #shutdown-event }

使用事件 `"shutdown"` 声明一个在应用关闭时运行的函数：

Параметр `lifespan` приложения `FastAPI` принимает асинхронный менеджер контекста, поэтому мы можем передать ему наш новый асинхронный менеджер контекста `lifespan`.

{* ../../docs_src/events/tutorial003_py310.py hl[22] *}

## Альтернативные события (устаревшие) { #alternative-events-deprecated }

/// warning | Предупреждение

Diese Funktionen können mit `async def` oder normalem `def` deklariert werden.

### `startup`-Event { #startup-event }

Um eine Funktion hinzuzufügen, die vor dem Start der Anwendung ausgeführt werden soll, deklarieren Sie diese mit dem Event `startup`:

{* ../../docs_src/events/tutorial001_py310.py hl[8] *}