return levent.Event{
					GetObjectContext: &levent.GetObjectContext{
						OutputRoute: functionID,
						OutputToken: functionToken,
						InputS3URL:  "http://localhost/dummy",
					},
					UserRequest: levent.UserRequest{
						Headers: map[string][]string{},
					},
					UserIdentity: levent.Identity{
						PrincipalID: "test-user",
					},

	if err != nil {
		return levent.Event{}, err
	}

	ckSum := sha256.Sum256([]byte(cred.AccessKey + u.RawQuery))

	eventData := levent.Event{
		GetObjectContext: &levent.GetObjectContext{
			InputS3URL:  u.String(),
			OutputRoute: shortuuid.New(),
			OutputToken: hex.EncodeToString(ckSum[:]),
		},
		UserRequest: levent.UserRequest{
			URL:     r.URL.String(),
			Headers: r.Header.Clone(),

	"github.com/minio/minio/internal/config/subnet"
	xhttp "github.com/minio/minio/internal/http"
	etcd "go.etcd.io/etcd/client/v3"

	levent "github.com/minio/minio/internal/config/lambda/event"
	"github.com/minio/minio/internal/event"
	"github.com/minio/minio/internal/pubsub"
	"github.com/minio/pkg/v3/certs"
	"github.com/minio/pkg/v3/env"
	xnet "github.com/minio/pkg/v3/net"
)

		apiErr = ErrAdminBucketQuotaExceeded
	case *event.ErrInvalidEventName:
		apiErr = ErrEventNotification
	case *event.ErrInvalidARN:
		apiErr = ErrARNNotification
	case *event.ErrARNNotFound:
		apiErr = ErrARNNotification
	case *levent.ErrInvalidARN:
		apiErr = ErrLambdaARNInvalid
	case *levent.ErrARNNotFound:
		apiErr = ErrLambdaARNNotFound
	case *event.ErrUnknownRegion:
		apiErr = ErrRegionNotification

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_py39.py hl[8] *}

Эти функции можно объявить с `async def` или обычным `def`.

### Событие `startup` { #startup-event }

Чтобы добавить функцию, которую нужно запустить до старта приложения, объявите её как обработчик события `"startup"`:

{* ../../docs_src/events/tutorial001_py39.py hl[8] *}

Essas funções podem ser declaradas com `async def` ou `def` normal.

### Evento `startup` { #startup-event }

Para adicionar uma função que deve rodar antes de a aplicação iniciar, declare-a com o evento `"startup"`:

{* ../../docs_src/events/tutorial001_py39.py hl[8] *}

Nesse caso, a função de manipulador do evento `startup` inicializará os itens do "banco de dados" (apenas um `dict`) com alguns valores.

	UserAgent    string
}

// ToEvent - converts to notification event.
func (args eventArgs) ToEvent(escape bool) event.Event {
	eventTime := UTCNow()
	uniqueID := fmt.Sprintf("%X", eventTime.UnixNano())
	if !args.Object.ModTime.IsZero() {
		uniqueID = fmt.Sprintf("%X", args.Object.ModTime.UnixNano())
	}

	respElements := map[string]string{
		"x-amz-request-id": args.RespElements["requestId"],

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"`:

首先要注意的是，我们定义了一个带有 `yield` 的异步函数。这与带有 `yield` 的依赖项非常相似。

```Python hl_lines="14-19"
{!../../docs_src/events/tutorial003.py!}
```

这个函数在 `yield`之前的部分，会在应用启动前执行。

剩下的部分在 `yield` 之后，会在应用完成后执行。

## 异步上下文管理器

如你所见，这个函数有一个装饰器 `@asynccontextmanager` 。

它将函数转化为所谓的“**异步上下文管理器**”。

```Python hl_lines="1  13"
{!../../docs_src/events/tutorial003.py!}
```

在 Python 中，  **上下文管理器**是一个你可以在 `with` 语句中使用的东西，例如，`open()` 可以作为上下文管理器使用。