Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

///

## Optionaler Datei-Upload { #optional-file-upload }

Sie können eine Datei optional machen, indem Sie Standard-Typannotationen verwenden und den Defaultwert auf `None` setzen:

{* ../../docs_src/request_files/tutorial001_02_an_py310.py hl[9,17] *}

   * Predicates.notNull())}, static importing as necessary.
   *
   * <p><b>Note:</b> if {@code first} is represented as an {@link Optional}, this can be
   * accomplished with {@link Optional#or(Object) first.or(second)}. That approach also allows for
   * lazy evaluation of the fallback instance, using {@link Optional#or(Supplier)
   * first.or(supplier)}.
   *
   * <p><b>Java 9 users:</b> use {@code java.util.Objects.requireNonNullElse(first, second)}

```
is optional and can be used to specify additional attributes to lookup on the User DN record in the LDAP server. This is for certain display purposes and may be used for extended functionality that may be added in the future.

### Group membership search

MinIO can be optionally configured to find the groups of a user from AD/LDAP by specifying the following variables:

```

////

#### Uso de `Union` u `Optional` { #using-union-or-optional }

Si estás usando una versión de Python inferior a 3.10, aquí tienes un consejo desde mi punto de vista muy **subjetivo**:

* 🚨 Evita usar `Optional[SomeType]`
* En su lugar ✨ **usa `Union[SomeType, None]`** ✨.

import org.apache.logging.log4j.Logger;

/**
 * A thread that reads from an input stream line by line and maintains a buffer of recent lines.
 * This class provides functionality to read input stream data asynchronously,
 * optionally process each line with a callback function, and maintain a circular buffer
 * of recent lines for retrieval.
 */
public class InputStreamThread extends Thread {
    /** Logger instance for this class */

	// Cached values:
	pathString         string
	strippedTableAlias string
	strippedPathExpr   []*JSONPathElement
}

// AliasedExpression is an expression that can be optionally named
type AliasedExpression struct {
	Expression *Expression `parser:"@@"`
	As         string      `parser:"[ \"AS\" @Ident | \"AS\" @LitString ]"`
}

// Grammar for Expression
//

{* ../../docs_src/body_nested_models/tutorial007_py310.py hl[7,12,18,21,25] *}

/// info | Info

Beachten Sie, wie `Offer` eine Liste von `Item`s hat, die ihrerseits eine optionale Liste von `Image`s haben.

///

## Bodys aus reinen Listen { #bodies-of-pure-lists }

Si no deseas incluir las dependencias opcionales `standard`, puedes instalar con `pip install fastapi` en lugar de `pip install "fastapi[standard]"`.

### Sin `fastapi-cloud-cli` { #without-fastapi-cloud-cli }

Si quieres instalar FastAPI con las dependencias standard pero sin `fastapi-cloud-cli`, puedes instalar con `pip install "fastapi[standard-no-fastapi-cloud-cli]"`.

### Dependencias Opcionales Adicionales { #additional-optional-dependencies }

You could also use it to generate code automatically, for clients that communicate with your API. For example, frontend, mobile or IoT applications.

### Deploy your app (optional) { #deploy-your-app-optional }

You can optionally deploy your FastAPI app to <a href="https://fastapicloud.com" class="external-link" target="_blank">FastAPI Cloud</a>, go and join the waiting list if you haven't. 🚀

    * **WebSockets**
    * extremely easy tests based on HTTPX and `pytest`
    * **CORS**
    * **Cookie Sessions**
    * ...and more.

### Deploy your app (optional) { #deploy-your-app-optional }

You can optionally deploy your FastAPI app to <a href="https://fastapicloud.com" class="external-link" target="_blank">FastAPI Cloud</a>, go and join the waiting list if you haven't. 🚀