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] *}

import org.openjdk.jmh.annotations.Threads;
import org.openjdk.jmh.annotations.Warmup;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.TimeUnit;
import java.util.function.Function;

/**
 * Benchmarks the overhead of constructing {@link Aggregator}s in many

            VersionRange versionRange,
            String type,
            String classifier,
            String scope,
            boolean optional) {
        return createArtifactX(groupId, artifactId, versionRange, type, classifier, scope, null, optional);
    }

    private Artifact createProjectArtifactX(String groupId, String artifactId, String version) {

# ----------------------------------------------------------------------------

# ----------------------------------------------------------------------------
# Apache Maven Wrapper startup batch script, version 3.3.4
#
# Optional ENV vars
# -----------------
#   JAVA_HOME - location of a JDK home dir, required when download maven via java source
#   MVNW_REPOURL - repo url base for downloading maven distribution

        Class<?> processHandleInfoClass = Class.forName("java.lang.ProcessHandle$Info");
        Class<?> optionalClass = Class.forName("java.util.Optional");
        /*
         * We don't *need* to use reflection to access Optional: It's available on all JDKs we
         * support, and Android code won't get this far, anyway, because ProcessHandle is

							jcifs*;version="${osgi.pkg.version}",
						</Export-Package>
						<Private-Package />
						<Import-Package>
							jakarta.servlet*;resolution:=optional,
							com.sun.security.jgss;resolution:=optional,
							org.bouncycastle*;version="1.63",
							!jcifs.internal*,
							*
						</Import-Package>
					</instructions>
				</configuration>
			</plugin>
			<plugin>

///

## Zusätzliche Validierung { #additional-validation }

Wir werden sicherstellen, dass, obwohl `q` optional ist, wann immer es bereitgestellt wird, **seine Länge 50 Zeichen nicht überschreitet**.

### `Query` und `Annotated` importieren { #import-query-and-annotated }

Um dies zu erreichen, importieren Sie zuerst:

   * dependence on a type/method which GWT doesn't support, it is sufficient to simply reference the
   * unsupported type/method. E.g. "Class.isInstance".
   *
   * <p>As of Guava 20.0, this value is optional. We encourage authors who wish to describe why an
   * API is {@code @GwtIncompatible} to instead leave an implementation comment.
   */
  String value() default "";

s=b(require("jquery")):b(a.jQuery)}(this,function(a){!function(a,b,c){"use strict";function d(b,c,d){var e=!0;return b.find("[data-validation]").each(function(){if(this!==c){var b=a(this),f=b.hasClass(d.successElementClass),g="true"===b.valAttr("optional"),h=b.hasClass(d.errorElementClass);if(h||!f&&!g)return e=!1,!1}}),e}a.formUtils.registerLoadedModule("toggleDisabled");var e=function(a,b){"disabled"===b?a.find('*[type="submit"]').addClass("disabled").attr("disabled","disabled"):a.find('*[type...

import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Map;
import java.util.Set;

/**
 * Optional features of classes derived from {@code Map}.
 *
 * @author George van den Driessche
 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible