assertCollectionSize(map.keySet(), size);
    assertCollectionSize(map.entrySet(), size);
    assertCollectionSize(map.values(), size);
  }

  @SuppressWarnings("IterablesSizeOfCollection") // we are testing our iterator implementation
  private void assertCollectionSize(Collection<?> collection, int size) {
    assertThat(collection.size()).isEqualTo(size);
    if (size > 0) {
      assertThat(collection.isEmpty()).isFalse();

都没关系，**FastAPI** 知道该怎么处理。

/// note | 注意

如果不了解异步，请参阅文档中关于 `async` 和 `await` 的章节：[异步：*“着急了？”*](../../async.md#in-a-hurry)。

///

## 与 OpenAPI 集成 { #integrated-with-openapi }

依赖项及子依赖项中声明的所有请求、验证和需求都会集成到同一个 OpenAPI 模式中。

因此，交互式文档中也会包含这些依赖项的所有信息：

<img src="/img/tutorial/dependencies/image01.png">

## 简单用法 { #simple-usage }

      resetContainer(mapEntry(k0(), v0()), mapEntry(k0(), v1()), mapEntry(k0(), v0()));
      List<V> expectedValues = copyToList(values);

      Entry<K, Collection<V>> asMapEntry = multimap().asMap().entrySet().iterator().next();
      List<V> asMapValue = (List<V>) asMapEntry.getValue();
      asMapValue.remove(i);
      expectedValues.remove(i);

      assertGet(k0(), expectedValues);
    }
  }

  // (In the backport, we don't need this suppression, but we keep it to minimize diffs.)
  @SuppressWarnings("unchecked")
  @Override
  public UnmodifiableIterator<E> iterator() {
    return (UnmodifiableIterator<E>) Iterators.forArray(elements);
  }

  @Override
  public Spliterator<E> spliterator() {
    return Spliterators.spliterator(elements, SPLITERATOR_CHARACTERISTICS);
  }

    assertFalse(list.contains("chicken"));
    assertEquals(-1, list.indexOf("chicken"));
    assertEquals(-1, list.lastIndexOf("chicken"));
  }

  private static <E> Iterator<E> asIterator(E... elements) {
    return asList(elements).iterator();
  }

  // In GWT, java.util.TreeSet throws ClassCastException when the comparator
  // throws it, unlike the JDK.  Therefore, we accept ClassCastException as a

```

`app.add_middleware()` reçoit une classe de middleware en premier argument, ainsi que tout argument supplémentaire à transmettre au middleware.

## Utiliser les middlewares intégrés { #integrated-middlewares }

**FastAPI** inclut plusieurs middlewares pour des cas d'usage courants ; voyons comment les utiliser.

/// note | Détails techniques

        continue
      }

      // Search for the certificate in the chain that signed this certificate. This is typically
      // the next element in the chain, but it could be any element.
      val i = queue.iterator()
      while (i.hasNext()) {
        val signingCert = i.next() as X509Certificate
        if (verifySignature(toVerify, signingCert, result.size - 1)) {
          i.remove()
          result.add(signingCert)

/// note | Remarque

Si vous ne savez pas, consultez la section [Async : *« Pressé ? »*](../../async.md#in-a-hurry) à propos de `async` et `await` dans la documentation.

///

## Intégrer à OpenAPI { #integrated-with-openapi }

Toutes les déclarations de requête, validations et exigences de vos dépendances (et sous-dépendances) seront intégrées dans le même schéma OpenAPI.

import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Nonnull;

/**
 * Transport for specified remote repository (using provided remote repository base URI as root). Must be treated as a
 * resource, best in try-with-resource block.
 *
 * @since 4.0.0
 */
@Experimental
@Consumer
public interface Transport extends Closeable {
    /**

from unicorn import UnicornMiddleware

app = FastAPI()

app.add_middleware(UnicornMiddleware, some_config="rainbow")
```

`app.add_middleware()` 的第一个参数是中间件的类，其它参数则是要传递给中间件的参数。

## 集成中间件 { #integrated-middlewares }

**FastAPI** 为常见用例提供了一些中间件，下面介绍怎么使用这些中间件。

/// note | 技术细节

以下几个示例中也可以使用 `from starlette.middleware.something import SomethingMiddleware`。