from enum import Enum

from fastapi import FastAPI


class ModelName(str, Enum):
    alexnet = "alexnet"
    resnet = "resnet"
    lenet = "lenet"


app = FastAPI()


@app.get("/models/{model_name}")
async def get_model(model_name: ModelName):
    if model_name is ModelName.alexnet:
        return {"model_name": model_name, "message": "Deep Learning FTW!"}

    if model_name.value == "lenet":

### Erstellen Sie eine `Enum`-Klasse

Importieren Sie `Enum` und erstellen Sie eine Unterklasse, die von `str` und `Enum` erbt.

### Создание класса `Enum`

Импортируйте `Enum` и создайте подкласс, который наследуется от `str` и `Enum`.

Мы наследуемся от `str`, чтобы документация API могла понять, что значения должны быть типа `string` и отображалась правильно.

Qualquer requisição para `http` ou `ws` será redirecionada para o esquema seguro.

{* ../../docs_src/advanced_middleware/tutorial001.py hl[2,6] *}

## `TrustedHostMiddleware`

Garante que todas as requisições recebidas tenham um cabeçalho `Host` corretamente configurado, a fim de proteger contra ataques de cabeçalho de host HTTP.

{* ../../docs_src/advanced_middleware/tutorial002.py hl[2,6:8] *}

Os seguintes argumentos são suportados:

 */
// These benchmarks allocate a lot of data so use a large heap
@VmOptions({"-Xms12g", "-Xmx12g", "-d64"})
public class CharStreamsCopyBenchmark {
  enum CopyStrategy {
    OLD {
      @Override
      long copy(Readable from, Appendable to) throws IOException {
        CharBuffer buf = CharStreams.createBuffer();
        long total = 0;

 */
// These benchmarks allocate a lot of data so use a large heap
@VmOptions({"-Xms12g", "-Xmx12g", "-d64"})
public class CharStreamsCopyBenchmark {
  enum CopyStrategy {
    OLD {
      @Override
      long copy(Readable from, Appendable to) throws IOException {
        CharBuffer buf = CharStreams.createBuffer();
        long total = 0;

  }

  // A static mapping from an Enum type to its set of LockGraphNodes.
  private static final ConcurrentMap<
          Class<? extends Enum<?>>, Map<? extends Enum<?>, LockGraphNode>>
      lockGraphNodesPerType = new MapMaker().weakKeys().makeMap();

  /** Creates a {@code CycleDetectingLockFactory.WithExplicitOrdering<E>}. */
  public static <E extends Enum<E>> WithExplicitOrdering<E> newInstanceWithExplicitOrdering(

```

否则，`/users/{user_id}` 将匹配 `/users/me`，FastAPI 会**认为**正在接收值为 `"me"` 的 `user_id` 参数。

## 预设值

路径操作使用 Python 的 <abbr title="Enumeration">`Enum`</abbr> 类型接收预设的*路径参数*。

### 创建 `Enum` 类

导入 `Enum` 并创建继承自 `str` 和 `Enum` 的子类。

通过从 `str` 继承，API 文档就能把值的类型定义为**字符串**，并且能正确渲染。

然后，创建包含固定值的类属性，这些固定值是可用的有效值：

```Python hl_lines="1  6-9"
{!../../docs_src/path_params/tutorial005.py!}

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.hash;


/**
 * An enum that contains all of the known hash functions.
 *
 * @author Kurt Alfred Kluever
 */
enum HashFunctionEnum {
  ADLER32(Hashing.adler32()),
  CRC32(Hashing.crc32()),
  GOOD_FAST_HASH_32(Hashing.goodFastHash(32)),
  GOOD_FAST_HASH_64(Hashing.goodFastHash(64)),

### Bir `Enum` Sınıfı Oluşturalım

`Enum` sınıfını projemize dahil edip `str` ile `Enum` sınıflarını miras alan bir alt sınıf yaratalım.