* Valider que `item_id` existe dans le chemin des requêtes `GET` et `PUT`.
* Valider que `item_id` est de type `int` pour les requêtes `GET` et `PUT`.
    * Si ce n'est pas le cas, le client voit une erreur utile et claire.
* Vérifier qu'il existe un paramètre de requête facultatif nommé `q` (comme dans `http://127.0.0.1:8000/items/foo?q=somequery`) pour les requêtes `GET`.
    * Puisque le paramètre `q` est déclaré avec `= None`, il est facultatif.

    - 數據模型
    - ...還有其他更多
- 自動生成的 API 文件，包含 2 種不同的使用介面：
    - Swagger UI
    - ReDoc

---

回到前面的的程式碼範例，**FastAPI** 還會：

- 驗證 `GET` 和 `PUT` 請求路徑中是否包含 `item_id`。
- 驗證 `GET` 和 `PUT` 請求中的 `item_id` 是否是 `int` 型別。
    - 如果驗證失敗，將會返回清楚有用的錯誤訊息。
- 查看 `GET` 請求中是否有命名為 `q` 的查詢參數 (例如 `http://127.0.0.1:8000/items/foo?q=somequery`)。
    - 因為 `q` 參數被宣告為 `= None`，所以是選填的。
    - 如果沒有宣告 `None`，則此參數將會是必填 (例如 `PUT` 範例的請求 body)。

        exceptions.add(e);

        return this;
    }

    public OverConstrainedVersionException getVersionRangeViolation(int i) {
        return (OverConstrainedVersionException) versionRangeViolations.get(i);
    }

    public List<Exception> getVersionRangeViolations() {
        return versionRangeViolations == null
                ? Collections.emptyList()

        case -2:
          // requireNonNull is safe because right must exist in order to get a negative factor.
          requireNonNull(right);
          if (right.balanceFactor() > 0) {
            right = right.rotateRight();
          }
          return rotateLeft();
        case 2:
          // requireNonNull is safe because left must exist in order to get a positive factor.
          requireNonNull(left);

			}

			podName, ns := handlers.InferPodInfo(args[0], ctx.NamespaceOrDefault(""))

			client, err := ctx.CLIClient()
			if err != nil {
				return err
			}
			pod, err := client.Kube().CoreV1().Pods(ns).Get(context.TODO(), podName, metav1.GetOptions{})
			if err != nil {
				return err
			}

			writer := cmd.OutOrStdout()

			podLabels := klabels.Set(pod.ObjectMeta.Labels)

    public boolean containsValue(Object value) {
      assertTrue(Thread.holdsLock(mutex));
      return super.containsValue(value);
    }

    @Override
    public @Nullable V get(Object key) {
      assertTrue(Thread.holdsLock(mutex));
      return super.get(key);
    }

    @Override
    public @Nullable V put(K key, V value) {
      assertTrue(Thread.holdsLock(mutex));
      return super.put(key, value);
    }

    Predicate<Throwable> predicate = INSTANCE_OF.get(expectedThrowable);
    if (predicate == null) {
      throw new IllegalArgumentException(
          expectedThrowable
              + " is not yet supported by ReflectionFreeAssertThrows. Add an entry for it in the"
              + " map in that class.");
    }
    Object result;
    try {
      result = supplier.get();
    } catch (Throwable t) {

    return backingMap;
  }

  @SuppressWarnings("unchecked") // value could not get in if not a T
  @CheckForNull
  private <T extends B> T trustedPut(TypeToken<@NonNull T> type, @ParametricNullness T value) {
    return (T) backingMap.put(type, value);
  }

  @SuppressWarnings("unchecked") // value could not get in if not a T
  @CheckForNull
  private <T extends @NonNull B> T trustedGet(TypeToken<T> type) {

		Description:    "The web identity token that was passed is expired or is not valid. Get a new identity token from the identity provider and then retry the request.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrSTSClientGrantsExpiredToken: {
		Code:           "ExpiredToken",
		Description:    "The client grants that was passed is expired or is not valid. Get a new client grants token from the identity provider and then retry the request.",

def invoice_notification(body: InvoiceEvent):
    pass  # pragma: nocover


class Event(BaseModel):
    name: str
    total: float


events_callback_router = APIRouter()


@events_callback_router.get("{$callback_url}/events/{$request.body.title}")
def event_callback(event: Event):
    pass  # pragma: nocover


subrouter = APIRouter()


@subrouter.post("/invoices/", callbacks=invoices_callback_router.routes)