Err string
}

func (e BackendDown) Error() string {
	return e.Err
}

// NotImplemented If a feature is not implemented
type NotImplemented struct {
	Message string
}

func (e NotImplemented) Error() string {
	return e.Message
}

// UnsupportedMetadata - unsupported metadata
type UnsupportedMetadata struct{}

func (e UnsupportedMetadata) Error() string {

{!../../docs_src/handling_errors/tutorial003.py!}

```

请求 `/unicorns/yolo` 时，路径操作会触发 `UnicornException`。

但该异常将会被 `unicorn_exception_handler` 处理。

接收到的错误信息清晰明了，HTTP 状态码为 `418`，JSON 内容如下：

```JSON
{"message": "Oops! yolo did something. There goes a rainbow..."}

```

/// note | "技术细节"

`from starlette.requests import Request` 和 `from starlette.responses import JSONResponse` 也可以用于导入 `Request` 和 `JSONResponse`。

```Python hl_lines="18  21  23"
{!../../docs_src/path_params/tutorial005.py!}
```

No seu cliente você vai obter uma resposta JSON como:

```JSON
{
  "model_name": "alexnet",
  "message": "Deep Learning FTW!"
}
```

## Parâmetros de rota que contém caminhos

Digamos que você tenha uma *operação de rota* com uma rota `/files/{file_path}`.

	conn := client.gridConn()
	if conn == nil {
		return nil
	}

	_, err := reloadSiteReplicationConfigRPC.Call(ctx, conn, grid.NewMSS())
	return err
}

// VerifyBinary - sends verify binary message to remote peers.
func (client *peerRESTClient) VerifyBinary(ctx context.Context, u *url.URL, sha256Sum []byte, releaseInfo string, reader io.Reader) error {
	values := make(url.Values)
	values.Set(peerRESTURL, u.String())

* etcd: stop watcher when watch channel is closed ([#33003](https://github.com/kubernetes/kubernetes/pull/33003), [@hongchaodeng](https://github.com/hongchaodeng))
* etcd3: dereference the UID pointer for a readable error message. ([#33349](https://github.com/kubernetes/kubernetes/pull/33349), [@madhusudancs](https://github.com/madhusudancs))

    public int size() {
      return IntMath.saturatedAdd(rest.length, 1);
    }

    @Override
    @ParametricNullness
    public E get(int index) {
      // check explicitly so the IOOBE will have the right message
      checkElementIndex(index, size());
      return (index == 0) ? first : rest[index - 1];
    }

    @J2ktIncompatible private static final long serialVersionUID = 0;
  }

			continue
		}
		if ok {
			reply = l.removeEntry(resource, args, &lri) || reply
		}
	}
	return
}

// removeEntry based on the uid of the lock message, removes a single entry from the
// lockRequesterInfo array or the whole array from the map (in case of a write lock
// or last read lock)
// UID and optionally owner must match for entries to be deleted.

                /* Some pipes may require that the hostname in the tree connect
                 * be the netbios name. So if we have the netbios server name
                 * from the NTLMSSP type 2 message, and the share is IPC$, we
                 * assert that the tree connect path uses the netbios hostname.
                 */
                tcax.path = "\\\\" + netbiosName + "\\IPC$";
            }
        }

### Перевірте

Відкрийте браузер та введіть адресу <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

Ви побачите у відповідь таке повідомлення у форматі JSON:

```JSON
{"message": "Hello World"}
```

### Інтерактивна API документація

Перейдемо сюди <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

 *       public void finalizeReferent() {
 *         references.remove(this):
 *         if (!serverSocket.isClosed()) {
 *           ...log a message about how nobody called close()...
 *           try {
 *             serverSocket.close();
 *           } catch (IOException e) {
 *             ...
 *           }
 *         }
 *       }
 *     };