user  nginx;
worker_processes  auto;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

events {
    worker_connections  4096;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '

                    isActive &= activator.isActive(profile, context, problems);
                }
            } catch (RuntimeException e) {
                problems.add(new ModelProblemCollectorRequest(Severity.ERROR, Version.BASE)
                        .setMessage(
                                "Failed to determine activation for profile " + profile.getId() + ": " + e.getMessage())

        }
    ]
}
```

将得到如下文本内容：

```
Validation errors:
Field: ('path', 'item_id'), Error: Input should be a valid integer, unable to parse string as an integer
```

### 覆盖 `HTTPException` 错误处理器 { #override-the-httpexception-error-handler }

同理，也可以覆盖 `HTTPException` 的处理器。

例如，只为这些错误返回纯文本响应，而不是 JSON：

user  nginx;
worker_processes  auto;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

events {
    worker_connections  4096;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '

                    "schema": {
                        "$ref": "#/components/schemas/Item"
                    }
                }
            }
        },
        "422": {
            "description": "Validation Error",
            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/HTTPValidationError"
                    }
                }

                    "schema": {
                        "$ref": "#/components/schemas/Item"
                    }
                }
            }
        },
        "422": {
            "description": "Validation Error",
            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/HTTPValidationError"
                    }
                }

			endpoints, secure, err := parseEndpoints(testCase.s)
			if err != nil && testCase.success {
				t.Errorf("expected to succeed but failed with %s", err)
			}
			if !testCase.success && err == nil {
				t.Error("expected failure but succeeded instead")
			}
			if testCase.success {
				if !reflect.DeepEqual(endpoints, testCase.endpoints) {
					t.Errorf("expected %s, got %s", testCase.endpoints, endpoints)
				}

    print(f"Hey {name}!")
```

El parámetro `name` está definido como `Optional[str]`, pero **no es opcional**, no puedes llamar a la función sin el parámetro:

```Python
say_hi()  # ¡Oh, no, esto lanza un error! 😱
```

El parámetro `name` **sigue siendo requerido** (no es *opcional*) porque no tiene un valor por defecto. Aun así, `name` acepta `None` como valor:

```Python
say_hi(name=None)  # Esto funciona, None es válido 🎉

  val size: Int
    get() = encodedNames.size

  @JvmName("-deprecated_size")
  @Deprecated(
    message = "moved to val",
    replaceWith = ReplaceWith(expression = "size"),
    level = DeprecationLevel.ERROR,
  )
  fun size(): Int = size

  fun encodedName(index: Int): String = encodedNames[index]

  fun name(index: Int): String = encodedName(index).percentDecode(plusIsSpace = true)

                    "schema": {
                        "$ref": "#/components/schemas/Item"
                    }
                }
            }
        },
        "422": {
            "description": "Validation Error",
            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/HTTPValidationError"
                    }
                }