### Sobrescribir excepciones de validación de request

Cuando un request contiene datos inválidos, **FastAPI** lanza internamente un `RequestValidationError`.

Y también incluye un manejador de excepciones predeterminado para ello.

Para sobrescribirlo, importa el `RequestValidationError` y úsalo con `@app.exception_handler(RequestValidationError)` para decorar el manejador de excepciones.

### Créalo

* Crea un archivo `main.py` con:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

* Maak het bestand `main.py` aan met daarin:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

### Crie

* Crie um arquivo `main.py` com:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

{* ../../docs_src/custom_response/tutorial009c.py hl[9:14,17] *}

Ahora en lugar de devolver:

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

...este response devolverá:

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

Por supuesto, probablemente encontrarás formas mucho mejores de aprovechar esto que formatear JSON. 😉

## Clase de response predeterminada

    }

    @Test
    void testReadSecurityBuffer() {
        // Test readSecurityBuffer
        byte[] data = new byte[20];
        byte[] content = "Hello".getBytes();

        // Simulate a security buffer structure: length (2 bytes), length (2 bytes), offset (4 bytes)
        // Length = 5, Offset = 8

	if err != nil {
		// Failed to create newbucket, abort.
		t.Fatalf("%s : %s", instanceType, err.Error())
	}

	var (
		nilBytes    []byte
		data        = []byte("hello")
		fiveMBBytes = bytes.Repeat([]byte("a"), 5*humanize.MiByte)
	)
	invalidMD5 := getMD5Hash([]byte("meh"))
	invalidMD5Header := md5Header([]byte("meh"))

	testCases := []struct {
		bucketName    string

- name: full-stack-fastapi-template
  html_url: https://github.com/fastapi/full-stack-fastapi-template
  stars: 37341
  owner_login: fastapi
  owner_html_url: https://github.com/fastapi
- name: Hello-Python
  html_url: https://github.com/mouredev/Hello-Python
  stars: 31799
  owner_login: mouredev
  owner_html_url: https://github.com/mouredev
- name: serve
  html_url: https://github.com/jina-ai/serve
  stars: 21721
  owner_login: jina-ai

    @Test
    public void testEncodingSpecialCharacters() {
        CurlRequest request = new CurlRequest(Method.GET, "https://example.com");

        // Test encoding of special characters
        request.param("query", "hello world & more");
        request.param("special", "ñ€±");

        // Should not throw exception
        assertNotNull(request);
    }

    @Test
    public void testUnsupportedEncodingThrowsException() {