* O **FastAPI** adiciona aqui a referência dos esquemas JSON globais que estão localizados em outro lugar, ao invés de incluí-lo diretamente. Deste modo, outras aplicações e clientes podem utilizar estes esquemas JSON diretamente, fornecer melhores ferramentas de geração de código, etc.

///

O retorno gerado no OpenAPI para esta *operação de rota* será:

```JSON hl_lines="3-12"
{

Pero es posible personalizarlo, puedes establecer un CDN específico, o servir los archivos tú mismo.

## CDN Personalizado para JavaScript y CSS { #custom-cdn-for-javascript-and-css }

El usuario de tu API (un desarrollador externo) creará una factura en tu API con un request POST.

Luego tu API (imaginemos):

* Enviará la factura a algún cliente del desarrollador externo.
* Recogerá el dinero.
* Enviará una notificación de vuelta al usuario de la API (el desarrollador externo).

Mas é possível personalizá-los, você pode definir um CDN específico ou providenciar os arquivos você mesmo.

## CDN Personalizado para JavaScript e CSS { #custom-cdn-for-javascript-and-css }

### CVE-2022-3172: Aggregated API server can cause clients to be redirected (SSRF)

A security issue was discovered in kube-apiserver that could allow an attacker controlled aggregated API server to redirect client traffic to any URL.  This could lead to the client performing unexpected actions as well as leaking the client's credentials to third parties. 

OkHttp includes a library for testing HTTP, HTTPS, and HTTP/2 clients.

The latest release is available on [Maven Central](https://search.maven.org/artifact/com.squareup.okhttp3/mockwebserver/5.3.0/jar).

```kotlin
testImplementation("com.squareup.okhttp3:mockwebserver3:5.3.0")
```

MockWebServer is used for firstly for internal testing, and for basic testing of apps using OkHttp client.

	// accordingly. Client receives a HTTP error for invalid/unsupported
	// signatures.
	//
	// Validates all incoming requests to have a valid date header.
	setAuthMiddleware,
	// Redirect some pre-defined browser request paths to a static location
	// prefix.
	setBrowserRedirectMiddleware,
	// Adds 'crossdomain.xml' policy middleware to serve legacy flash clients.
	setCrossDomainPolicyMiddleware,

			return
		}
		h.ServeHTTP(w, r)
	})
}

// addCustomHeadersMiddleware adds various HTTP(S) response headers.
// Security Headers enable various security protections behaviors in the client's browser.
func addCustomHeadersMiddleware(h http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		header := w.Header()

### Required, can be `None` { #required-can-be-none }

You can declare that a parameter can accept `None`, but that it's still required. This would force clients to send a value, even if the value is `None`.

To do that, you can declare that `None` is a valid type but simply do not declare a default value:

	// MinIO verifies the client certificate present by the client
	// when requesting temp. credentials.
	// By default, MinIO always verify the client certificate.
	//
	// The client certificate verification should only be skipped
	// when debugging or testing a setup since it allows arbitrary
	// clients to obtain temp. credentials with arbitrary policy