{* ../../docs_src/header_params/tutorial002_an_py310.py hl[10] *}

/// warning | Alertes

Avant de définir `convert_underscores` sur `False`, gardez à l'esprit que certains proxies et serveurs HTTP interdisent l'utilisation d'en-têtes contenant des traits bas.

///

## Gérer les en-têtes dupliqués { #duplicate-headers }

{* ../../docs_src/header_params/tutorial002_an_py310.py hl[10] *}

/// warning | Atenção

Antes de definir `convert_underscores` como `False`, lembre-se de que alguns proxies e servidores HTTP não permitem o uso de cabeçalhos com sublinhados.

///

## Cabeçalhos duplicados { #duplicate-headers }

É possível receber cabeçalhos duplicados. Isso significa, o mesmo cabeçalho com vários valores.

 * connection the client has many options:
 *
 *  * **HTTP proxy:** a proxy server may be explicitly configured for the client. Otherwise, the
 *    [proxy selector][java.net.ProxySelector] is used. It may return multiple proxies to attempt.
 *  * **IP address:** whether connecting directly to an origin server or a proxy, opening a socket
 *    requires an IP address. The DNS server may return multiple IP addresses to attempt.
 *

## What we expect from contributors

1. **Understand the content you submit, PRs as well as issues, and be able to explain it.** Our goal is for humans to use AI tools intentionally and with full control, rather than merely serving as proxies for AI agents. If you cannot explain the reason for something, we will assume you do not understand it, and the PR or issue will likely be closed.

{* ../../docs_src/header_param_models/tutorial003_an_py310.py hl[19] *}

/// warning | Advertencia

Antes de establecer `convert_underscores` a `False`, ten en cuenta que algunos proxies y servidores HTTP no permiten el uso de headers con guiones bajos.

///

## Resumen { #summary }

{* ../../docs_src/header_param_models/tutorial003_an_py310.py hl[19] *}

/// warning | Atenção

Antes de definir `convert_underscores` como `False`, tenha em mente que alguns proxies e servidores HTTP não permitem o uso de cabeçalhos com sublinhados.

///

## Resumo { #summary }

{* ../../docs_src/header_params/tutorial002_an_py310.py hl[10] *}

/// warning

Before setting `convert_underscores` to `False`, bear in mind that some HTTP proxies and servers disallow the usage of headers with underscores.

///

## Duplicate headers { #duplicate-headers }

It is possible to receive duplicate headers. That means, the same header with multiple values.

Uvicorn will expect the proxy to access Uvicorn at `http://127.0.0.1:8000/app`, and then it would be the proxy's responsibility to add the extra `/api/v1` prefix on top.

## About proxies with a stripped path prefix { #about-proxies-with-a-stripped-path-prefix }

Keep in mind that a proxy with stripped path prefix is only one of the ways to configure it.

			// Only grab the first (client) address. Note that '192.168.0.1,
			// 10.1.1.1' is a valid key for X-Forwarded-For where addresses after
			// the first may represent forwarding proxies earlier in the chain.
			s := strings.Index(fwd, ", ")
			if s == -1 {
				s = len(fwd)
			}
			addr = fwd[:s]
		}
	}

	if addr == "" {
		if fwd := r.Header.Get(xRealIP); fwd != "" {

Uvicorn esperará que el proxy acceda a Uvicorn en `http://127.0.0.1:8000/app`, y luego será responsabilidad del proxy añadir el prefijo extra `/api/v1` encima.

## Sobre proxies con un prefijo de path eliminado { #about-proxies-with-a-stripped-path-prefix }

Ten en cuenta que un proxy con prefijo de path eliminado es solo una de las formas de configurarlo.