*/
    @JvmField
    val FORCE_CACHE = commonForceCache()

    /**
     * Returns the cache directives of [headers]. This honors both Cache-Control and Pragma headers
     * if they are present.
     */
    @JvmStatic
    fun parse(headers: Headers): CacheControl = commonParse(headers)
  }

Mas, por segurança, como o servidor não sabe que está atrás de um proxy confiável, ele não interpretará esses headers.

/// note | Detalhes Técnicos

Os headers do proxy são:

def test_security_http_basic_invalid_credentials():
    response = client.get(
        "/users/me", headers={"Authorization": "Basic notabase64token"}
    )
    assert response.status_code == 401, response.text
    assert response.headers["WWW-Authenticate"] == "Basic"
    assert response.json() == {"detail": "Not authenticated"}


def test_security_http_basic_non_basic_credentials():

}

// TestExtractSignedHeaders - Tests validate extraction of signed headers using list of signed header keys.
func TestExtractSignedHeaders(t *testing.T) {
	signedHeaders := []string{"host", "x-amz-content-sha256", "x-amz-date", "transfer-encoding"}

	// If the `expect` key exists in the signed headers then golang server would have stripped out the value, expecting the `expect` header set to `100-continue` in the result.

    response = client.get("/users/me", headers={"Authorization": "Bearer nonexistent"})
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "Bearer"


def test_incorrect_token_type(client: TestClient):
    response = client.get(
        "/users/me", headers={"Authorization": "Notexistent testtoken"}
    )

## Headers reenviados por el proxy { #proxy-forwarded-headers }

Al usar un proxy para gestionar HTTPS, tu **servidor de aplicaciones** (por ejemplo Uvicorn vía FastAPI CLI) no sabe nada sobre el proceso HTTPS, se comunica con HTTP simple con el **TLS Termination Proxy**.

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: Annotated[CommonHeaders, Header()]):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: Union[str, None] = None
    traceparent: Union[str, None] = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: CommonHeaders = Header()):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: CommonHeaders = Header()):

* <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/X-Forwarded-Proto" class="external-link" target="_blank">X-Forwarded-Proto</a>
* <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/X-Forwarded-Host" class="external-link" target="_blank">X-Forwarded-Host</a>

///

### Proxy-Forwarded-Header aktivieren { #enable-proxy-forwarded-headers }