## Proxy Forwarded Headers { #proxy-forwarded-headers }

When using a proxy to handle HTTPS, your **application server** (for example Uvicorn via FastAPI CLI) doesn't known anything about the HTTPS process, it communicates with plain HTTP with the **TLS Termination Proxy**.

package com.google.common.collect.testing;

import static com.google.common.collect.testing.testers.CollectionSpliteratorTester.getSpliteratorNotImmutableCollectionAllowsAddMethod;
import static com.google.common.collect.testing.testers.CollectionSpliteratorTester.getSpliteratorNotImmutableCollectionAllowsRemoveMethod;
import static com.google.common.collect.testing.testers.ListListIteratorTester.getListIteratorFullyModifiableMethod;

    return out
  }

  private fun sendHeaderFrames(
    outFinished: Boolean,
    headers: List<Header>,
  ): Buffer {
    val out = Buffer()
    Http2Writer(out, true).headers(outFinished, expectedStreamId, headers)
    return out
  }

  private fun sendPushPromiseFrames(
    streamId: Int,
    headers: List<Header>,
  ): Buffer {
    val out = Buffer()

import com.google.common.collect.ImmutableMap;
import com.google.common.collect.testing.testers.TestExceptions.SomeCheckedException;
import com.google.common.collect.testing.testers.TestExceptions.SomeError;
import com.google.common.collect.testing.testers.TestExceptions.SomeOtherCheckedException;
import com.google.common.collect.testing.testers.TestExceptions.SomeUncheckedException;
import com.google.errorprone.annotations.CanIgnoreReturnValue;

    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(convert_underscores=False)):

client = TestClient(app)


def test_security_oauth2():
    response = client.get("/users/me", headers={"Authorization": "Bearer footokenbar"})
    assert response.status_code == 200, response.text
    assert response.json() == {"username": "Bearer footokenbar"}


def test_security_oauth2_password_other_header():
    response = client.get("/users/me", headers={"Authorization": "Other footokenbar"})
    assert response.status_code == 200, response.text

    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(convert_underscores=False)],
):

    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: Annotated[CommonHeaders, Header()]):

Este **proxy** normalmente configuraría algunos headers HTTP sobre la marcha antes de transmitir el request al **servidor de aplicaciones**, para hacerle saber al servidor de aplicaciones que el request está siendo **reenviado** por el proxy.

/// note | Detalles técnicos

Los headers del proxy son:

client = TestClient(app)


def test_security_oauth2():
    response = client.get("/users/me", headers={"Authorization": "Bearer footokenbar"})
    assert response.status_code == 200, response.text
    assert response.json() == {"username": "Bearer footokenbar"}


def test_security_oauth2_password_other_header():
    response = client.get("/users/me", headers={"Authorization": "Other footokenbar"})
    assert response.status_code == 200, response.text