Starlette (and **FastAPI**) are based on <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a>, which makes it compatible with both Python's standard library <a href="https://docs.python.org/3/library/asyncio-task.html" class="external-link" target="_blank">asyncio</a> and <a href="https://trio.readthedocs.io/en/stable/" class="external-link" target="_blank">Trio</a>.

Here we'll see an example using <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a>.

**SQLModel** is built on top of <a href="https://www.sqlalchemy.org/" class="external-link" target="_blank">SQLAlchemy</a> and Pydantic. It was made by the same author of **FastAPI** to be the perfect match for FastAPI applications that need to use **SQL databases**.

Hier werden wir ein Beispiel mit <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a> sehen.

adicionados <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">usando o prefixo `X-`</a>.

Porém, se voce tiver cabeçalhos personalizados que deseja que um cliente no navegador possa ver, você precisa adicioná-los às suas configurações de CORS (saiba mais em [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), usando o parâmetro `expose_headers` descrito na <a href="https://www.starlette.dev/middle...

# CORS (Cross-Origin Resource Sharing) { #cors-cross-origin-resource-sharing }

<a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS" class="external-link" target="_blank">CORS or "Cross-Origin Resource Sharing"</a> refers to the situations when a frontend running in a browser has JavaScript code that communicates with a backend, and the backend is in a different "origin" than the frontend.

## Origin { #origin }

/// tip

This section is useful only to a handful of people, team members with permissions to manage the repository. You can probably skip it. 😉

///

...so, you are a [team member of FastAPI](./fastapi-people.md#team){.internal-link target=_blank}? Wow, you are so cool! 😎

* <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>

///

        assertEquals("url cannot be null", e.getMessage());
    }

    @Test
    void testGetInputStream() throws Exception {
        URL txtFile = new File("target/test-classes/source.txt").toURI().toURL();
        UrlSource source = new UrlSource(txtFile);
        try (InputStream is = source.getInputStream();
                Scanner scanner = new Scanner(is)) {

You can read more about this in the [Advanced User Guide](../advanced/index.md){.internal-link target=_blank}.

## Details { #details }

The first `"/static"` refers to the sub-path this "sub-application" will be "mounted" on. So, any path that starts with `"/static"` will be handled by it.

Puedes leer más sobre esto en la [Guía de Usuario Avanzada](../advanced/index.md){.internal-link target=_blank}.

## Detalles { #details }

El primer `"/static"` se refiere al sub-path en el que esta "sub-aplicación" será "montada". Por lo tanto, cualquier path que comience con `"/static"` será manejado por ella.