"/items/1",
        json={
            "title": "Foo",
            "timestamp": "2023-01-01T12:00:00",
            "description": "A test item",
        },
    )
    assert response.status_code == 200, response.text
    assert response.json() == {
        "description": "A test item",
        "timestamp": "2023-01-01T12:00:00",
        "title": "Foo",
    }


def test_openapi_schema_pv2(client: TestClient):

        json={
            "title": "Foo",
            "timestamp": "2023-01-01T12:00:00",
            "description": "An optional description",
        },
    )
    assert response.status_code == 200
    assert "123" in fake_db
    assert fake_db["123"] == {
        "title": "Foo",
        "timestamp": "2023-01-01T12:00:00",
        "description": "An optional description",
    }

```

</div>

então a variável interna `__name__` no seu arquivo, criada automaticamente pelo Python, terá como valor a string `"__main__"`.

Então, a seção:

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

vai executar.

---

Isso não acontecerá se você importar esse módulo (arquivo).

Então, se você tiver outro arquivo `importer.py` com:

```Python
from myapp import app

```

</div>

dann hat in Ihrer Datei die interne Variable `__name__`, die von Python automatisch erstellt wird, als Wert den String `"__main__"`.

Daher wird der Abschnitt:

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

ausgeführt.

---

Dies wird nicht passieren, wenn Sie das Modul (die Datei) importieren.

Wenn Sie also eine weitere Datei `importer.py` mit folgendem Inhalt haben:

```Python

import uvicorn
from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def root():
    a = "a"
    b = "b" + a
    return {"hello world": b}


if __name__ == "__main__":

```

</div>

then the internal variable `__name__` in your file, created automatically by Python, will have as value the string `"__main__"`.

So, the section:

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

will run.

---

This won't happen if you import that module (file).

So, if you have another file `importer.py` with:

```Python
from myapp import app

# Some more code

    with unittest.mock.patch("uvicorn.run") as uvicorn_run_mock:
        runpy.run_module(MOD_NAME, run_name="__main__")

    uvicorn_run_mock.assert_called_once_with(
        unittest.mock.ANY, host="0.0.0.0", port=8000
    )


def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")
    assert response.status_code == 200
    assert response.json() == {
        "openapi": "3.1.0",

Si instalaste un servidor ASGI manualmente, normalmente necesitarías pasar una cadena de import en un formato especial para que importe tu aplicación FastAPI:

<div class="termy">

```console
$ uvicorn main:app --host 0.0.0.0 --port 80

<span style="color: green;">INFO</span>:     Uvicorn running on http://0.0.0.0:80 (Press CTRL+C to quit)
```

</div>

/// note | Nota

El comando `uvicorn main:app` se refiere a:

graph LR

browser("Browser")
proxy["Proxy on http://0.0.0.0:9999/api/v1/app"]
server["Server on http://127.0.0.1:8000/app"]

browser --> proxy
proxy --> server
```

/// tip

The IP `0.0.0.0` is commonly used to mean that the program listens on all the IPs available in that machine/server.

///

## `fastapi run` { #fastapi-run }

Ejecutar `fastapi run` inicia FastAPI en modo de producción por defecto.