silver:
  - url: https://databento.com/?utm_source=fastapi&utm_medium=sponsor&utm_content=display
    title: Pay as you go for market data
    img: https://fastapi.tiangolo.com/img/sponsors/databento.svg
  - url: https://speakeasy.com/editor?utm_source=fastapi+repo&utm_medium=github+sponsorship
    title: SDKs for your API | Speakeasy
    img: https://fastapi.tiangolo.com/img/sponsors/speakeasy.png
  - url: https://www.svix.com/

{* ../../docs_src/path_params/tutorial002_py310.py hl[7] *}

En este caso, `item_id` se declara como un `int`.

/// check | Revisa

Esto te dará soporte del editor dentro de tu función, con chequeo de errores, autocompletado, etc.

///

## <dfn title="también conocido como: serialización, parsing, marshalling">Conversión</dfn> de datos { #data-conversion }

{* ../../docs_src/path_params/tutorial002_py310.py hl[7] *}

In this case, `item_id` is declared to be an `int`.

/// check

This will give you editor support inside of your function, with error checks, completion, etc.

///

## Data <dfn title="also known as: serialization, parsing, marshalling">conversion</dfn> { #data-conversion }

* `headers` - Eklenecek özel header’lar; dictionary olarak.
* `media_type` - Media type’ı veren string. Ayarlanmazsa, dosya adı veya path kullanılarak media type tahmin edilir.
* `filename` - Ayarlanırsa response içindeki `Content-Disposition`’a dahil edilir.

File response'ları uygun `Content-Length`, `Last-Modified` ve `ETag` header’larını içerir.

{* ../../docs_src/custom_response/tutorial009_py310.py hl[2,10] *}

Die gleichen Prozesse, die für Pfad-Parameter gelten, werden auch auf Query-Parameter angewendet:

* Editor Unterstützung (natürlich)
* Daten-<dfn title="Konvertieren des Strings, der von einem HTTP-Request kommt, in Python-Daten">„Parsen“</dfn>
* Datenvalidierung
* Automatische Dokumentation

## Defaultwerte { #defaults }

/// note | Nota

FastAPI sabrá que el valor de `q` no es requerido por el valor por defecto `= None`.

Tener `str | None` permitirá que tu editor te dé un mejor soporte y detecte errores.

///

## Validaciones adicionales { #additional-validation }

Vamos a hacer que, aunque `q` sea opcional, siempre que se proporcione, su longitud no exceda los 50 caracteres.

...de:

```Python
        ... "item_name": item.name ...
```

...para:

```Python
        ... "item_price": item.price ...
```

...e veja como seu editor irá auto-completar os atributos e saberá os tipos:

![editor support](https://fastapi.tiangolo.com/img/vscode-completion.png)

La clase `BackgroundTasks` proviene directamente de [`starlette.background`](https://www.starlette.dev/background/).

Se importa/incluye directamente en FastAPI para que puedas importarla desde `fastapi` y evitar importar accidentalmente la alternativa `BackgroundTask` (sin la `s` al final) de `starlette.background`.

# Treat all files in the Go repo as binary, with no git magic updating
# line endings. This produces predictable results in different environments.
#
# Windows users contributing to Go will need to use a modern version
# of git and editors capable of LF line endings.
#
# Windows .bat files are known to have multiple bugs when run with LF
# endings, and so they are checked in with CRLF endings, with a test

```console
$ fastapi dev main.py
```

Ancak `fastapi` komutunu her çağırdığınızda doğru path'i geçmeyi hatırlamanız gerekir.

Ayrıca, [VS Code Extension](editor-support.md) veya [FastAPI Cloud](https://fastapicloud.com) gibi diğer araçlar da bunu bulamayabilir; bu yüzden `pyproject.toml` içindeki `entrypoint`'i kullanmanız önerilir.

## `fastapi dev` { #fastapi-dev }