///

## Check the automatic API docs

Now, run your app:

<div class="termy">

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

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

And open the docs at <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

Pydantic, which is what powers all the data validation and serialization in FastAPI, has a special behavior when you use `Optional` or `Union[Something, None]` without a default value, you can read more about it in the Pydantic docs about <a href="https://docs.pydantic.dev/2.3/usage/models/#required-optional-fields" class="external-link" target="_blank">Required fields</a>.

///

/// tip

`@lru_cache` is part of `functools` which is part of Python's standard library, you can read more about it in the <a href="https://docs.python.org/3/library/functools.html#functools.lru_cache" class="external-link" target="_blank">Python docs for `@lru_cache`</a>.

## Recap

You can use Pydantic Settings to handle the settings or configurations for your application, with all the power of Pydantic models.

* Sie können Metadaten aus der hochgeladenen Datei auslesen.
* Es hat eine <abbr title="dateiartig"><a href="https://docs.python.org/3/glossary.html#term-file-like-object" class="external-link" target="_blank">file-like</a></abbr> `async`hrone Schnittstelle.

* Você pode obter metadados do arquivo enviado.
* Ela possui uma interface <a href="https://docs.python.org/3/glossary.html#term-file-like-object" class="external-link" target="_blank">semelhante a arquivos</a> `async`.

///

### Check the docs

Now you can start your app and go to <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

You will see your docs including a "Callbacks" section for your *path operation* that shows how the *external API* should look like:

updateStrategy: RollingUpdate ## Pod priority settings ## ref: https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/ ## priorityClassName: "" ## Pod runtime class name ## ref https://kubernetes.io/docs/concepts/containers/runtime-class/ ## runtimeClassName: "" ## Set default rootUser, rootPassword ## AccessKey and secretKey is generated when not set ## Distributed MinIO ref: https://docs.minio.io/docs/distributed-minio-quickstart-guide ## rootUser: "" rootPassword: "" ## Use existing...

updateStrategy: RollingUpdate ## Pod priority settings ## ref: https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/ ## priorityClassName: "" ## Pod runtime class name ## ref https://kubernetes.io/docs/concepts/containers/runtime-class/ ## runtimeClassName: "" ## Set default rootUser, rootPassword ## AccessKey and secretKey is generated when not set ## Distributed MinIO ref: https://docs.minio.io/docs/distributed-minio-quickstart-guide ## rootUser: "" rootPassword: "" ## Use existing...

updateStrategy: RollingUpdate ## Pod priority settings ## ref: https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/ ## priorityClassName: "" ## Pod runtime class name ## ref https://kubernetes.io/docs/concepts/containers/runtime-class/ ## runtimeClassName: "" ## Set default rootUser, rootPassword ## AccessKey and secretKey is generated when not set ## Distributed MinIO ref: https://docs.minio.io/docs/distributed-minio-quickstart-guide ## rootUser: "" rootPassword: "" ## Use existing...

      when (val protocol = sslSocket.applicationProtocol) {
        null, "" -> null
        else -> protocol
      }
    } catch (e: UnsupportedOperationException) {
      // https://docs.oracle.com/javase/9/docs/api/javax/net/ssl/SSLSocket.html#getApplicationProtocol--
      null
    }
  }

  @SuppressLint("NewApi")
  override fun configureTlsExtensions(
    sslSocket: SSLSocket,
    hostname: String?,