```Python
q: Union[str, None] = Query(default=None, max_length=50)
```

Cela va valider les données, montrer une erreur claire si ces dernières ne sont pas valides, et documenter le paramètre dans le schéma `OpenAPI` de cette *path operation*.

## Rajouter plus de validation

Vous pouvez aussi rajouter un second paramètre `min_length` :

{* ../../docs_src/query_params_str_validations/tutorial003.py hl[9] *}

# Headers de Respuesta

## Usar un parámetro `Response`

Puedes declarar un parámetro de tipo `Response` en tu *función de operación de path* (de manera similar como se hace con las cookies).

Y entonces, podrás configurar las cookies en ese objeto de response *temporal*.

```Python hl_lines="1  7-8"
{!../../docs_src/response_headers/tutorial002.py!}
```

        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/user/": {
                "post": {
                    "summary": "Create User",
                    "operationId": "create_user_user__post",
                    "requestBody": {
                        "content": {
                            "application/json": {

                                    }
                                }
                            },
                        },
                    },
                    "summary": "Read Item",
                    "operationId": "read_item_items__item_id__get",
                    "parameters": [
                        {
                            "required": True,
                            "schema": {"title": "Item Id", "type": "string"},

indent 12 }} {{- with .Values.nodeSelector }} nodeSelector: {{ toYaml . | indent 8 }} {{- end }} {{- include "minio.imagePullSecrets" . | indent 6 }} {{- with .Values.affinity }} affinity: {{ toYaml . | indent 8 }} {{- end }} {{- with .Values.tolerations }} tolerations: {{ toYaml . | indent 8 }} {{- end }} volumes: - name: export {{- if .Values.persistence.enabled }} persistentVolumeClai: claimName: {{ .Values.persistence.existingClaim | default (include "minio.fullname" .) }} {{- else }} emptyDir: {}...

indent 12 }} {{- with .Values.nodeSelector }} nodeSelector: {{ toYaml . | indent 8 }} {{- end }} {{- include "minio.imagePullSecrets" . | indent 6 }} {{- with .Values.affinity }} affinity: {{ toYaml . | indent 8 }} {{- end }} {{- with .Values.tolerations }} tolerations: {{ toYaml . | indent 8 }} {{- end }} volumes: - name: export {{- if .Values.persistence.enabled }} persistentVolumeClai: claimName: {{ .Values.persistence.existingClaim | default (include "minio.fullname" .) }} {{- else }} emptyDir: {}...

indent 12 }} {{- with .Values.nodeSelector }} nodeSelector: {{ toYaml . | indent 8 }} {{- end }} {{- include "minio.imagePullSecrets" . | indent 6 }} {{- with .Values.affinity }} affinity: {{ toYaml . | indent 8 }} {{- end }} {{- with .Values.tolerations }} tolerations: {{ toYaml . | indent 8 }} {{- end }} volumes: - name: export {{- if .Values.persistence.enabled }} persistentVolumeClai: claimName: {{ .Values.persistence.existingClaim | default (include "minio.fullname" .) }} {{- else }} emptyDir: {}...

indent 12 }} {{- with .Values.nodeSelector }} nodeSelector: {{ toYaml . | indent 8 }} {{- end }} {{- include "minio.imagePullSecrets" . | indent 6 }} {{- with .Values.affinity }} affinity: {{ toYaml . | indent 8 }} {{- end }} {{- with .Values.tolerations }} tolerations: {{ toYaml . | indent 8 }} {{- end }} volumes: - name: export {{- if .Values.persistence.enabled }} persistentVolumeClai: claimName: {{ .Values.persistence.existingClaim | default (include "minio.fullname" .) }} {{- else }} emptyDir: {}...

The recommended way to file an issue is by running `go bug`.
Otherwise, when filing an issue, make sure to answer these five questions:

1. What version of Go are you using (`go version`)?
2. What operating system and processor architecture are you using?
3. What did you do?
4. What did you expect to see?
5. What did you see instead?

For change proposals, see [Proposing Changes To Go](https://go.dev/s/proposal-process).

# GraphQL

Como **FastAPI** está basado en el estándar **ASGI**, es muy fácil integrar cualquier library **GraphQL** que sea compatible con ASGI.

Puedes combinar *operaciones de path* regulares de la library de FastAPI con GraphQL en la misma aplicación.

/// tip | Consejo

**GraphQL** resuelve algunos casos de uso específicos.

Tiene **ventajas** y **desventajas** cuando lo comparas con **APIs web** comunes.