* an application-specified ordering of lock acquisitions. The application defines the allowed
   * ordering with an {@code Enum} whose values each correspond to a lock type. The order in which
   * the values are declared dictates the allowed order of lock acquisition. In other words, locks
   * corresponding to smaller values of {@link Enum#ordinal()} should only be acquired before locks
   * with larger ordinals. Example:
   *

    * If it is not, the client will see a useful, clear error.
* Check if there is an optional query parameter named `q` (as in `http://127.0.0.1:8000/items/foo?q=somequery`) for `GET` requests.
    * As the `q` parameter is declared with `= None`, it is optional.
    * Without the `None` it would be required (as is the body in the case with `PUT`).
* For `PUT` requests to `/items/{item_id}`, read the body as JSON:

     * converter.apply(), anyway. If clients use only converter.convert(), then their nullness
     * checkers are unlikely to ever look at the annotations on this declaration.
     *
     * Historical note: At one point, we'd declared this method as accepting and returning nullable
     * values. For details on that, see earlier revisions of this file.
     */
    return convert(a);
  }

  /**

  // to these actions only if the FailurePolicy is set to Fail, otherwise the failures are
  // ignored. This includes compilation errors, runtime errors and misconfigurations of the policy.
  //
  // validationActions is declared as a set of action values. Order does
  // not matter. validationActions may not contain duplicates of the same action.
  //
  // The supported actions values are:
  //

* Fix controller-manager race condition issue which cause endpoints flush during restart ([#23035](https://github.com/kubernetes/kubernetes/pull/23035), [@xinxiaogang](https://github.com/xinxiaogang))
* MESOS: forward globally declared cadvisor housekeeping flags ([#22974](https://github.com/kubernetes/kubernetes/pull/22974), [@jdef](https://github.com/jdef))

```JSON
{
    "name": "Foo",
    "price": 45.2
}
```

## Déclarez-le comme paramètre

Pour l'ajouter à votre *opération de chemin*, déclarez-le comme vous déclareriez des paramètres de chemin ou de requête :

{* ../../docs_src/body/tutorial001.py hl[18] *}

...et déclarez que son type est le modèle que vous avez créé : `Item`.

## Résultats

The <code>DATA</code> directives for a given symbol must be written with increasing offsets.
</p>

<p>
The <code>GLOBL</code> directive declares a symbol to be global.
The arguments are optional flags and the size of the data being declared as a global,
which will have initial value all zeros unless a <code>DATA</code> directive
has initialized it.

Encore une fois, cela convertira les types de données, les validera, permettra de générer la documentation, etc...

## Paramètres multiples body et query

Bien entendu, vous pouvez déclarer autant de paramètres que vous le souhaitez, en plus des paramètres body déjà déclarés.

    * This is useful while calling external services, performing costly computation, etc.
    * This also means that if a dependency was declared as a *path operation decorator* dependency, possibly at the router level (with `.include_router()`) and then it is declared again in a specific *path operation*, the dependency will be called only once.

Vous pouvez déclarer plusieurs paramètres de chemin et paramètres de requête dans la même fonction, **FastAPI** saura comment les gérer.

Et vous n'avez pas besoin de les déclarer dans un ordre spécifique.

Ils seront détectés par leurs noms :

{* ../../docs_src/query_params/tutorial004.py hl[8,10] *}

## Paramètres de requête requis