Por ejemplo, cuando usas GraphQL normalmente realizas todas las acciones usando solo operaciones `POST`.

///

### Paso 4: define la **path operation function**

Esta es nuestra "**path operation function**":

* **path**: es `/`.
* **operation**: es `get`.
* **function**: es la función debajo del "decorador" (debajo de `@app.get("/")`).

{* ../../docs_src/first_steps/tutorial001.py hl[7] *}

    }

    /**
     * Returns a {@link CopyOptions} with the specified property names to include in the operation.
     *
     * @param propertyNames
     *            An array of property names. Must not be {@literal null} or an empty array.
     * @return A {@link CopyOptions} with the specified property names to include in the operation.
     * @see CopyOptions#include(CharSequence...)
     */

/// tip

Note that, much like [dependencies in *path operation decorators*](dependencies/dependencies-in-path-operation-decorators.md){.internal-link target=_blank}, no value will be passed to your *path operation function*.

///

The end result is that the item paths are now:

* `/items/`
* `/items/{item_id}`

...as we intended.

```mermaid
sequenceDiagram

participant client as Client
participant handler as Exception handler
participant dep as Dep with yield
participant operation as Path Operation
participant tasks as Background tasks

    Note over client,operation: Puede lanzar excepciones, incluyendo HTTPException
    client ->> dep: Iniciar request
    Note over dep: Ejecutar código hasta yield
    opt raise Exception

      // the operation would be a no-op, so exceptions are allowed but not required
    }
    expectUnchanged();
  }

  @MapFeature.Require(absent = SUPPORTS_PUT)
  public void testReplaceEntry_unsupportedAbsentKey() {
    try {
      getMap().replace(k3(), v3(), v4());
    } catch (UnsupportedOperationException tolerated) {

      // the operation would be a no-op, so exceptions are allowed but not required
    }
    expectUnchanged();
  }

  @MapFeature.Require(absent = SUPPORTS_PUT)
  public void testReplaceEntry_unsupportedAbsentKey() {
    try {
      getMap().replace(k3(), v3(), v4());
    } catch (UnsupportedOperationException tolerated) {

 */
package org.codelibs.fess.exception;

/**
 * An exception thrown when an LDAP operation fails.
 */
public class LdapOperationException extends FessSystemException {

    private static final long serialVersionUID = 1L;

    /**
     * Constructs a new LDAP operation exception with the specified detail message and cause.
     *
     * @param message The detail message.

## Usando `BackgroundTasks`

Primero, importa `BackgroundTasks` y define un parámetro en tu *path operation function* con una declaración de tipo de `BackgroundTasks`:

{* ../../docs_src/background_tasks/tutorial001.py hl[1,13] *}

**FastAPI** creará el objeto de tipo `BackgroundTasks` por ti y lo pasará como ese parámetro.

Pero también puedes declarar el `Response` que quieres usar (por ejemplo, cualquier subclase de `Response`), en el *path operation decorator* usando el parámetro `response_class`.

Los contenidos que devuelvas desde tu *path operation function* se colocarán dentro de esa `Response`.

...le "path" serait :

```
/items/foo
```

/// info

Un chemin, ou "path" est aussi souvent appelé route ou "endpoint".

///

#### Opération

"Opération" fait référence à une des "méthodes" HTTP.

Une de :

* `POST`
* `GET`
* `PUT`
* `DELETE`

...ou une des plus exotiques :

* `OPTIONS`
* `HEAD`
* `PATCH`
* `TRACE`