Esto es muy útil cuando necesitas:

* Tener lógica compartida (la misma lógica de código una y otra vez).
* Compartir conexiones a bases de datos.
* Imponer seguridad, autenticación, requisitos de roles, etc.
* Y muchas otras cosas...

Todo esto, mientras minimizas la repetición de código.

## Primeros Pasos { #first-steps }

Veamos un ejemplo muy simple. Será tan simple que no es muy útil, por ahora.

C’est très utile lorsque vous avez besoin de :

* Avoir de la logique partagée (la même logique de code encore et encore).
* Partager des connexions à la base de données.
* Imposer la sécurité, l’authentification, des exigences de rôles, etc.
* Et bien d’autres choses ...

Tout cela, en minimisant la répétition de code.

## Premiers pas { #first-steps }

        while (parser.getEventType() == XmlPullParser.START_TAG) {
            // update properties inside the bean, guided by the cached property map
            final BeanProperty<Object> property = propertyMap.get(Roles.camelizeName(parser.getName()));
            if (property != null) {
                property.set(bean, parse(parser, property.getType()));
                parser.nextTag();
            } else {

    it keeps your `HeldCertificate` and its chain. On the client it keeps the root certificates
    that are trusted to sign a server's certificate chain. `HandshakeCertificates` also works with
    mutual TLS where these roles are reversed.

    These classes make it possible to enable HTTPS in MockWebServer in [just a few lines of
    code][https_server_sample].

	}
	sort.Strings(arns)
	msgs := make([]string, 0, len(arns))
	for _, arn := range arns {
		msgs = append(msgs, color.Bold(arn))
	}

	logger.Info(fmt.Sprintf("%s %s", color.Blue("IAM Roles:"), strings.Join(msgs, " ")))
}

// HasWatcher - returns if the IAM system has a watcher to be notified of
// changes.
func (sys *IAMSys) HasWatcher() bool {
	return sys.store.HasWatcher()
}

			 <!--
			 "node.name":"search_engine",
			 "discovery.seed_hosts":"search_engine",
			 "cluster.initial_cluster_manager_nodes":"search_engine",
			 "node.roles":"cluster_manager,data,ingest,ml",
			 -->
			 "indices.breaker.total.limit":"100%",
			 "action.auto_create_index":"-*"}
		</property>
		<!-- Dictionaries -->
		<postConstruct name="addConfigFile">

* Kubernetes now supports up to 5,000 nodes via etcd v3, which is enabled by default.
* [Role-based access control (RBAC)](https://kubernetes.io//docs/admin/authorization/rbac) has graduated to beta, and defines secure default roles for control plane, node, and controller components.
* The [`kubeadm` cluster bootstrap tool](https://kubernetes.io/docs/getting-started-guides/kubeadm/) has graduated to beta. Some highlights:

* corrects a race condition in bootstrapping aggregated cluster roles in new HA clusters ([#63761](https://github.com/kubernetes/kubernetes/pull/63761), [@liggitt](https://github.com/liggitt))

  - The built-in `system:csi-external-provisioner` and `system:csi-external-attacher` cluster roles are deprecated and will not be auto-created in a future release. CSI deployments should provide their own RBAC role definitions with required permissions. ([#69868](https://github.com/kubernetes/kubernetes/pull/69868), [@pohly]( https://github.com/pohly))...

but Websocket requests only required `get` permission. This change is gated by the `AuthorizePodWebsocketUpgradeCreatePermission` feature-gate, which is enabled by default.
  
  Before upgrading to 1.35, ensure any custom ClusterRoles and Roles intended to grant `pods/exec`, `pods/attach`, or `pods/portforward` permission include the `create` verb. ([#134577](https://github.com/kubernetes/kubernetes/pull/134577), [@seans3](https://github.com/seans3)) [SIG API Machinery, Auth, Node and Testing]...