*    purpose of the certificate like "Entrust Root Certification Authority - G2" or
 *    "www.squareup.com".
 *
 *  * **A set of hostnames.** These are in the certificate's subject alternative name (SAN)
 *    extension. A subject alternative name is either a literal hostname (`squareup.com`), a literal
 *    IP address (`74.122.190.80`), or a hostname pattern (`*.api.squareup.com`).
 *

// Client interface defines the clients need to implement to talk to CA for CSR.
// The Agent will create a key pair and a CSR, and use an implementation of this
// interface to get back a signed certificate. There is no guarantee that the SAN
// in the request will be returned - server may replace it.
type Client interface {
	CSRSign(csrPEM []byte, certValidTTLInSec int64) ([]string, error)
	Close()

			serverCert: serverCert, serverKey: serverKey,
			errRegex: errSignedByUnknownCA,
		},
		{
			// this will fail when GODEBUG is set to x509ignoreCN=0 with
			// expected err, but the SAN counter gets increased
			test:       "server cert does not have SAN extension",
			clientCA:   caCert,
			serverCert: serverCertNoSAN, serverKey: serverKey,
			errRegex:               "x509: certificate relies on legacy Common Name field",

												},
											},
										},
									},
								},
							},
						},
					},
				},
			},
		},
		{
			name: "MTLSStrict using SDS and SAN aliases",
			node: &model.Proxy{
				Metadata: &model.NodeMetadata{},
			},
			validateClient:     true,
			trustDomainAliases: []string{"alias-1.domain", "some-other-alias-1.domain", "alias-2.domain"},

			options.NetworkingDNSDomain,
			options.NetworkingServiceSubnet,
		)
	}
	return flags
}

func getSANDescription(certSpec *certsphase.KubeadmCert) string {
	// Defaulted config we will use to get SAN certs
	defaultConfig := &kubeadmapiv1.InitConfiguration{
		LocalAPIEndpoint: kubeadmapiv1.APIEndpoint{
			// GetAPIServerAltNames errors without an AdvertiseAddress; this is as good as any.
			AdvertiseAddress: "127.0.0.1",

}

func (a *Agent) generateNodeMetadata() (*model.Node, error) {
	var pilotSAN []string
	if a.proxyConfig.ControlPlaneAuthPolicy == mesh.AuthenticationPolicy_MUTUAL_TLS {
		// Obtain Pilot SAN, using DNS.
		pilotSAN = []string{config.GetPilotSan(a.proxyConfig.DiscoveryAddress)}
	}

	credentialSocketExists, err := checkSocket(context.TODO(), security.CredentialNameSocketPath)
	if err != nil {

	return altNames, nil
}

// GetEtcdAltNames builds an AltNames object for generating the etcd server certificate.
// `advertise address` and localhost are included in the SAN since this is the interfaces the etcd static pod listens on.
// The user can override the listen address with `Etcd.ExtraArgs` and add SANs with `Etcd.ServerCertSANs`.

  repeated NetworkAddress addresses = 4;
  // Ports for the service.
  // The target_port may be overridden on a per-workload basis.
  repeated Port ports = 5;
  // Optional; if set, the SAN to verify for TLS connections.
  // Typically, this is not set and per-workload identity is used to verify
  // TODO: support this field
  repeated string subject_alt_names = 6;

* 100% <abbr title="Python type annotations, với điều này trình soạn thảo của bạn và các công cụ bên ngoài có thể hỗ trợ bạn tốt hơn">type annotated</abbr> code base.
* Được sử dụng cho các ứng dụng sản phẩm.

## Tính năng của Starlette

`FastAPI` is thực sự là một sub-class của `Starlette`. Do đó, nếu bạn đã biết hoặc đã sử dụng Starlette, đa số các chức năng sẽ làm việc giống như vậy.

	IsSelfSigned bool

	// Whether this certificate is for a client.
	IsClient bool

	// Whether this certificate is for a server.
	IsServer bool

	// Whether this certificate is for dual-use clients (SAN+CN).
	IsDualUse bool

	// If true, the private key is encoded with PKCS#8.
	PKCS8Key bool

	// The type of Elliptical Signature algorithm to use
	// when generating private keys. Currently only ECDSA is supported.