```Python hl_lines="13  15  22  25"
{!../../docs_src/background_tasks/tutorial002.py!}
```

Neste exemplo, as mensagens serão gravadas no arquivo `log.txt` _após_ o envio da resposta.

Se houver uma consulta na solicitação, ela será gravada no log em uma tarefa em segundo plano.

* Então ele retorna a **resposta**.

/// note | "Detalhes técnicos"

Se você tiver dependências com `yield`, o código de saída será executado *depois* do middleware.

Se houver alguma tarefa em segundo plano (documentada posteriormente), ela será executada *depois* de todo o middleware.

///

## Criar um middleware

Para criar um middleware, use o decorador `@app.middleware("http")` logo acima de uma função.

### Telemetry Integration Tests

- **Location**: `tests/integration/telemetry`
- **Purpose**: Tests related to telemetry features, including metrics, logging, and tracing.
- **Focus**:
  1. Collection and processing of telemetry data.
  1. Interaction between telemetry components and Istio control plane.

{* ../../docs_src/background_tasks/tutorial002.py hl[13,15,22,25] *}

Dans cet exemple, les messages seront écrits dans le fichier `log.txt` après que la réponse soit envoyée.

S'il y avait une `query` (paramètre nommé `q`) dans la requête, alors elle sera écrite dans `log.txt` via une tâche d'arrière-plan.

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net"
	"net/url"
	"os"
	"strings"

	discovery "github.com/envoyproxy/go-control-plane/envoy/service/discovery/v3"
	xdsstatus "github.com/envoyproxy/go-control-plane/envoy/service/status/v3"
	"google.golang.org/grpc"
	v1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	"istio.io/api/label"

import org.apache.maven.project.MavenProject;

/**
 * Lifecycle mapping delegate component interface. Calculates project build execution plan given {@link Lifecycle} and
 * lifecycle phase. Standard lifecycles use plugin execution {@code <phase>} or mojo default lifecycle phase to
 * calculate the execution plan, but custom lifecycles can use alternative mapping strategies.
 * <p>

stable version in place and gradually migrate apps to the new version.

- More flexibility: the new installer allows multiple 'environments', allowing applications to select
a set of control plane settings and components. While the entire mesh respects the same APIs and config,
apps may target different 'environments' which contain different instances and variants of Istio.

restores the installation and use of preinstalled `.a` files.

There is no plan to remove any of these settings.

### Go 1.19

Go 1.19 made it an error for path lookups to resolve to binaries in the current directory,
controlled by the [`execerrdot` setting](/pkg/os/exec#hdr-Executables_in_the_current_directory).
There is no plan to remove this setting.

Go 1.19 started sending EDNS0 additional headers on DNS requests.

	if err != nil {
		return isZtunnel
	}
	if v, ok := pod.Labels["app"]; ok {
		return v == "ztunnel"
	}
	return isZtunnel
}

// InAmbient returns true if a resource is in ambient data plane mode.
func InAmbient(obj metav1.Object) bool {
	if obj == nil {
		return false
	}
	switch t := obj.(type) {
	case *corev1.Pod:

// limitations under the License.

package sdscompare

import (
	"crypto/x509"
	"encoding/pem"
	"fmt"
	"time"

	envoy_admin "github.com/envoyproxy/go-control-plane/envoy/admin/v3"
	auth "github.com/envoyproxy/go-control-plane/envoy/extensions/transport_sockets/tls/v3"

	"istio.io/istio/istioctl/pkg/util/configdump"
	"istio.io/istio/pkg/log"
)