[[service_injection]]
= Understanding Services and Service Injection

Gradle provides a number of useful services that can be used by custom Gradle types.
For example, the link:{javadocPath}/org/gradle/workers/WorkerExecutor.html[WorkerExecutor] service can be used by a task to run work in parallel, as seen in the <<worker_api.adoc#worker_api,worker API>> section.
The services are made available through _service injection_.

[[services_for_injection]]

  namespaceSelector:
    matchExpressions:
    - key: istio.io/rev
      operator: In
      values:
      - "{{ $tagName }}"
    - key: istio-injection
      operator: DoesNotExist
  objectSelector:
    matchExpressions:
    - key: sidecar.istio.io/inject
      operator: NotIn
      values:
      - "false"

  istioctl x check-inject deployment/details-v1

  # Check the injection status of a pod under a deployment in namespace test
  istioctl x check-inject deployment/details-v1 -n test

  # Check the injection status of label pairs in a specific namespace before actual injection 
  istioctl x check-inject -n test -l app=helloworld,version=v1
`,
		Args: func(cmd *cobra.Command, args []string) error {

		name     string
		pod      *corev1.Pod
		expected bool
	}{
		{
			name: "Injection disabled by annotation",
			pod: &corev1.Pod{
				ObjectMeta: metav1.ObjectMeta{
					Annotations: map[string]string{
						annotation.SidecarInject.Name: "false",
					},
				},
			},
			expected: true,
		},
		{
			name: "Injection enabled by annotation",
			pod: &corev1.Pod{
				ObjectMeta: metav1.ObjectMeta{

	injectPath := args.InjectionOptions.InjectionDirectory
	if injectPath == "" || !injectionEnabled.Get() {
		log.Infof("Skipping sidecar injector, injection path is missing or disabled.")
		return nil, nil
	}

	// If the injection config exists either locally or remotely, we will set up injection.
	var watcher inject.Watcher
	if _, err := os.Stat(filepath.Join(injectPath, "config")); !os.IsNotExist(err) {

  namespaceSelector:
    matchExpressions:
    - key: istio.io/rev
      operator: In
      values:
      - "default"
    - key: istio-injection
      operator: DoesNotExist
  objectSelector:
    matchExpressions:
    - key: sidecar.istio.io/inject
      operator: NotIn
      values:
      - "false"

	// Pilot injects this outbound filter if the service port name is `redis`.
	EnableRedisFilter = env.Register(
		"PILOT_ENABLE_REDIS_FILTER",
		false,
		"EnableRedisFilter enables injection of `envoy.filters.network.redis_proxy` in the filter chain.",
	).Get()

	// EnableMongoFilter enables injection of `envoy.filters.network.mongo_proxy` in the filter chain.

		return true
	}

	// If Pod has labels, return the injection label value
	if piv, ok := getPodSidecarInjectionStatus(labels); ok {
		return piv
	}

	// If Pod has annotation, return the injection annotation value
	if piv, ok := getPodSidecarInjectionStatus(annos); ok {
		return piv
	}

	// In case the annotation is not present but there is a auto-injection label on the namespace,
	// return the auto-injection label status

  matchPolicy: Equivalent
  name: rev.namespace.sidecar-injector.istio.io
  namespaceSelector:
    matchExpressions:
    - key: istio.io/rev
      operator: In
      values:
      - default
    - key: istio-injection
      operator: DoesNotExist
  objectSelector:
    matchExpressions:
    - key: sidecar.istio.io/inject
      operator: NotIn
      values:
      - "false"
  reinvocationPolicy: Never
  rules:

		&gateway.IngressGatewayPortAnalyzer{},
		&gateway.CertificateAnalyzer{},
		&gateway.SecretAnalyzer{},
		&gateway.ConflictingGatewayAnalyzer{},
		&injection.Analyzer{},
		&injection.ImageAnalyzer{},
		&injection.ImageAutoAnalyzer{},
		&k8sgateway.SelectorAnalyzer{},
		&multicluster.MeshNetworksAnalyzer{},
		&service.PortNameAnalyzer{},
		&sidecar.SelectorAnalyzer{},