**`kclient.Client`** is a higher level wrapper around a Kubernetes resource, and is built up of sub-parts `kclient.Reader`, `kclient.Writer`, and `kclient.Informer`.
Typically, the whole `kclient.Client` is used,though.

Functionality offered by `kclient` includes:
* Typed clients (via generics) and more ergonomic APIs
* Ability to make a _delayed_ client. This is used when making clients based on CRDs that may not exist.

		GetTlsCertificate().
		GetCertificateChain().
		GetInlineBytes()
	caDataSecret := secretTyped.
		GetValidationContext().
		GetTrustedCa().
		GetInlineBytes()

	// seems as though the most straightforward way to tell whether this is a root ca or not
	// is to check whether the inline bytes of the cert chain or the trusted ca field is zero length
	if len(certChainSecret) > 0 {

  // different than the options the caller provided. e.g. for a patch request the performed
  // Operation might be a CREATE, in which case the Options will a
  // `meta.k8s.io/v1.CreateOptions` even though the caller provided `meta.k8s.io/v1.PatchOptions`.
  // +optional
  optional k8s.io.apimachinery.pkg.runtime.RawExtension options = 12;
}

// AdmissionResponse describes an admission response.

	log := repairLog.WithLabels("pod", pod.Namespace+"/"+pod.Name)
	key := types.NamespacedName{Name: pod.Name, Namespace: pod.Namespace}
	// We will get an event every time the pod changes. The repair is not instantaneous, though -- it will only recover
	// once the pod restarts (in CrashLoopBackoff), which can take some time.
	// We don't want to constantly try to apply the iptables rules, which is unneeded and will fail.

	s.pods.AddEventHandler(controllers.FromEventHandler(func(o controllers.Event) {
		s.queue.Add(o)
	}))

	// Namespaces could be anything though, so we watch all of those
	//
	// NOTE that we are requeueing namespaces here explicitly to work around
	// test flakes with the fake kube client in `pkg/kube/client.go` -

The target destination address is set in the `:authority` header, and additional headers can be included as well.
Currently, only HTTP/2 is supported, though HTTP/1.1 and HTTP/3 are planned.

Currently, SNI is not set by Istio clients and ignored by Istio servers.
This makes identifying which certificate to use problematic for Ztunnel.

charts unmodified (but validated through a
[schema](pkg/apis/istio/v1alpha1/values_types.proto)). Values.yaml settings
are overridden the same way as the new API, though a customized CR overlaid over default values for the selected
profile. Here's an example of overriding some global level default values ([samples/values-global.yaml](samples/values-global.yaml)):

```yaml

  // a direct binding between Ingress controller and Ingress resources. Newly
  // created Ingress resources should prefer using the field. However, even
  // though the annotation is officially deprecated, for backwards compatibility
  // reasons, ingress controllers should still honor that annotation if present.
  // +optional
  optional string ingressClassName = 4;

  // different than the options the caller provided. e.g. for a patch request the performed
  // Operation might be a CREATE, in which case the Options will a
  // `meta.k8s.io/v1.CreateOptions` even though the caller provided `meta.k8s.io/v1.PatchOptions`.
  // +optional
  optional k8s.io.apimachinery.pkg.runtime.RawExtension options = 12;
}

// AdmissionResponse describes an admission response.

Istio reads from over 20 different resources types, and aggregates them together to build the proxy configuration. These resources can be sourced from Kubernetes (via watches), files, or over xDS; Kubernetes is by far the most common usage, though.

Primarily for historical reasons, ingestion is split into a few components.

#### ConfigStore