Istiod is structured as a modular monolith, housing a wide range of functionality from certificate signing, proxy configuration (XDS), traditional Kubernetes controllers, and more.

## Proxy Configuration

Istiod's primary role - and most code - is to dynamically configure proxies (Envoy sidecars and ingress, gRPC, ztunnel, and more). This roughly consists of 3 parts:
1. Config ingestion (inputs to the system)
1. Config translation

With this in mind, Ztunnel supports two xDS resources: `Address` and `Authorization`.

### Address Type

The primary configuration consumed by Ztunnel is the [`Address` resource](../../pkg/workloadapi/workload.proto).
As the name suggests, an `Address` represents a particular IP Address.
This can be a `Service` or a `Workload`.

                false

            // no children of class and script initializers are used
            is KtAnonymousInitializer ->
                false

            // no child expressions of primary constructors.
            is KtPrimaryConstructor ->
                false // error?
            // no children of secondary constructs are used.
            is KtSecondaryConstructor ->
                false

h3. Looking up the plugin with a configuration

{!../../../docs_src/sql_databases_peewee/sql_app/models.py!}
```

!!! tip
    Peewee creates several magic attributes.

    It will automatically add an `id` attribute as an integer to be the primary key.

    It will chose the name of the tables based on the class names.

    For the `Item`, it will create an attribute `owner_id` with the integer ID of the `User`. But we don't declare it anywhere.

## Sponsors

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// the DaemonSet and StatefulSet controllers for update and rollback, this object is beta. However,
// it may be subject to name and representation changes in future releases, and clients should not
// depend on its stability. It is primarily for internal use by controllers.
message ControllerRevision {
  // Standard object's metadata.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
  // +optional

    }

    return KtFe10DescConstructorSymbol(this, analysisContext)
}

internal val CallableMemberDescriptor.ktHasStableParameterNames: Boolean
    get() = when {
        this is ConstructorDescriptor && isPrimary && constructedClass.kind == ClassKind.ANNOTATION_CLASS -> true
        isExpect -> false
        else -> when (this) {
            is JavaCallableMemberDescriptor -> false
            else -> hasStableParameterNames()

// the DaemonSet and StatefulSet controllers for update and rollback, this object is beta. However,
// it may be subject to name and representation changes in future releases, and clients should not
// depend on its stability. It is primarily for internal use by controllers.
message ControllerRevision {
  // Standard object's metadata.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
  // +optional

Entonces, relacionado con la paradoja del huevo y la gallina, ¿cómo se llama a la primera función `async`?

Si estás trabajando con **FastAPI** no tienes que preocuparte por eso, porque esa "primera" función será tu *path operation function*, y FastAPI sabrá cómo hacer lo pertinente.