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

  // Group is the API Group of the Resource.  "*" means all.
  // +optional
  optional string group = 3;

  // Version is the API Version of the Resource.  "*" means all.
  // +optional
  optional string version = 4;

  // Resource is one of the existing resource types.  "*" means all.
  // +optional
  optional string resource = 5;

  // Subresource is one of the existing resource types.  "" means none.
  // +optional

  // APIVersions is the API versions the resources belong to. '*' is all versions.
  // If '*' is present, the length of the slice must be one.
  // Required.
  // +listType=atomic
  repeated string apiVersions = 2;

  // Resources is a list of resources this rule applies to.
  //
  // For example:
  // 'pods' means pods.
  // 'pods/log' means the log subresource of pods.
  // '*' means all resources, but not subresources.

                            public abstract Property<String> getSourceCompatibility();
                        }
                    """
                )
                withFile(
                    "resources/upgraded-properties.json",
                    """
                        [{
                            "containingType": "com.example.Task",
                            "methodName": "getSourceCompatibility",

  // +optional
  optional string apiGroup = 1;

  // Kind is the type of resource being referenced. This is the same
  // value as in the parameter object's metadata.
  optional string kind = 2;

  // Name is the name of resource being referenced.
  optional string name = 3;

  // Namespace that contains the referenced resource. Must be empty

  // Group is the API Group of the Resource.  "*" means all.
  // +optional
  optional string group = 3;

  // Version is the API Version of the Resource.  "*" means all.
  // +optional
  optional string version = 4;

  // Resource is one of the existing resource types.  "*" means all.
  // +optional
  optional string resource = 5;

  // Subresource is one of the existing resource types.  "" means none.
  // +optional

            it.value.isNotEmpty()
        } ?: emptyMap()

    /**
     * Returns any temporary directories used to extract resources from jars.
     *
     * These directories will be created as siblings of the randomly assigned test root directories, with the fixed name {@code tmp-extracted-resources}.
     */
    private

 * dependencies - resources - configuration - extension points of plugins
 *
 * For a particular application plugin there will be a declarative descriptor for that plugin type.
 *
 * - nexus - the plugin class - UI to contribute - what JS to hook into the UI - what resources to
 * load into the UI - having packed or unpacked plugins, and positioning resources if necessary -

way as galley settings. Supported K8s settings currently include:

- [resources](https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/#resource-requests-and-limits-of-pod-and-container)
- [readiness probes](https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-probes/)

  // Kind is the API kind the resources belong to.
  // Required.
  optional string kind = 2;
}

// ParamRef references a parameter resource
// +structType=atomic
message ParamRef {
  // Name of the resource being referenced.
  optional string name = 1;

  // Namespace of the referenced resource.
  // Should be empty for the cluster-scoped resources
  // +optional
  optional string namespace = 2;
}