groups-and-versions.md

The Kubernetes Applications SIG defines the Application CRD for defining Kubernetes applications consisting of multiple resources, known as components.

The specification defines a spec field componentKinds which is an array of the components of an application.

spec:
  componentKinds:
    - group: core
      kind: Service
    - group: apps
      kind: Deployment

Only group and kind are currently defined for an application component.

Invalid group names and backward compatibility

Initial implementations of Application Navigator allowed invalid values to be specified for group which could cause errors when multiple CRDs have the same kind but different groups.

• Backward Compatible Kinds

  When an invalid group is specified for any of the following kinds the group and version in the table will be used:

  Kind	Group	Version
  Application	app.k8s.io	v1beta1
  ClusterRole	rbac.authorization.k8s.io	v1
  ClusterRoleBinding	rbac.authorization.k8s.io	v1
  ConfigMap		v1
  CustomResourceDefinition	apiextensions.k8s.io	v1beta1
  Deployment	apps	v1
  Endpoint		v1
  Ingress	extensions	v1beta1
  Job	batch	v1
  Node		v1
  PersistentVolumeClaim		v1
  Role	rbac.authorization.k8s.io	v1
  RoleBinding	rbac.authorization.k8s.io	v1
  Route	route.openshift.io	v1
  Secret		v1
  Service		v1
  ServiceAccount		v1
  StatefulSet	apps	v1
  StorageClass	storage.k8s.io	v1
  Volume		v1

Special group name "core"

The group: value core is used to specify kinds that are built in to Kubernetes. These core builtin kinds have a blank/empty group internally.

    - group: core
      kind: Service

Versions

The version for each group/kind will be the preferred version for the group, as determined by Kubernetes discovery, since the spec does not provide a way to specify version.