Adding Owner References for Existing Resources
Owner references are automatically injected only during creation of resources. Enabling owner reference injection will not update objects
created while owner reference injection is
disabled
This guide will demonstrate how to retroactively set owner references for existing resources.
A GET request to the owning resource will provide the necessary data to
construct an ownerReference or an annotation.
$ kubectl get memcacheds.cache.example.com -o yaml
Example Response (Abbreviated):
apiVersion: cache.example.com/v1alpha1
kind: Memcached
metadata:
name: example-memcached
namespace: default
uid: 2a94ff2b-84e0-40ce-8b5e-2b7e4d2bc0e2
kubectl edit can be used to update the resources by hand. See below
for example ownerReference and annotations.
For objects in the same namespace as the Owner (CR)
Dependent resources within the same namespace as the owning CR are
tracked with the ownerReference field.
ownerReference structure:
- apiVersion: {group}/{version}
- kind: {kind}
- name: {metadata.name}
- uid: {metadata.uid}
Example ownerReference:
metadata:
...(snip)
ownerReferences:
- apiVersion: cache.example.com/v1alpha1
kind: Memcached
name: example-memcached
uid: ad834522-d9a5-4841-beac-991ff3798c00
For objects which are NOT in the same namespace as the Owner (CR)
An annotation is used instead of an ownerReference if the dependent
resource is in a different namespace than the CR, or the dependent
resource is a cluster level resource.
annotation structure:
- operator-sdk/primary-resource: {metadata.namespace}/{metadata.name}
- operator-sdk/primary-resource-type: {kind}.{group}
NOTE: The {group} can be found by splitting the apiVersion
metadata of the CR, into group and version. As an example,
apiVersion: cache.example.com/v1alpha1 in the config/samples directory
gives us the group cache.example.com.
Example Annotation:
metadata:
...(snip)
annotations:
operator-sdk/primary-resource: default/example-memcached
operator-sdk/primary-resource-type: Memcached.cache.example.com
Migration using Ansible assets
If you have many resources to update, it may be easier to use the following Ansible assets, which should be considered an example rather than an officially supported workflow.
To use these assets, create a vars.yml as specified below and copy
playbook.yml and each_resource.yml into the same directory. Execute
the playbook with:
$ ansible-playbook -i localhost playbook.yml
vars.yml
This file should be created by the user to configure the playbook, and needs to contain:
- owning_resource
- apiVersion
- kind
- name
- namespace
- resources_to_own (list): For each resource, specify:
- name
- namespace (if applicable)
- apiVersion
- kind
owning_resource:
apiVersion: cache.example.com/v1alpha1
kind: Memcached
name: example-memcached
namespace: default
resources_to_own:
- name: example-memcached-memcached
namespace: default
apiVersion: apps/v1
kind: Deployment
- name: example-memcached
apiVersion: v1
kind: Namespace
playbook.yml
This file can be used as-is without user adjustments.
- hosts: localhost
tasks:
- name: Import user variables
include_vars: vars.yml
- name: Retrieve owning resource
community.kubernetes.k8s_info:
api_version: "{{ owning_resource.apiVersion }}"
kind: "{{ owning_resource.kind }}"
name: "{{ owning_resource.name }}"
namespace: "{{ owning_resource.namespace }}"
register: extra_owner_data
- name: Ensure resources are owned
include_tasks: each_resource.yml
loop: "{{ resources_to_own }}"
vars:
to_be_owned: '{{ q("community.kubernetes.k8s",
api_version=item.apiVersion,
kind=item.kind,
resource_name=item.name,
namespace=item.namespace
).0 }}'
owner_reference:
apiVersion: "{{ owning_resource.apiVersion }}"
kind: "{{ owning_resource.kind }}"
name: "{{ owning_resource.name }}"
uid: "{{ extra_owner_data.resources[0].metadata.uid }}"
each_resource.yml
This file can be used as-is without user adjustments.
- name: Patch resource with owner reference
when:
- to_be_owned.metadata.namespace is defined
- to_be_owned.metadata.namespace == owning_resource.namespace
- (to_be_owned.metadata.ownerReferences is not defined) or
(owner_reference not in to_be_owned.metadata.ownerReferences)
community.kubernetes.k8s:
state: present
resource_definition:
apiVersion: "{{ to_be_owned.apiVersion }}"
kind: "{{ to_be_owned.kind }}"
metadata:
name: "{{ to_be_owned.metadata.name }}"
namespace: "{{ to_be_owned.metadata.namespace }}"
ownerReferences: "{{ (to_be_owned.metadata.ownerReferences | default([])) + [owner_reference] }}"
- name: Patch resource with owner annotation
when: to_be_owned.namespace is not defined or to_be_owned.namespace != owning_resource.namespace
community.kubernetes.k8s:
state: present
resource_definition:
apiVersion: "{{ to_be_owned.apiVersion }}"
kind: "{{ to_be_owned.kind }}"
metadata:
name: "{{ to_be_owned.metadata.name }}"
namespace: "{{ to_be_owned.metadata.namespace | default(omit)}}"
annotations:
operator-sdk/primary-resource: "{{ owning_resource.namespace }}/{{ owning_resource.name }}"
operator-sdk/primary-resource-type: "{{ owning_resource.kind }}.{{ owning_resource.apiVersion.split('/')[0] }}"