feat(chart): add crds.install flag to gate DNSEndpoint CRD installation

charts/external-dns/CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Add value `.service.enabled` to enable the creation of the Kubernetes service.
 - Add value `replicaCount` to set the number of `external-dns` replicas (bounded to `0` or `1`, since external-dns does not support leader election). [#6503](https://github.com/kubernetes-sigs/external-dns/pull/6503) _@yugstar_
+- Add value `.crds.install` to control whether the `DNSEndpoint` `CustomResourceDefinition` is installed. Defaults to `true`; set to `false` on all but one release when running multiple `external-dns` releases (e.g. one per provider) in the same cluster to avoid the CRD being installed more than once. Note: because the CRD is now rendered from `templates/`, Helm may attempt to update it on upgrade and will delete it on uninstall unless it is marked with `helm.sh/resource-policy: keep`.
 
 ### Changed
 

charts/external-dns/README.md

@@ -98,6 +98,7 @@ If `namespaced` is set to `true`, please ensure that `sources` only contains sup
 | annotationPrefix | string | `nil` | Annotation prefix for external-dns annotations (useful for split horizon DNS with multiple instances). |
 | automountServiceAccountToken | bool | `true` | Set this to `false` to [opt out of API credential automounting](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/#opt-out-of-api-credential-automounting) for the `Pod`. |
 | commonLabels | object | `{}` | Labels to add to all chart resources. |
+| crds.install | bool | `true` | If `true`, install the `DNSEndpoint` `CustomResourceDefinition`. Set this to `false` on all but one release when running multiple `external-dns` releases (e.g. one per provider) in the same cluster, to avoid the CRD being installed more than once. |
 | deploymentAnnotations | object | `{}` | Annotations to add to the `Deployment`. |
 | deploymentStrategy | object | `{"type":"Recreate"}` | [Deployment Strategy](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#strategy). |
 | dnsConfig | object | `nil` | [DNS config](https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/#pod-dns-config) for the pod, if not set the default will be used. |

charts/external-dns/crds/dnsendpoints.externaldns.k8s.io.yaml → charts/external-dns/templates/dnsendpoint-crd.yaml

@@ -1,9 +1,12 @@
+{{- if .Values.crds.install -}}
 apiVersion: apiextensions.k8s.io/v1
 kind: CustomResourceDefinition
 metadata:
   annotations:
     api-approved.kubernetes.io: https://github.com/kubernetes-sigs/external-dns/pull/2007
   name: dnsendpoints.externaldns.k8s.io
+  labels:
+    {{- include "external-dns.labels" . | nindent 4 }}
 spec:
   group: externaldns.k8s.io
   names:
@@ -94,3 +97,4 @@ spec:
       storage: true
       subresources:
         status: {}
+{{- end }}

charts/external-dns/tests/crds_test.yaml

@@ -0,0 +1,25 @@
+suite: CRD configuration
+set:
+  policy: upsert-only
+templates:
+  - dnsendpoint-crd.yaml
+release:
+  namespace: default
+tests:
+  - it: should install the DNSEndpoint CRD by default
+    asserts:
+      - hasDocuments:
+          count: 1
+      - isKind:
+          of: CustomResourceDefinition
+      - equal:
+          path: metadata.name
+          value: dnsendpoints.externaldns.k8s.io
+
+  - it: should not install the CRD when crds.install is false
+    set:
+      crds:
+        install: false
+    asserts:
+      - hasDocuments:
+          count: 0

charts/external-dns/values.schema.json

@@ -31,6 +31,15 @@
       "description": "Labels to add to all chart resources.",
       "type": "object"
     },
+    "crds": {
+      "type": "object",
+      "properties": {
+        "install": {
+          "description": "If `true`, install the `DNSEndpoint` `CustomResourceDefinition`. Set this to `false` on all but one release when running multiple `external-dns` releases (e.g. one per provider) in the same cluster, to avoid the CRD being installed more than once.",
+          "type": "boolean"
+        }
+      }
+    },
     "deploymentAnnotations": {
       "description": "Annotations to add to the `Deployment`.",
       "type": "object"

charts/external-dns/values.yaml

@@ -64,6 +64,10 @@ rbac:  # @schema additionalProperties: true
   # -- Additional rules to add to the `ClusterRole`.
   additionalPermissions: []
 
+crds:
+  # -- If `true`, install the `DNSEndpoint` `CustomResourceDefinition`. Set this to `false` on all but one release when running multiple `external-dns` releases (e.g. one per provider) in the same cluster, to avoid the CRD being installed more than once.
+  install: true
+
 # -- Number of replicas of the `external-dns` `Deployment`. external-dns does not
 # support leader election, so this must be `0` or `1` to avoid duplicate or
 # conflicting DNS record updates. Set to `0` to scale the `Deployment` down.