fix: add name validation for custom resource templates

This further propagates the label constraints of Linode resources to their
associated CustomResourceDefinition templates via the Kubernetes Validation
Rules feature.

config/crd/kustomization.yaml

@@ -43,12 +43,24 @@ patches:
     kind: CustomResourceDefinition
     name: linodeclusters.infrastructure.cluster.x-k8s.io
   path: patches/validation_in_linodeclusters.yaml
+- target:
+    group: apiextensions.k8s.io
+    version: v1
+    kind: CustomResourceDefinition
+    name: linodeclustertemplates.infrastructure.cluster.x-k8s.io
+  path: patches/validation_in_linodeclustertemplates.yaml
 - target:
     group: apiextensions.k8s.io
     version: v1
     kind: CustomResourceDefinition
     name: linodemachines.infrastructure.cluster.x-k8s.io
   path: patches/validation_in_linodemachines.yaml
+- target:
+    group: apiextensions.k8s.io
+    version: v1
+    kind: CustomResourceDefinition
+    name: linodemachinetemplates.infrastructure.cluster.x-k8s.io
+  path: patches/validation_in_linodemachinetemplates.yaml
 - target:
     group: apiextensions.k8s.io
     version: v1

config/crd/patches/validation_in_linodeclustertemplates.yaml

@@ -0,0 +1,12 @@
+# The following patch adds additional constraints after the built-in name validation for the CRD
+- op: add
+  path: /spec/versions/0/schema/openAPIV3Schema/properties/metadata/properties
+  value:
+    name:
+      type: string
+      x-kubernetes-validations:
+      - rule: 3 <= size(self) && size(self) <= 26
+        message: >-
+          custom validation:
+          template: must be between 3..26 characters,
+          linode nodebalancer: labels must be between 3..32 characters

config/crd/patches/validation_in_linodemachinetemplates.yaml

@@ -0,0 +1,27 @@
+# The following patch adds additional constraints after the built-in name validation for the CRD
+- op: add
+  path: /spec/versions/0/schema/openAPIV3Schema/properties/metadata/properties
+  value:
+    name:
+      type: string
+      x-kubernetes-validations:
+      - rule: 3 <= size(self) && size(self) <= 58
+        message: >-
+          custom validation:
+          template: must be between 3..58 characters,
+          linode instance: labels must be between 3..64 characters
+      - rule: self.matches('^[[:alnum:]]([-_.[:alnum:]]+[[:alnum:]])*$')
+        message: >-
+          custom validation:
+          linode instance: labels:
+          must begin and end with an alphanumeric character,
+          may only consist of alphanumeric characters, hyphens (-), underscores (_) or periods (.),
+          cannot have two hyphens (--), underscores (__) or periods (..) in a row,
+          regex used for validation is: '^[[:alnum:]]([-_.[:alnum:]]+[[:alnum:]])*$',
+          see: https://www.linode.com/docs/api/linode-instances/#linode-create
+      # TODO: Consider combining this into the regex above to minimize time complexity
+      # See: https://github.com/google/cel-spec/blob/master/doc/langdef.md#time-complexity
+      - rule: "!(self.contains('--') || self.contains('__') || self.contains('..'))"
+        message: >-
+          custom validation:
+          linode instance: labels cannot have two hyphens (--), underscores (__) or periods (..) in a row