Description of problem:
Add template validation rule which should be skipped if a field is missing.

{
            "name": "core-limits",
            "valid": "jsonpath::.spec.domain.cpu.cores",
            "path": "jsonpath::.spec.domain.cpu.cores",
            "rule": "integer",
            "message": "cpu cores must be limited",
            "min": 1,
            "max": 8
        }

If a VM is created without the validated field (spec.domain.cpu.cores), template validator does not skip the rule and VM creation fails.

Version-Release number of selected component (if applicable):
CNV 2.4.1
Template validator 2.4.1-2

How reproducible:
100%

Steps to Reproduce:
1. Create a custom template
2. Add validation rule on a field (for example: cpu.cores)
3. Create a VM from the template (VM should not have cpu.cores)

Actual results:
VM creation fails

The request is invalid: .spec.domain.cpu.cores: cpu cores must be limited: Some of values [0] are not in interval [1, 8]

{"component":"kubevirt-template-validator","level":"info","msg":"evalution summary for win-16-1:\nminimal-required-memory applied: OK, All values [4294967296] are in interval [536870912, N/A]\nwindows-virtio-bus SKIPPED: not appliable\nwindows-disk-bus SKIPPED: not appliable\nwindows-cd-bus SKIPPED: not appliable\ncore-limits applied: FAIL, Some of values [0] are not in interval [1, 8]\n\nsucceeded=false","pos":"admission.go:42","timestamp":"2020-08-20T10:10:26.104309Z"}

When the rule contains wildcard usage ("valid": "jsonpath::.spec.domain.cpu.cores[*]")
The rule is skipped, however wildcards should apply on slices (i.e items with fields) and not fields.



Expected results:
VM creation should succeed, the rule should be skipped:

{"component":"kubevirt-template-validator","level":"info","msg":"evalution summary for win-16-1:\nminimal-required-memory applied: OK, All values [4294967296] are in interval [536870912, N/A]\nwindows-virtio-bus SKIPPED: not appliable\nwindows-disk-bus SKIPPED: not appliable\nwindows-cd-bus SKIPPED: not appliable\ncore-limits SKIPPED: not appliable\n\nsucceeded=true","pos":"admission.go:42","timestamp":"2020-08-20T10:09:31.777678Z"}


Additional info:

=====================================================
$ oc get -n openshift template -n openshift windows-server-medium-v0.11.3-new -oyaml
apiVersion: template.openshift.io/v1
kind: Template
metadata:
  annotations:
    defaults.template.kubevirt.io/disk: rootdisk
    defaults.template.kubevirt.io/network: default
    description: Template for Microsoft Windows Server 2012 R2 VM or newer. A PVC
      with the Windows disk image must be available.
    iconClass: icon-windows
    name.os.template.kubevirt.io/win2k12r2: Microsoft Windows Server 2012 R2
    name.os.template.kubevirt.io/win2k16: Microsoft Windows Server 2016
    name.os.template.kubevirt.io/win2k19: Microsoft Windows Server 2019
    openshift.io/display-name: Microsoft Windows Server 2012 R2+ VM
    openshift.io/documentation-url: https://github.com/kubevirt/common-templates
    openshift.io/provider-display-name: KubeVirt
    openshift.io/support-url: https://github.com/kubevirt/common-templates/issues
    tags: hidden,kubevirt,virtualmachine,windows
    template.kubevirt.io/editable: |
      /objects[0].spec.template.spec.domain.cpu.cores
      /objects[0].spec.template.spec.domain.resources.requests.memory
      /objects[0].spec.template.spec.domain.devices.disks
      /objects[0].spec.template.spec.volumes
      /objects[0].spec.template.spec.networks
    template.kubevirt.io/version: v1alpha1
    template.openshift.io/bindable: "false"
    validations: |
      [
        {
          "name": "minimal-required-memory",
          "path": "jsonpath::.spec.domain.resources.requests.memory",
          "rule": "integer",
          "message": "This VM requires more memory.",
          "min": 536870912
        }, {
          "name": "windows-virtio-bus",
          "path": "jsonpath::.spec.domain.devices.disks[*].disk.bus",
          "valid": "jsonpath::.spec.domain.devices.disks[*]",
          "rule": "enum",
          "message": "virto disk bus type has better performance, install virtio drivers in VM and change bus type",
          "values": ["virtio"],
          "justWarning": true
        }, {
          "name": "windows-disk-bus",
          "path": "jsonpath::.spec.domain.devices.disks[*].disk.bus",
          "valid": "jsonpath::.spec.domain.devices.disks[*]",
          "rule": "enum",
          "message": "disk bus has to be either virtio or sata",
          "values": ["virtio", "sata"]
        }, {
          "name": "windows-cd-bus",
          "path": "jsonpath::.spec.domain.devices.disks[*].cdrom.bus",
          "valid": "jsonpath::.spec.domain.devices.disks[*].cdrom.bus",
          "rule": "enum",
          "message": "cd bus has to be sata",
          "values": ["sata"]
        }, {
            "name": "core-limits",
            "valid": "jsonpath::.spec.domain.cpu.cores",
            "path": "jsonpath::.spec.domain.cpu.cores",
            "rule": "integer",
            "message": "cpu cores must be limited",
            "min": 1,
            "max": 8
        }
      ]
  creationTimestamp: "2020-08-20T08:24:03Z"
  labels:
    flavor.template.kubevirt.io/medium: "true"
    os.template.kubevirt.io/win2k12r2: "true"
    os.template.kubevirt.io/win2k16: "true"
    os.template.kubevirt.io/win2k19: "true"
    template.kubevirt.io/type: base
    template.kubevirt.io/version: v0.11.3
    workload.template.kubevirt.io/server: "true"
  managedFields:
  - apiVersion: template.openshift.io/v1
    fieldsType: FieldsV1
    fieldsV1:
      f:metadata:
        f:ownerReferences:
          .: {}
          k:{"uid":"e0330a3c-028d-4ff0-ae9a-baff858a44ac"}:
            .: {}
            f:apiVersion: {}
            f:kind: {}
            f:name: {}
            f:uid: {}
    manager: Swagger-Codegen
    operation: Update
    time: "2020-08-20T07:14:23Z"
  - apiVersion: template.openshift.io/v1
    fieldsType: FieldsV1
    fieldsV1:
      f:metadata:
        f:annotations:
          .: {}
          f:defaults.template.kubevirt.io/disk: {}
          f:defaults.template.kubevirt.io/network: {}
          f:description: {}
          f:iconClass: {}
          f:name.os.template.kubevirt.io/win2k12r2: {}
          f:name.os.template.kubevirt.io/win2k16: {}
          f:name.os.template.kubevirt.io/win2k19: {}
          f:openshift.io/display-name: {}
          f:openshift.io/documentation-url: {}
          f:openshift.io/provider-display-name: {}
          f:openshift.io/support-url: {}
          f:tags: {}
          f:template.kubevirt.io/editable: {}
          f:template.kubevirt.io/version: {}
          f:template.openshift.io/bindable: {}
          f:validations: {}
        f:labels:
          .: {}
          f:flavor.template.kubevirt.io/medium: {}
          f:os.template.kubevirt.io/win2k12r2: {}
          f:os.template.kubevirt.io/win2k16: {}
          f:os.template.kubevirt.io/win2k19: {}
          f:template.kubevirt.io/type: {}
          f:template.kubevirt.io/version: {}
          f:workload.template.kubevirt.io/server: {}
      f:objects: {}
      f:parameters: {}
    manager: oc
    operation: Update
    time: "2020-08-20T10:10:23Z"
  name: windows-server-medium-v0.11.3-new
  namespace: openshift
  resourceVersion: "173734"
  selfLink: /apis/template.openshift.io/v1/namespaces/openshift/templates/windows-server-medium-v0.11.3-new
  uid: b83a89ec-633e-49f6-bc62-9df58ae23c93
objects:
- apiVersion: kubevirt.io/v1alpha3
  kind: VirtualMachine
  metadata:
    labels:
      app: ${NAME}
      vm.kubevirt.io/template: windows-server-medium-v0.11.3-new
      vm.kubevirt.io/template.revision: "1"
      vm.kubevirt.io/template.version: v0.11.3
    name: ${NAME}
  spec:
    running: false
    template:
      metadata:
        labels:
          kubevirt.io/domain: ${NAME}
          kubevirt.io/size: medium
      spec:
        domain:
          clock:
            timer:
              hpet:
                present: false
              hyperv: {}
              pit:
                tickPolicy: delay
              rtc:
                tickPolicy: catchup
            utc: {}
          cpu:
            cores: 1
            sockets: 1
            threads: 1
          devices:
            disks:
            - disk:
                bus: sata
              name: rootdisk
            inputs:
            - bus: usb
              name: tablet
              type: tablet
            interfaces:
            - masquerade: {}
              model: e1000e
              name: default
          features:
            acpi: {}
            apic: {}
            hyperv:
              relaxed: {}
              spinlocks:
                spinlocks: 8191
              vapic: {}
          resources:
            requests:
              memory: 4Gi
        evictionStrategy: LiveMigrate
        networks:
        - name: default
          pod: {}
        terminationGracePeriodSeconds: 3600
        volumes:
        - name: rootdisk
          persistentVolumeClaim:
            claimName: ${PVCNAME}
parameters:
- description: VM name
  from: windows-[a-z0-9]{6}
  generate: expression
  name: NAME
- description: Name of the PVC with the disk image
  name: PVCNAME
  required: true


=====================================================
VM.yaml:
apiVersion: v1
items:
- apiVersion: kubevirt.io/v1alpha3
  kind: VirtualMachine
  metadata:
    labels:
      app: win-16-1
      vm.kubevirt.io/template: windows-server-medium-v0.11.3-new
      vm.kubevirt.io/template.namespace: openshift
      vm.kubevirt.io/template.revision: "1"
      vm.kubevirt.io/template.version: v0.11.3
    name: win-16-1
  spec:
    running: false
    template:
      metadata:
        labels:
          kubevirt.io/domain: win-16-1
          kubevirt.io/size: medium
      spec:
        domain:
          clock:
            timer:
              hpet:
                present: false
              hyperv: {}
              pit:
                tickPolicy: delay
              rtc:
                tickPolicy: catchup
            utc: {}
          cpu:
            sockets: 1
            threads: 1
          devices:
            inputs:
            - bus: usb
              name: tablet
              type: tablet
            interfaces:
            - masquerade: {}
              model: e1000e
              name: default
          features:
            acpi: {}
            apic: {}
            hyperv:
              relaxed: {}
              spinlocks:
                spinlocks: 8191
              vapic: {}
          machine:
            type: pc-q35-rhel8.2.0
          resources:
            requests:
              memory: 4Gi
        evictionStrategy: LiveMigrate
        networks:
        - name: default
          pod: {}
        terminationGracePeriodSeconds: 3600
        volumes:
        - name: rootdisk
          persistentVolumeClaim:
            claimName: win-16-1
kind: List
metadata: {}