karmada/pkg/util/selector.go

242 lines
8.2 KiB
Go

/*
Copyright 2021 The Karmada Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package util
import (
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/klog/v2"
"k8s.io/utils/strings/slices"
clusterv1alpha1 "github.com/karmada-io/karmada/pkg/apis/cluster/v1alpha1"
policyv1alpha1 "github.com/karmada-io/karmada/pkg/apis/policy/v1alpha1"
"github.com/karmada-io/karmada/pkg/util/lifted"
)
// ImplicitPriority describes the extent to which a ResourceSelector or a set of
// ResourceSelectors match resources.
type ImplicitPriority int
const (
// PriorityMisMatch means the ResourceSelector does not match the resource.
PriorityMisMatch ImplicitPriority = iota
// PriorityMatchAll means the ResourceSelector whose Name and LabelSelector is empty
// matches the resource.
PriorityMatchAll
// PriorityMatchLabelSelector means the LabelSelector of ResourceSelector matches the resource.
PriorityMatchLabelSelector
// PriorityMatchName means the Name of ResourceSelector matches the resource.
PriorityMatchName
)
// ResourceMatches tells if the specific resource matches the selector.
func ResourceMatches(resource *unstructured.Unstructured, rs policyv1alpha1.ResourceSelector) bool {
return ResourceSelectorPriority(resource, rs) > PriorityMisMatch
}
// ResourceSelectorPriority tells the priority between the specific resource and the selector.
func ResourceSelectorPriority(resource *unstructured.Unstructured, rs policyv1alpha1.ResourceSelector) ImplicitPriority {
if resource.GetAPIVersion() != rs.APIVersion ||
resource.GetKind() != rs.Kind ||
(len(rs.Namespace) > 0 && resource.GetNamespace() != rs.Namespace) {
return PriorityMisMatch
}
// match rules:
// case ResourceSelector.name ResourceSelector.labelSelector Rule
// 1 not-empty not-empty match name only and ignore selector
// 2 not-empty empty match name only
// 3 empty not-empty match selector only
// 4 empty empty match all
// case 1, 2: name not empty, don't need to consult selector.
if len(rs.Name) > 0 {
if rs.Name == resource.GetName() {
return PriorityMatchName
}
return PriorityMisMatch
}
// case 4: short path, both name and selector empty, matches all
if rs.LabelSelector == nil {
return PriorityMatchAll
}
// case 3: matches with selector
var s labels.Selector
var err error
if s, err = metav1.LabelSelectorAsSelector(rs.LabelSelector); err != nil {
// should not happen because all resource selector should be fully validated by webhook.
return PriorityMisMatch
}
if s.Matches(labels.Set(resource.GetLabels())) {
return PriorityMatchLabelSelector
}
return PriorityMisMatch
}
// ClusterMatches tells if specific cluster matches the affinity.
func ClusterMatches(cluster *clusterv1alpha1.Cluster, affinity policyv1alpha1.ClusterAffinity) bool {
for _, clusterName := range affinity.ExcludeClusters {
if clusterName == cluster.Name {
return false
}
}
// match rules:
// case LabelSelector ClusterNames FieldSelector Rule
// 1 not-empty not-empty not-empty match selector, name and field
// 2 not-empty empty empty match selector only
// 3 not-empty not-empty empty match selector, name
// 4 not-empty empty not-empty match selector, filed
// 5 empty not-empty not-empty match name, filed
// 6 empty not-empty empty match name only
// 7 empty empty not-empty match field only
// 8 empty empty empty match all
if affinity.LabelSelector != nil {
var s labels.Selector
var err error
if s, err = metav1.LabelSelectorAsSelector(affinity.LabelSelector); err != nil {
return false
}
if !s.Matches(labels.Set(cluster.GetLabels())) {
return false
}
}
if affinity.FieldSelector != nil {
var clusterFieldsMatchExpressions []corev1.NodeSelectorRequirement
for i := range affinity.FieldSelector.MatchExpressions {
matchExpression := &affinity.FieldSelector.MatchExpressions[i]
if matchExpression.Key != ZoneField {
clusterFieldsMatchExpressions = append(clusterFieldsMatchExpressions, *matchExpression)
continue
}
// First, match zones field.
if !matchZones(matchExpression, cluster.Spec.Zones) {
return false
}
}
if len(clusterFieldsMatchExpressions) > 0 {
// Second, match other fields.
var matchFields labels.Selector
var errs []error
if matchFields, errs = lifted.NodeSelectorRequirementsAsSelector(clusterFieldsMatchExpressions); errs != nil {
return false
}
clusterFields := extractClusterFields(cluster)
if matchFields != nil && !matchFields.Matches(clusterFields) {
return false
}
}
}
return ClusterNamesMatches(cluster, affinity.ClusterNames)
}
// ClusterNamesMatches tells if specific cluster matches the clusterNames affinity.
func ClusterNamesMatches(cluster *clusterv1alpha1.Cluster, clusterNames []string) bool {
if len(clusterNames) == 0 {
return true
}
for _, clusterName := range clusterNames {
if clusterName == cluster.Name {
return true
}
}
return false
}
// ResourceMatchSelectors tells if the specific resource matches the selectors.
func ResourceMatchSelectors(resource *unstructured.Unstructured, selectors ...policyv1alpha1.ResourceSelector) bool {
for _, rs := range selectors {
if ResourceMatches(resource, rs) {
return true
}
}
return false
}
// ResourceMatchSelectorsPriority returns the highest priority between specific resource and the selectors.
func ResourceMatchSelectorsPriority(resource *unstructured.Unstructured, selectors ...policyv1alpha1.ResourceSelector) ImplicitPriority {
var priority ImplicitPriority
for _, rs := range selectors {
if p := ResourceSelectorPriority(resource, rs); p > priority {
priority = p
}
}
return priority
}
func extractClusterFields(cluster *clusterv1alpha1.Cluster) labels.Set {
clusterFieldsMap := make(labels.Set)
if cluster.Spec.Provider != "" {
clusterFieldsMap[ProviderField] = cluster.Spec.Provider
}
if cluster.Spec.Region != "" {
clusterFieldsMap[RegionField] = cluster.Spec.Region
}
return clusterFieldsMap
}
// matchZones checks if zoneMatchExpression can match zones and returns true if it matches.
// For unknown operators, matchZones always returns false.
// The matching rules are as follows:
// 1. When the operator is "In", zoneMatchExpression must contain all zones, otherwise it doesn't match.
// 2. When the operator is "NotIn", zoneMatchExpression mustn't contain any one of zones, otherwise it doesn't match.
// 3. When the operator is "Exists", zones mustn't be empty, otherwise it doesn't match.
// 4. When the operator is "DoesNotExist", zones must be empty, otherwise it doesn't match.
func matchZones(zoneMatchExpression *corev1.NodeSelectorRequirement, zones []string) bool {
switch zoneMatchExpression.Operator {
case corev1.NodeSelectorOpIn:
if len(zones) == 0 {
return false
}
for _, zone := range zones {
if !slices.Contains(zoneMatchExpression.Values, zone) {
return false
}
}
return true
case corev1.NodeSelectorOpNotIn:
for _, zone := range zones {
if slices.Contains(zoneMatchExpression.Values, zone) {
return false
}
}
return true
case corev1.NodeSelectorOpExists:
return len(zones) > 0
case corev1.NodeSelectorOpDoesNotExist:
return len(zones) == 0
default:
klog.V(5).Infof("Unsupported %q operator for zones requirement", zoneMatchExpression.Operator)
return false
}
}