karmada/pkg/util/overridemanager/overridemanager.go

237 lines
8.3 KiB
Go

package overridemanager
import (
"context"
"encoding/json"
"github.com/evanphx/json-patch/v5"
"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
"k8s.io/klog/v2"
"sigs.k8s.io/controller-runtime/pkg/client"
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"
)
// OverrideManager managers override policies operation
type OverrideManager interface {
// ApplyOverridePolicies overrides the object if one or more override policies exist and matches the target cluster.
// For cluster scoped resource:
// - Apply ClusterOverridePolicy by policies name in ascending
// For namespaced scoped resource, apply order is:
// - First apply ClusterOverridePolicy;
// - Then apply OverridePolicy;
ApplyOverridePolicies(rawObj *unstructured.Unstructured, cluster string) (appliedClusterPolicies *AppliedOverrides, appliedNamespacedPolicies *AppliedOverrides, err error)
}
type overrideOption struct {
Op string `json:"op"`
Path string `json:"path"`
Value interface{} `json:"value,omitempty"`
}
type overrideManagerImpl struct {
client.Client
}
// New builds an OverrideManager instance.
func New(client client.Client) OverrideManager {
return &overrideManagerImpl{
Client: client,
}
}
func (o *overrideManagerImpl) ApplyOverridePolicies(rawObj *unstructured.Unstructured, clusterName string) (*AppliedOverrides, *AppliedOverrides, error) {
clusterObj := &clusterv1alpha1.Cluster{}
if err := o.Client.Get(context.TODO(), client.ObjectKey{Name: clusterName}, clusterObj); err != nil {
klog.Errorf("Failed to get member cluster: %s, error: %v", clusterName, err)
return nil, nil, err
}
var appliedClusterOverrides *AppliedOverrides
var appliedNamespacedOverrides *AppliedOverrides
var err error
// Apply cluster scoped override policies
appliedClusterOverrides, err = o.applyClusterOverrides(rawObj, clusterObj)
if err != nil {
klog.Errorf("Failed to apply cluster override policies. error: %v", err)
return nil, nil, err
}
// For namespace scoped resources, should apply override policies under the same namespace.
// No matter the resources propagated by ClusterPropagationPolicy or PropagationPolicy.
if len(rawObj.GetNamespace()) > 0 {
// Apply namespace scoped override policies
appliedNamespacedOverrides, err = o.applyNamespacedOverrides(rawObj, clusterObj)
if err != nil {
klog.Errorf("Failed to apply namespaced override policies. error: %v", err)
return nil, nil, err
}
}
return appliedClusterOverrides, appliedNamespacedOverrides, nil
}
// applyClusterOverrides will apply overrides according to ClusterOverridePolicy instructions.
func (o *overrideManagerImpl) applyClusterOverrides(rawObj *unstructured.Unstructured, cluster *clusterv1alpha1.Cluster) (*AppliedOverrides, error) {
// get all cluster-scoped override policies
policyList := &policyv1alpha1.ClusterOverridePolicyList{}
if err := o.Client.List(context.TODO(), policyList, &client.ListOptions{}); err != nil {
klog.Errorf("Failed to list cluster override policies, error: %v", err)
return nil, err
}
if len(policyList.Items) == 0 {
return nil, nil
}
matchedPolicies := o.getMatchedClusterOverridePolicy(policyList.Items, rawObj, cluster)
if len(matchedPolicies) == 0 {
klog.V(2).Infof("No cluster override policy for resource: %s/%s", rawObj.GetNamespace(), rawObj.GetName())
return nil, nil
}
appliedList := &AppliedOverrides{}
for _, p := range matchedPolicies {
if err := applyJSONPatch(rawObj, parseJSONPatch(p.Spec.Overriders.Plaintext)); err != nil {
return nil, err
}
klog.V(2).Infof("Applied cluster overrides(%s) for %s/%s", p.Name, rawObj.GetNamespace(), rawObj.GetName())
appliedList.Add(p.Name, p.Spec.Overriders)
}
return appliedList, nil
}
// applyNamespacedOverrides will apply overrides according to OverridePolicy instructions.
func (o *overrideManagerImpl) applyNamespacedOverrides(rawObj *unstructured.Unstructured, cluster *clusterv1alpha1.Cluster) (*AppliedOverrides, error) {
// get all namespace-scoped override policies
policyList := &policyv1alpha1.OverridePolicyList{}
if err := o.Client.List(context.TODO(), policyList, &client.ListOptions{Namespace: rawObj.GetNamespace()}); err != nil {
klog.Errorf("Failed to list override policies from namespace: %s, error: %v", rawObj.GetNamespace(), err)
return nil, err
}
if len(policyList.Items) == 0 {
return nil, nil
}
matchedPolicies := o.getMatchedOverridePolicy(policyList.Items, rawObj, cluster)
if len(matchedPolicies) == 0 {
klog.V(2).Infof("No override policy for resource: %s/%s", rawObj.GetNamespace(), rawObj.GetName())
return nil, nil
}
appliedList := &AppliedOverrides{}
for _, p := range matchedPolicies {
if err := applyJSONPatch(rawObj, parseJSONPatch(p.Spec.Overriders.Plaintext)); err != nil {
return nil, err
}
klog.V(2).Infof("Applied overrides(%s/%s) for %s/%s", p.Namespace, p.Name, rawObj.GetNamespace(), rawObj.GetName())
appliedList.Add(p.Name, p.Spec.Overriders)
}
return appliedList, nil
}
func (o *overrideManagerImpl) getMatchedClusterOverridePolicy(policies []policyv1alpha1.ClusterOverridePolicy, resource *unstructured.Unstructured, cluster *clusterv1alpha1.Cluster) []policyv1alpha1.ClusterOverridePolicy {
// select policy in which at least one resource selector matches target resource.
resourceMatches := make([]policyv1alpha1.ClusterOverridePolicy, 0)
for _, policy := range policies {
if OverridePolicyMatches(resource, policy.Spec.ResourceSelectors) {
resourceMatches = append(resourceMatches, policy)
}
}
// select policy which cluster selector matches target resource.
clusterMatches := make([]policyv1alpha1.ClusterOverridePolicy, 0)
for _, policy := range resourceMatches {
if util.ClusterMatches(cluster, policy.Spec.TargetCluster) {
clusterMatches = append(clusterMatches, policy)
}
}
// select policy in which at least one PlaintextOverrider matches target resource.
// TODO(RainbowMango): check if the overrider instructions can be applied to target resource.
// TODO(RainbowMango): Sort by policy names.
return clusterMatches
}
func (o *overrideManagerImpl) getMatchedOverridePolicy(policies []policyv1alpha1.OverridePolicy, resource *unstructured.Unstructured, cluster *clusterv1alpha1.Cluster) []policyv1alpha1.OverridePolicy {
// select policy in which at least one resource selector matches target resource.
resourceMatches := make([]policyv1alpha1.OverridePolicy, 0)
for _, policy := range policies {
if OverridePolicyMatches(resource, policy.Spec.ResourceSelectors) {
resourceMatches = append(resourceMatches, policy)
}
}
// select policy which cluster selector matches target resource.
clusterMatches := make([]policyv1alpha1.OverridePolicy, 0)
for _, policy := range resourceMatches {
if util.ClusterMatches(cluster, policy.Spec.TargetCluster) {
clusterMatches = append(clusterMatches, policy)
}
}
// select policy in which at least one PlaintextOverrider matches target resource.
// TODO(RainbowMango): check if the overrider instructions can be applied to target resource.
// TODO(RainbowMango): Sort by policy names.
return clusterMatches
}
func parseJSONPatch(overriders []policyv1alpha1.PlaintextOverrider) []overrideOption {
patches := make([]overrideOption, 0, len(overriders))
for i := range overriders {
patches = append(patches, overrideOption{
Op: string(overriders[i].Operator),
Path: overriders[i].Path,
Value: overriders[i].Value,
})
}
return patches
}
// applyJSONPatch applies the override on to the given unstructured object.
func applyJSONPatch(obj *unstructured.Unstructured, overrides []overrideOption) error {
jsonPatchBytes, err := json.Marshal(overrides)
if err != nil {
return err
}
patch, err := jsonpatch.DecodePatch(jsonPatchBytes)
if err != nil {
return err
}
objectJSONBytes, err := obj.MarshalJSON()
if err != nil {
return err
}
patchedObjectJSONBytes, err := patch.Apply(objectJSONBytes)
if err != nil {
return err
}
err = obj.UnmarshalJSON(patchedObjectJSONBytes)
return err
}
// OverridePolicyMatches tells if the override policy should be applied to the resource.
func OverridePolicyMatches(resource *unstructured.Unstructured, resourceSelector []policyv1alpha1.ResourceSelector) bool {
for _, rs := range resourceSelector {
if util.ResourceMatches(resource, rs) {
return true
}
}
return false
}