strategy.go

/*
 * Tencent is pleased to support the open source community by making TKEStack
 * available.
 *
 * Copyright (C) 2012-2019 Tencent. All Rights Reserved.
 *
 * 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
 *
 * https://opensource.org/licenses/Apache-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 OF ANY KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations under the License.
 */

package rule

import (
	"context"
	"fmt"

	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/util/validation/field"
	"k8s.io/apiserver/pkg/registry/rest"
	"k8s.io/apiserver/pkg/storage/names"

	"k8s.io/apimachinery/pkg/fields"
	"k8s.io/apimachinery/pkg/labels"
	"k8s.io/apiserver/pkg/registry/generic"
	"k8s.io/apiserver/pkg/storage"

	"tkestack.io/tke/api/auth"
	namesutil "tkestack.io/tke/pkg/util/names"
)

// Strategy implements verification logic for rule.
type Strategy struct {
	runtime.ObjectTyper
	names.NameGenerator
}

// NewStrategy creates a strategy that is the default logic that applies when
// creating and updating rule objects.
func NewStrategy() *Strategy {
	return &Strategy{auth.Scheme, namesutil.Generator}
}

// DefaultGarbageCollectionRule returns the default garbage collection behavior.
func (Strategy) DefaultGarbageCollectionRule(ctx context.Context) rest.GarbageCollectionPolicy {
	return rest.Unsupported
}

// PrepareForUpdate is invoked on update before validation to normalize the
// object.
func (Strategy) PrepareForUpdate(ctx context.Context, obj, old runtime.Object) {
}

// NamespaceScoped is false for policies.
func (Strategy) NamespaceScoped() bool {
	return false
}

// PrepareForCreate is invoked on create before validation to normalize
// the object.
func (Strategy) PrepareForCreate(ctx context.Context, obj runtime.Object) {
	rule, _ := obj.(*auth.Rule)

	if rule.Name == "" && rule.GenerateName == "" {
		rule.GenerateName = "rul-"
	}
}

// Validate validates a new rule.
func (Strategy) Validate(ctx context.Context, obj runtime.Object) field.ErrorList {
	return ValidateRule(obj.(*auth.Rule))
}

// AllowCreateOnUpdate is false for policies.
func (Strategy) AllowCreateOnUpdate() bool {
	return false
}

// AllowUnconditionalUpdate returns true if the object can be updated
// unconditionally (irrespective of the latest resource version), when there is
// no resource version specified in the object.
func (Strategy) AllowUnconditionalUpdate() bool {
	return false
}

// WarningsOnCreate returns warnings for the creation of the given object.
func (Strategy) WarningsOnCreate(ctx context.Context, obj runtime.Object) []string {
	return nil
}

// Canonicalize normalizes the object after validation.
func (Strategy) Canonicalize(obj runtime.Object) {
}

// ValidateUpdate is the default update validation for an end rule.
func (Strategy) ValidateUpdate(ctx context.Context, obj, old runtime.Object) field.ErrorList {
	return ValidateRuleUpdate(obj.(*auth.Rule), old.(*auth.Rule))
}

// GetAttrs returns labels and fields of a given object for filtering purposes.
func GetAttrs(obj runtime.Object) (labels.Set, fields.Set, error) {
	rule, ok := obj.(*auth.Rule)
	if !ok {
		return nil, nil, fmt.Errorf("not a rule")
	}
	return rule.ObjectMeta.Labels, ToSelectableFields(rule), nil
}

// MatchRule returns a generic matcher for a given label and field selector.
func MatchRule(label labels.Selector, field fields.Selector) storage.SelectionPredicate {
	return storage.SelectionPredicate{
		Label:    label,
		Field:    field,
		GetAttrs: GetAttrs,
		IndexFields: []string{
			"spec.ptype",
			"spec.v0",
			"spec.v1",
			"spec.v2",
			"spec.v3",
			"spec.v4",
			"spec.v5",
			"spec.v6",
		},
	}
}

// ToSelectableFields returns a field set that represents the object
func ToSelectableFields(rule *auth.Rule) fields.Set {
	objectMetaFieldsSet := generic.ObjectMetaFieldsSet(&rule.ObjectMeta, false)
	specificFieldsSet := fields.Set{
		"spec.ptype": rule.Spec.PType,
		"spec.v0":    rule.Spec.V0,
		"spec.v1":    rule.Spec.V1,
		"spec.v2":    rule.Spec.V2,
		"spec.v3":    rule.Spec.V3,
		"spec.v4":    rule.Spec.V4,
		"spec.v5":    rule.Spec.V5,
		"spec.v6":    rule.Spec.V6,
	}
	return generic.MergeFieldsSets(objectMetaFieldsSet, specificFieldsSet)
}