pkg/controller/jobframework/workload_names.go

/*
Copyright 2023 The Kubernetes 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 jobframework

import (
	"crypto/sha1"
	"encoding/hex"
	"fmt"
	"strings"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime/schema"
)

const (
	hashLength = 5
	// 253 is the maximal length for a CRD name. We need to subtract one for '-', and the hash length.
	maxPrefixLength = 252 - hashLength
)

func GetWorkloadNameForOwnerRef(owner *metav1.OwnerReference) (string, error) {
	gv, err := schema.ParseGroupVersion(owner.APIVersion)
	if err != nil {
		return "", err
	}
	gvk := gv.WithKind(owner.Kind)
	return GetWorkloadNameForOwnerWithGVK(owner.Name, gvk), nil
}

func GetWorkloadNameForOwnerWithGVK(ownerName string, ownerGVK schema.GroupVersionKind) string {
	prefixedName := strings.ToLower(ownerGVK.Kind) + "-" + ownerName
	if len(prefixedName) > maxPrefixLength {
		prefixedName = prefixedName[:maxPrefixLength]
	}
	return prefixedName + "-" + getHash(ownerName, ownerGVK)[:hashLength]
}

func getHash(ownerName string, gvk schema.GroupVersionKind) string {
	h := sha1.New()
	h.Write([]byte(gvk.Kind))
	h.Write([]byte("\n"))
	h.Write([]byte(gvk.Group))
	h.Write([]byte("\n"))
	h.Write([]byte(ownerName))
	return hex.EncodeToString(h.Sum(nil))
}

func getOwnerKey(ownerGVK schema.GroupVersionKind) string {
	return fmt.Sprintf(".metadata.ownerReferences[%s.%s]", ownerGVK.Group, ownerGVK.Kind)
}