pod.go

/*
Copyright 2023 The Kubeflow 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 core

import (
	utillabels "github.com/dafu-wu/common/pkg/util/labels"

	apiv1 "github.com/dafu-wu/common/pkg/apis/common/v1"
	log "github.com/sirupsen/logrus"
	v1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/labels"
)

// FilterPodsForReplicaType returns pods belong to a replicaType.
func FilterPodsForReplicaType(pods []*v1.Pod, replicaType string) ([]*v1.Pod, error) {
	var result []*v1.Pod

	selector := labels.SelectorFromValidatedSet(labels.Set{
		apiv1.ReplicaTypeLabel: replicaType,
	})

	for _, pod := range pods {
		set := labels.Set(pod.Labels)
		if !selector.Matches(set) {
			continue
		}
		result = append(result, pod)
	}
	return result, nil
}

// GetPodSlices returns a slice, which element is the slice of pod.
// It gives enough information to caller to make decision to up/down scale resources.
func GetPodSlices(pods []*v1.Pod, replicas int, logger *log.Entry) [][]*v1.Pod {
	podSlices := make([][]*v1.Pod, CalculatePodSliceSize(pods, replicas))
	for _, pod := range pods {
		index, err := utillabels.ReplicaIndex(pod.Labels)
		if err != nil {
			logger.Warningf("Error obtaining replica index from Pod %s/%s: %v", pod.Namespace, pod.Name, err)
			continue
		}
		if index < 0 || index >= replicas {
			logger.Warningf("The label index is not expected: %d, pod: %s/%s", index, pod.Namespace, pod.Name)
		}

		podSlices[index] = append(podSlices[index], pod)
	}
	return podSlices
}

// CalculatePodSliceSize compare max pod index with desired replicas and return larger size
func CalculatePodSliceSize(pods []*v1.Pod, replicas int) int {
	size := 0
	for _, pod := range pods {
		index, err := utillabels.ReplicaIndex(pod.Labels)
		if err != nil {
			continue
		}
		size = MaxInt(size, index)
	}

	// size comes from index, need to +1 to indicate real size
	return MaxInt(size+1, replicas)
}

// SetRestartPolicy check the RestartPolicy defined in job spec and overwrite RestartPolicy in podTemplate if necessary
func SetRestartPolicy(podTemplateSpec *v1.PodTemplateSpec, spec *apiv1.ReplicaSpec) {
	// This is necessary since restartPolicyExitCode is not supported in v1.PodTemplateSpec
	if spec.RestartPolicy == apiv1.RestartPolicyExitCode {
		podTemplateSpec.Spec.RestartPolicy = v1.RestartPolicyNever
	} else {
		podTemplateSpec.Spec.RestartPolicy = v1.RestartPolicy(spec.RestartPolicy)
	}
}