k3s/pkg/master/pod_cache.go

96 lines
2.8 KiB
Go

/*
Copyright 2014 Google Inc. 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
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 master
import (
"sync"
"time"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
"github.com/GoogleCloudPlatform/kubernetes/pkg/registry/pod"
"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
"github.com/golang/glog"
)
// PodCache contains both a cache of container information, as well as the mechanism for keeping
// that cache up to date.
type PodCache struct {
containerInfo client.PodInfoGetter
pods pod.Registry
// This is a map of pod id to a map of container name to the
podInfo map[string]api.PodInfo
period time.Duration
podLock sync.Mutex
}
// NewPodCache returns a new PodCache which watches container information registered in the given PodRegistry.
func NewPodCache(info client.PodInfoGetter, pods pod.Registry, period time.Duration) *PodCache {
return &PodCache{
containerInfo: info,
pods: pods,
podInfo: map[string]api.PodInfo{},
period: period,
}
}
// GetPodInfo Implements the PodInfoGetter.GetPodInfo.
// The returned value should be treated as read-only.
func (p *PodCache) GetPodInfo(host, podID string) (api.PodInfo, error) {
p.podLock.Lock()
defer p.podLock.Unlock()
value, ok := p.podInfo[podID]
if !ok {
return nil, client.ErrPodInfoNotAvailable
}
return value, nil
}
func (p *PodCache) updatePodInfo(host, id string) error {
info, err := p.containerInfo.GetPodInfo(host, id)
if err != nil {
return err
}
p.podLock.Lock()
defer p.podLock.Unlock()
p.podInfo[id] = info
return nil
}
// UpdateAllContainers updates information about all containers. Either called by Loop() below, or one-off.
func (p *PodCache) UpdateAllContainers() {
pods, err := p.pods.ListPods(labels.Everything())
if err != nil {
glog.Errorf("Error synchronizing container list: %v", err)
return
}
for _, pod := range pods {
err := p.updatePodInfo(pod.CurrentState.Host, pod.ID)
if err != nil && err != client.ErrPodInfoNotAvailable {
glog.Errorf("Error synchronizing container: %v", err)
}
}
}
// Loop begins watching updates of container information.
// It runs forever, and is expected to be placed in a go routine.
func (p *PodCache) Loop() {
util.Forever(func() { p.UpdateAllContainers() }, p.period)
}