443d58e40a
Alpha implementation of the Dynamic Kubelet Configuration feature. See the proposal doc in #29459.
128 lines
3.3 KiB
Go
128 lines
3.3 KiB
Go
/*
|
|
Copyright 2017 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 startups
|
|
|
|
import (
|
|
"encoding/json"
|
|
"fmt"
|
|
"path/filepath"
|
|
"time"
|
|
|
|
utilfiles "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/files"
|
|
utilfs "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/filesystem"
|
|
utillog "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/log"
|
|
)
|
|
|
|
const (
|
|
startupsFile = "startups.json"
|
|
)
|
|
|
|
// fsTracker tracks startups in the local filesystem
|
|
type fsTracker struct {
|
|
// fs is the filesystem to use for storage operations; can be mocked for testing
|
|
fs utilfs.Filesystem
|
|
// trackingDir is the absolute path to the storage directory for fsTracker
|
|
trackingDir string
|
|
}
|
|
|
|
// NewFsTracker returns a Tracker that will store information in the `trackingDir`
|
|
func NewFsTracker(fs utilfs.Filesystem, trackingDir string) Tracker {
|
|
return &fsTracker{
|
|
fs: fs,
|
|
trackingDir: trackingDir,
|
|
}
|
|
}
|
|
|
|
func (tracker *fsTracker) Initialize() error {
|
|
utillog.Infof("initializing startups tracking directory %q", tracker.trackingDir)
|
|
if err := utilfiles.EnsureDir(tracker.fs, tracker.trackingDir); err != nil {
|
|
return err
|
|
}
|
|
if err := utilfiles.EnsureFile(tracker.fs, filepath.Join(tracker.trackingDir, startupsFile)); err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (tracker *fsTracker) RecordStartup() error {
|
|
// load the file
|
|
ls, err := tracker.load()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
ls = recordStartup(ls)
|
|
|
|
// save the file
|
|
err = tracker.save(ls)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (tracker *fsTracker) StartupsSince(t time.Time) (int32, error) {
|
|
// load the startups-tracking file
|
|
ls, err := tracker.load()
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
return startupsSince(ls, t)
|
|
}
|
|
|
|
// TODO(mtaufen): refactor into encode/decode like in badconfig.go
|
|
|
|
// load loads the startups-tracking file from disk
|
|
func (tracker *fsTracker) load() ([]string, error) {
|
|
path := filepath.Join(tracker.trackingDir, startupsFile)
|
|
|
|
// load the file
|
|
b, err := tracker.fs.ReadFile(path)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to load startups-tracking file %q, error: %v", path, err)
|
|
}
|
|
|
|
// parse json into the slice
|
|
ls := []string{}
|
|
|
|
// if the file is empty, just return empty slice
|
|
if len(b) == 0 {
|
|
return ls, nil
|
|
}
|
|
|
|
// otherwise unmarshal the json
|
|
if err := json.Unmarshal(b, &ls); err != nil {
|
|
return nil, fmt.Errorf("failed to unmarshal json from startups-tracking file %q, error: %v", path, err)
|
|
}
|
|
return ls, nil
|
|
}
|
|
|
|
// save replaces the contents of the startups-tracking file with `ls`
|
|
func (tracker *fsTracker) save(ls []string) error {
|
|
// marshal the json
|
|
b, err := json.Marshal(ls)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
// save the file
|
|
path := filepath.Join(tracker.trackingDir, startupsFile)
|
|
if err := utilfiles.ReplaceFile(tracker.fs, path, b); err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|