k3s/vendor/k8s.io/kubernetes/pkg/kubelet/config/file.go

246 lines
6.1 KiB
Go

/*
Copyright 2016 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 config
import (
"fmt"
"os"
"path/filepath"
"sort"
"strings"
"time"
"k8s.io/klog/v2"
"k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/types"
"k8s.io/client-go/tools/cache"
api "k8s.io/kubernetes/pkg/apis/core"
kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
utilio "k8s.io/utils/io"
)
type podEventType int
const (
podAdd podEventType = iota
podModify
podDelete
eventBufferLen = 10
)
type watchEvent struct {
fileName string
eventType podEventType
}
type sourceFile struct {
path string
nodeName types.NodeName
period time.Duration
store cache.Store
fileKeyMapping map[string]string
updates chan<- interface{}
watchEvents chan *watchEvent
}
// NewSourceFile watches a config file for changes.
func NewSourceFile(path string, nodeName types.NodeName, period time.Duration, updates chan<- interface{}) {
// "github.com/sigma/go-inotify" requires a path without trailing "/"
path = strings.TrimRight(path, string(os.PathSeparator))
config := newSourceFile(path, nodeName, period, updates)
klog.V(1).Infof("Watching path %q", path)
config.run()
}
func newSourceFile(path string, nodeName types.NodeName, period time.Duration, updates chan<- interface{}) *sourceFile {
send := func(objs []interface{}) {
var pods []*v1.Pod
for _, o := range objs {
pods = append(pods, o.(*v1.Pod))
}
updates <- kubetypes.PodUpdate{Pods: pods, Op: kubetypes.SET, Source: kubetypes.FileSource}
}
store := cache.NewUndeltaStore(send, cache.MetaNamespaceKeyFunc)
return &sourceFile{
path: path,
nodeName: nodeName,
period: period,
store: store,
fileKeyMapping: map[string]string{},
updates: updates,
watchEvents: make(chan *watchEvent, eventBufferLen),
}
}
func (s *sourceFile) run() {
listTicker := time.NewTicker(s.period)
go func() {
// Read path immediately to speed up startup.
if err := s.listConfig(); err != nil {
klog.Errorf("Unable to read config path %q: %v", s.path, err)
}
for {
select {
case <-listTicker.C:
if err := s.listConfig(); err != nil {
klog.Errorf("Unable to read config path %q: %v", s.path, err)
}
case e := <-s.watchEvents:
if err := s.consumeWatchEvent(e); err != nil {
klog.Errorf("Unable to process watch event: %v", err)
}
}
}
}()
s.startWatch()
}
func (s *sourceFile) applyDefaults(pod *api.Pod, source string) error {
return applyDefaults(pod, source, true, s.nodeName)
}
func (s *sourceFile) listConfig() error {
path := s.path
statInfo, err := os.Stat(path)
if err != nil {
if !os.IsNotExist(err) {
return err
}
// Emit an update with an empty PodList to allow FileSource to be marked as seen
s.updates <- kubetypes.PodUpdate{Pods: []*v1.Pod{}, Op: kubetypes.SET, Source: kubetypes.FileSource}
return fmt.Errorf("path does not exist, ignoring")
}
switch {
case statInfo.Mode().IsDir():
pods, err := s.extractFromDir(path)
if err != nil {
return err
}
if len(pods) == 0 {
// Emit an update with an empty PodList to allow FileSource to be marked as seen
s.updates <- kubetypes.PodUpdate{Pods: pods, Op: kubetypes.SET, Source: kubetypes.FileSource}
return nil
}
return s.replaceStore(pods...)
case statInfo.Mode().IsRegular():
pod, err := s.extractFromFile(path)
if err != nil {
return err
}
return s.replaceStore(pod)
default:
return fmt.Errorf("path is not a directory or file")
}
}
// Get as many pod manifests as we can from a directory. Return an error if and only if something
// prevented us from reading anything at all. Do not return an error if only some files
// were problematic.
func (s *sourceFile) extractFromDir(name string) ([]*v1.Pod, error) {
dirents, err := filepath.Glob(filepath.Join(name, "[^.]*"))
if err != nil {
return nil, fmt.Errorf("glob failed: %v", err)
}
pods := make([]*v1.Pod, 0)
if len(dirents) == 0 {
return pods, nil
}
sort.Strings(dirents)
for _, path := range dirents {
statInfo, err := os.Stat(path)
if err != nil {
klog.Errorf("Can't get metadata for %q: %v", path, err)
continue
}
switch {
case statInfo.Mode().IsDir():
klog.Errorf("Not recursing into manifest path %q", path)
case statInfo.Mode().IsRegular():
pod, err := s.extractFromFile(path)
if err != nil {
if !os.IsNotExist(err) {
klog.Errorf("Can't process manifest file %q: %v", path, err)
}
} else {
pods = append(pods, pod)
}
default:
klog.Errorf("Manifest path %q is not a directory or file: %v", path, statInfo.Mode())
}
}
return pods, nil
}
// extractFromFile parses a file for Pod configuration information.
func (s *sourceFile) extractFromFile(filename string) (pod *v1.Pod, err error) {
klog.V(3).Infof("Reading config file %q", filename)
defer func() {
if err == nil && pod != nil {
objKey, keyErr := cache.MetaNamespaceKeyFunc(pod)
if keyErr != nil {
err = keyErr
return
}
s.fileKeyMapping[filename] = objKey
}
}()
file, err := os.Open(filename)
if err != nil {
return pod, err
}
defer file.Close()
data, err := utilio.ReadAtMost(file, maxConfigLength)
if err != nil {
return pod, err
}
defaultFn := func(pod *api.Pod) error {
return s.applyDefaults(pod, filename)
}
parsed, pod, podErr := tryDecodeSinglePod(data, defaultFn)
if parsed {
if podErr != nil {
return pod, podErr
}
return pod, nil
}
return pod, fmt.Errorf("%v: couldn't parse as pod(%v), please check config file", filename, podErr)
}
func (s *sourceFile) replaceStore(pods ...*v1.Pod) (err error) {
objs := []interface{}{}
for _, pod := range pods {
objs = append(objs, pod)
}
return s.store.Replace(objs, "")
}