mirror of https://github.com/k3s-io/k3s
195 lines
4.7 KiB
Go
195 lines
4.7 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 generic
|
|
|
|
import (
|
|
"fmt"
|
|
"strings"
|
|
"time"
|
|
|
|
"github.com/sirupsen/logrus"
|
|
|
|
"k8s.io/apimachinery/pkg/api/meta"
|
|
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
|
|
"k8s.io/apimachinery/pkg/runtime"
|
|
utilruntime "k8s.io/apimachinery/pkg/util/runtime"
|
|
"k8s.io/apimachinery/pkg/util/wait"
|
|
"k8s.io/client-go/tools/cache"
|
|
"k8s.io/client-go/util/workqueue"
|
|
)
|
|
|
|
type Handler func(key string, obj runtime.Object) (runtime.Object, error)
|
|
|
|
// Controller is the controller implementation for Foo resources
|
|
type Controller struct {
|
|
name string
|
|
workqueue workqueue.RateLimitingInterface
|
|
informer cache.SharedIndexInformer
|
|
handler Handler
|
|
}
|
|
|
|
type generationKey struct {
|
|
generation int
|
|
key string
|
|
}
|
|
|
|
// NewController returns a new sample controller
|
|
func NewController(name string, informer cache.SharedIndexInformer, workqueue workqueue.RateLimitingInterface, handler Handler) *Controller {
|
|
controller := &Controller{
|
|
name: name,
|
|
handler: handler,
|
|
informer: informer,
|
|
workqueue: workqueue,
|
|
}
|
|
|
|
logrus.Info("Setting up event handlers")
|
|
informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
|
|
AddFunc: controller.handleObject,
|
|
UpdateFunc: func(old, new interface{}) {
|
|
newMeta, err := meta.Accessor(new)
|
|
utilruntime.Must(err)
|
|
oldMeta, err := meta.Accessor(old)
|
|
utilruntime.Must(err)
|
|
if newMeta.GetResourceVersion() == oldMeta.GetResourceVersion() {
|
|
return
|
|
}
|
|
controller.handleObject(new)
|
|
},
|
|
DeleteFunc: controller.handleObject,
|
|
})
|
|
|
|
return controller
|
|
}
|
|
|
|
func (c *Controller) run(threadiness int, stopCh <-chan struct{}) {
|
|
defer utilruntime.HandleCrash()
|
|
defer c.workqueue.ShutDown()
|
|
|
|
// Start the informer factories to begin populating the informer caches
|
|
logrus.Infof("Starting %s controller", c.name)
|
|
|
|
// Launch two workers to process Foo resources
|
|
for i := 0; i < threadiness; i++ {
|
|
go wait.Until(c.runWorker, time.Second, stopCh)
|
|
}
|
|
|
|
<-stopCh
|
|
logrus.Infof("Shutting down %s workers", c.name)
|
|
}
|
|
|
|
func (c *Controller) Run(threadiness int, stopCh <-chan struct{}) error {
|
|
if ok := cache.WaitForCacheSync(stopCh, c.informer.HasSynced); !ok {
|
|
c.workqueue.ShutDown()
|
|
return fmt.Errorf("failed to wait for caches to sync")
|
|
}
|
|
|
|
go c.run(threadiness, stopCh)
|
|
return nil
|
|
}
|
|
|
|
func (c *Controller) runWorker() {
|
|
for c.processNextWorkItem() {
|
|
}
|
|
}
|
|
|
|
func (c *Controller) processNextWorkItem() bool {
|
|
obj, shutdown := c.workqueue.Get()
|
|
|
|
if shutdown {
|
|
return false
|
|
}
|
|
|
|
if err := c.processSingleItem(obj); err != nil {
|
|
if !strings.Contains(err.Error(), "please apply your changes to the latest version and try again") {
|
|
utilruntime.HandleError(err)
|
|
}
|
|
return true
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
func (c *Controller) processSingleItem(obj interface{}) error {
|
|
var (
|
|
key string
|
|
ok bool
|
|
)
|
|
|
|
defer c.workqueue.Done(obj)
|
|
|
|
if key, ok = obj.(string); !ok {
|
|
c.workqueue.Forget(obj)
|
|
utilruntime.HandleError(fmt.Errorf("expected string in workqueue but got %#v", obj))
|
|
return nil
|
|
}
|
|
if err := c.syncHandler(key); err != nil {
|
|
c.workqueue.AddRateLimited(key)
|
|
return fmt.Errorf("error syncing '%s': %s, requeuing", key, err.Error())
|
|
}
|
|
|
|
c.workqueue.Forget(obj)
|
|
return nil
|
|
}
|
|
|
|
func (c *Controller) syncHandler(key string) error {
|
|
obj, exists, err := c.informer.GetStore().GetByKey(key)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if !exists {
|
|
_, err := c.handler(key, nil)
|
|
return err
|
|
}
|
|
|
|
_, err = c.handler(key, obj.(runtime.Object))
|
|
return err
|
|
}
|
|
|
|
func (c *Controller) Enqueue(namespace, name string) {
|
|
if namespace == "" {
|
|
c.workqueue.AddRateLimited(name)
|
|
} else {
|
|
c.workqueue.AddRateLimited(namespace + "/" + name)
|
|
}
|
|
}
|
|
|
|
func (c *Controller) enqueue(obj interface{}) {
|
|
var key string
|
|
var err error
|
|
if key, err = cache.MetaNamespaceKeyFunc(obj); err != nil {
|
|
utilruntime.HandleError(err)
|
|
return
|
|
}
|
|
c.workqueue.AddRateLimited(key)
|
|
}
|
|
|
|
func (c *Controller) handleObject(obj interface{}) {
|
|
if _, ok := obj.(metav1.Object); !ok {
|
|
tombstone, ok := obj.(cache.DeletedFinalStateUnknown)
|
|
if !ok {
|
|
utilruntime.HandleError(fmt.Errorf("error decoding object, invalid type"))
|
|
return
|
|
}
|
|
_, ok = tombstone.Obj.(metav1.Object)
|
|
if !ok {
|
|
utilruntime.HandleError(fmt.Errorf("error decoding object tombstone, invalid type"))
|
|
return
|
|
}
|
|
}
|
|
c.enqueue(obj)
|
|
}
|