vendor update for E2E framework

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

vendor/k8s.io/client-go/tools/cache/reflector.go

@@ -0,0 +1,386 @@
+/*
+Copyright 2014 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 cache
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"math/rand"
+	"net"
+	"net/url"
+	"reflect"
+	"strings"
+	"sync"
+	"syscall"
+	"time"
+
+	apierrs "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/api/meta"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/util/clock"
+	"k8s.io/apimachinery/pkg/util/naming"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"k8s.io/apimachinery/pkg/watch"
+	"k8s.io/klog"
+	"k8s.io/utils/trace"
+)
+
+// Reflector watches a specified resource and causes all changes to be reflected in the given store.
+type Reflector struct {
+	// name identifies this reflector. By default it will be a file:line if possible.
+	name string
+	// metrics tracks basic metric information about the reflector
+	metrics *reflectorMetrics
+
+	// The type of object we expect to place in the store.
+	expectedType reflect.Type
+	// The destination to sync up with the watch source
+	store Store
+	// listerWatcher is used to perform lists and watches.
+	listerWatcher ListerWatcher
+	// period controls timing between one watch ending and
+	// the beginning of the next one.
+	period       time.Duration
+	resyncPeriod time.Duration
+	ShouldResync func() bool
+	// clock allows tests to manipulate time
+	clock clock.Clock
+	// lastSyncResourceVersion is the resource version token last
+	// observed when doing a sync with the underlying store
+	// it is thread safe, but not synchronized with the underlying store
+	lastSyncResourceVersion string
+	// lastSyncResourceVersionMutex guards read/write access to lastSyncResourceVersion
+	lastSyncResourceVersionMutex sync.RWMutex
+}
+
+var (
+	// We try to spread the load on apiserver by setting timeouts for
+	// watch requests - it is random in [minWatchTimeout, 2*minWatchTimeout].
+	minWatchTimeout = 5 * time.Minute
+)
+
+// NewNamespaceKeyedIndexerAndReflector creates an Indexer and a Reflector
+// The indexer is configured to key on namespace
+func NewNamespaceKeyedIndexerAndReflector(lw ListerWatcher, expectedType interface{}, resyncPeriod time.Duration) (indexer Indexer, reflector *Reflector) {
+	indexer = NewIndexer(MetaNamespaceKeyFunc, Indexers{"namespace": MetaNamespaceIndexFunc})
+	reflector = NewReflector(lw, expectedType, indexer, resyncPeriod)
+	return indexer, reflector
+}
+
+// NewReflector creates a new Reflector object which will keep the given store up to
+// date with the server's contents for the given resource. Reflector promises to
+// only put things in the store that have the type of expectedType, unless expectedType
+// is nil. If resyncPeriod is non-zero, then lists will be executed after every
+// resyncPeriod, so that you can use reflectors to periodically process everything as
+// well as incrementally processing the things that change.
+func NewReflector(lw ListerWatcher, expectedType interface{}, store Store, resyncPeriod time.Duration) *Reflector {
+	return NewNamedReflector(naming.GetNameFromCallsite(internalPackages...), lw, expectedType, store, resyncPeriod)
+}
+
+// NewNamedReflector same as NewReflector, but with a specified name for logging
+func NewNamedReflector(name string, lw ListerWatcher, expectedType interface{}, store Store, resyncPeriod time.Duration) *Reflector {
+	r := &Reflector{
+		name:          name,
+		listerWatcher: lw,
+		store:         store,
+		expectedType:  reflect.TypeOf(expectedType),
+		period:        time.Second,
+		resyncPeriod:  resyncPeriod,
+		clock:         &clock.RealClock{},
+	}
+	return r
+}
+
+func makeValidPrometheusMetricLabel(in string) string {
+	// this isn't perfect, but it removes our common characters
+	return strings.NewReplacer("/", "_", ".", "_", "-", "_", ":", "_").Replace(in)
+}
+
+// internalPackages are packages that ignored when creating a default reflector name. These packages are in the common
+// call chains to NewReflector, so they'd be low entropy names for reflectors
+var internalPackages = []string{"client-go/tools/cache/"}
+
+// Run starts a watch and handles watch events. Will restart the watch if it is closed.
+// Run will exit when stopCh is closed.
+func (r *Reflector) Run(stopCh <-chan struct{}) {
+	klog.V(3).Infof("Starting reflector %v (%s) from %s", r.expectedType, r.resyncPeriod, r.name)
+	wait.Until(func() {
+		if err := r.ListAndWatch(stopCh); err != nil {
+			utilruntime.HandleError(err)
+		}
+	}, r.period, stopCh)
+}
+
+var (
+	// nothing will ever be sent down this channel
+	neverExitWatch <-chan time.Time = make(chan time.Time)
+
+	// Used to indicate that watching stopped so that a resync could happen.
+	errorResyncRequested = errors.New("resync channel fired")
+
+	// Used to indicate that watching stopped because of a signal from the stop
+	// channel passed in from a client of the reflector.
+	errorStopRequested = errors.New("Stop requested")
+)
+
+// resyncChan returns a channel which will receive something when a resync is
+// required, and a cleanup function.
+func (r *Reflector) resyncChan() (<-chan time.Time, func() bool) {
+	if r.resyncPeriod == 0 {
+		return neverExitWatch, func() bool { return false }
+	}
+	// The cleanup function is required: imagine the scenario where watches
+	// always fail so we end up listing frequently. Then, if we don't
+	// manually stop the timer, we could end up with many timers active
+	// concurrently.
+	t := r.clock.NewTimer(r.resyncPeriod)
+	return t.C(), t.Stop
+}
+
+// ListAndWatch first lists all items and get the resource version at the moment of call,
+// and then use the resource version to watch.
+// It returns error if ListAndWatch didn't even try to initialize watch.
+func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
+	klog.V(3).Infof("Listing and watching %v from %s", r.expectedType, r.name)
+	var resourceVersion string
+
+	// Explicitly set "0" as resource version - it's fine for the List()
+	// to be served from cache and potentially be delayed relative to
+	// etcd contents. Reflector framework will catch up via Watch() eventually.
+	options := metav1.ListOptions{ResourceVersion: "0"}
+
+	if err := func() error {
+		initTrace := trace.New("Reflector " + r.name + " ListAndWatch")
+		defer initTrace.LogIfLong(10 * time.Second)
+		var list runtime.Object
+		var err error
+		listCh := make(chan struct{}, 1)
+		panicCh := make(chan interface{}, 1)
+		go func() {
+			defer func() {
+				if r := recover(); r != nil {
+					panicCh <- r
+				}
+			}()
+			list, err = r.listerWatcher.List(options)
+			close(listCh)
+		}()
+		select {
+		case <-stopCh:
+			return nil
+		case r := <-panicCh:
+			panic(r)
+		case <-listCh:
+		}
+		if err != nil {
+			return fmt.Errorf("%s: Failed to list %v: %v", r.name, r.expectedType, err)
+		}
+		initTrace.Step("Objects listed")
+		listMetaInterface, err := meta.ListAccessor(list)
+		if err != nil {
+			return fmt.Errorf("%s: Unable to understand list result %#v: %v", r.name, list, err)
+		}
+		resourceVersion = listMetaInterface.GetResourceVersion()
+		initTrace.Step("Resource version extracted")
+		items, err := meta.ExtractList(list)
+		if err != nil {
+			return fmt.Errorf("%s: Unable to understand list result %#v (%v)", r.name, list, err)
+		}
+		initTrace.Step("Objects extracted")
+		if err := r.syncWith(items, resourceVersion); err != nil {
+			return fmt.Errorf("%s: Unable to sync list result: %v", r.name, err)
+		}
+		initTrace.Step("SyncWith done")
+		r.setLastSyncResourceVersion(resourceVersion)
+		initTrace.Step("Resource version updated")
+		return nil
+	}(); err != nil {
+		return err
+	}
+
+	resyncerrc := make(chan error, 1)
+	cancelCh := make(chan struct{})
+	defer close(cancelCh)
+	go func() {
+		resyncCh, cleanup := r.resyncChan()
+		defer func() {
+			cleanup() // Call the last one written into cleanup
+		}()
+		for {
+			select {
+			case <-resyncCh:
+			case <-stopCh:
+				return
+			case <-cancelCh:
+				return
+			}
+			if r.ShouldResync == nil || r.ShouldResync() {
+				klog.V(4).Infof("%s: forcing resync", r.name)
+				if err := r.store.Resync(); err != nil {
+					resyncerrc <- err
+					return
+				}
+			}
+			cleanup()
+			resyncCh, cleanup = r.resyncChan()
+		}
+	}()
+
+	for {
+		// give the stopCh a chance to stop the loop, even in case of continue statements further down on errors
+		select {
+		case <-stopCh:
+			return nil
+		default:
+		}
+
+		timeoutSeconds := int64(minWatchTimeout.Seconds() * (rand.Float64() + 1.0))
+		options = metav1.ListOptions{
+			ResourceVersion: resourceVersion,
+			// We want to avoid situations of hanging watchers. Stop any wachers that do not
+			// receive any events within the timeout window.
+			TimeoutSeconds: &timeoutSeconds,
+		}
+
+		w, err := r.listerWatcher.Watch(options)
+		if err != nil {
+			switch err {
+			case io.EOF:
+				// watch closed normally
+			case io.ErrUnexpectedEOF:
+				klog.V(1).Infof("%s: Watch for %v closed with unexpected EOF: %v", r.name, r.expectedType, err)
+			default:
+				utilruntime.HandleError(fmt.Errorf("%s: Failed to watch %v: %v", r.name, r.expectedType, err))
+			}
+			// If this is "connection refused" error, it means that most likely apiserver is not responsive.
+			// It doesn't make sense to re-list all objects because most likely we will be able to restart
+			// watch where we ended.
+			// If that's the case wait and resend watch request.
+			if urlError, ok := err.(*url.Error); ok {
+				if opError, ok := urlError.Err.(*net.OpError); ok {
+					if errno, ok := opError.Err.(syscall.Errno); ok && errno == syscall.ECONNREFUSED {
+						time.Sleep(time.Second)
+						continue
+					}
+				}
+			}
+			return nil
+		}
+
+		if err := r.watchHandler(w, &resourceVersion, resyncerrc, stopCh); err != nil {
+			if err != errorStopRequested {
+				klog.Warningf("%s: watch of %v ended with: %v", r.name, r.expectedType, err)
+			}
+			return nil
+		}
+	}
+}
+
+// syncWith replaces the store's items with the given list.
+func (r *Reflector) syncWith(items []runtime.Object, resourceVersion string) error {
+	found := make([]interface{}, 0, len(items))
+	for _, item := range items {
+		found = append(found, item)
+	}
+	return r.store.Replace(found, resourceVersion)
+}
+
+// watchHandler watches w and keeps *resourceVersion up to date.
+func (r *Reflector) watchHandler(w watch.Interface, resourceVersion *string, errc chan error, stopCh <-chan struct{}) error {
+	start := r.clock.Now()
+	eventCount := 0
+
+	// Stopping the watcher should be idempotent and if we return from this function there's no way
+	// we're coming back in with the same watch interface.
+	defer w.Stop()
+
+loop:
+	for {
+		select {
+		case <-stopCh:
+			return errorStopRequested
+		case err := <-errc:
+			return err
+		case event, ok := <-w.ResultChan():
+			if !ok {
+				break loop
+			}
+			if event.Type == watch.Error {
+				return apierrs.FromObject(event.Object)
+			}
+			if e, a := r.expectedType, reflect.TypeOf(event.Object); e != nil && e != a {
+				utilruntime.HandleError(fmt.Errorf("%s: expected type %v, but watch event object had type %v", r.name, e, a))
+				continue
+			}
+			meta, err := meta.Accessor(event.Object)
+			if err != nil {
+				utilruntime.HandleError(fmt.Errorf("%s: unable to understand watch event %#v", r.name, event))
+				continue
+			}
+			newResourceVersion := meta.GetResourceVersion()
+			switch event.Type {
+			case watch.Added:
+				err := r.store.Add(event.Object)
+				if err != nil {
+					utilruntime.HandleError(fmt.Errorf("%s: unable to add watch event object (%#v) to store: %v", r.name, event.Object, err))
+				}
+			case watch.Modified:
+				err := r.store.Update(event.Object)
+				if err != nil {
+					utilruntime.HandleError(fmt.Errorf("%s: unable to update watch event object (%#v) to store: %v", r.name, event.Object, err))
+				}
+			case watch.Deleted:
+				// TODO: Will any consumers need access to the "last known
+				// state", which is passed in event.Object? If so, may need
+				// to change this.
+				err := r.store.Delete(event.Object)
+				if err != nil {
+					utilruntime.HandleError(fmt.Errorf("%s: unable to delete watch event object (%#v) from store: %v", r.name, event.Object, err))
+				}
+			default:
+				utilruntime.HandleError(fmt.Errorf("%s: unable to understand watch event %#v", r.name, event))
+			}
+			*resourceVersion = newResourceVersion
+			r.setLastSyncResourceVersion(newResourceVersion)
+			eventCount++
+		}
+	}
+
+	watchDuration := r.clock.Now().Sub(start)
+	if watchDuration < 1*time.Second && eventCount == 0 {
+		return fmt.Errorf("very short watch: %s: Unexpected watch close - watch lasted less than a second and no items received", r.name)
+	}
+	klog.V(4).Infof("%s: Watch close - %v total %v items received", r.name, r.expectedType, eventCount)
+	return nil
+}
+
+// LastSyncResourceVersion is the resource version observed when last sync with the underlying store
+// The value returned is not synchronized with access to the underlying store and is not thread-safe
+func (r *Reflector) LastSyncResourceVersion() string {
+	r.lastSyncResourceVersionMutex.RLock()
+	defer r.lastSyncResourceVersionMutex.RUnlock()
+	return r.lastSyncResourceVersion
+}
+
+func (r *Reflector) setLastSyncResourceVersion(v string) {
+	r.lastSyncResourceVersionMutex.Lock()
+	defer r.lastSyncResourceVersionMutex.Unlock()
+	r.lastSyncResourceVersion = v
+}