add mutation cache filter

staging/src/k8s.io/apiserver/Godeps/Godeps.json

@@ -435,6 +435,14 @@
 			"Rev": "84398b94e188ee336f307779b57b3aa91af7063c"
 		},
 		{
+			"ImportPath": "github.com/hashicorp/golang-lru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
+			"ImportPath": "github.com/hashicorp/golang-lru/simplelru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
 			"ImportPath": "github.com/howeyc/gopass",
 			"Rev": "3ca23474a7c7203e0a0a070fd33508f6efdb9b3d"
 		},

staging/src/k8s.io/client-go/Godeps/Godeps.json

 {
 	"ImportPath": "k8s.io/client-go",
-	"GoVersion": "go1.7",
+	"GoVersion": "go1.8",
 	"GodepVersion": "v79",
 	"Packages": [
 		"./..."
@@ -139,6 +139,14 @@
 			"Rev": "44d81051d367757e1c7c6a5a86423ece9afcf63c"
 		},
 		{
+			"ImportPath": "github.com/hashicorp/golang-lru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
+			"ImportPath": "github.com/hashicorp/golang-lru/simplelru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
 			"ImportPath": "github.com/howeyc/gopass",
 			"Rev": "3ca23474a7c7203e0a0a070fd33508f6efdb9b3d"
 		},

staging/src/k8s.io/client-go/tools/cache/index.go

@@ -28,6 +28,8 @@ type Indexer interface {
 	Store
 	// Retrieve list of objects that match on the named indexing function
 	Index(indexName string, obj interface{}) ([]interface{}, error)
+	// IndexKeys returns the set of keys that match on the named indexing function.
+	IndexKeys(indexName, indexKey string) ([]string, error)
 	// ListIndexFuncValues returns the list of generated values of an Index func
 	ListIndexFuncValues(indexName string) []string
 	// ByIndex lists object that match on the named indexing function with the exact key

staging/src/k8s.io/client-go/tools/cache/mutation_cache.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 cache
+
+import (
+	"fmt"
+	"strconv"
+	"sync"
+
+	lru "github.com/hashicorp/golang-lru"
+
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+)
+
+// MutationCache is able to take the result of update operations and stores them in an LRU
+// that can be used to provide a more current view of a requested object.  It requires interpretting
+// resourceVersions for comparisons.
+// Implementations must be thread-safe.
+// TODO find a way to layer this into an informer/lister
+type MutationCache interface {
+	GetByKey(key string) (interface{}, bool, error)
+	ByIndex(indexName, indexKey string) ([]interface{}, error)
+	Mutation(interface{})
+}
+
+type ResourceVersionComparator interface {
+	CompareResourceVersion(lhs, rhs runtime.Object) int
+}
+
+// NewIntegerResourceVersionMutationCache returns a MutationCache that understands how to
+// deal with objects that have a resource version that:
+//
+//   - is an integer
+//   - increases when updated
+//   - is comparable across the same resource in a namespace
+//
+// Most backends will have these semantics. Indexer may be nil.
+func NewIntegerResourceVersionMutationCache(backingCache Store, indexer Indexer) MutationCache {
+	lru, err := lru.New(100)
+	if err != nil {
+		// errors only happen on invalid sizes, this would be programmer error
+		panic(err)
+	}
+
+	return &mutationCache{
+		backingCache:  backingCache,
+		indexer:       indexer,
+		mutationCache: lru,
+		comparator:    etcdObjectVersioner{},
+	}
+}
+
+// mutationCache doesn't guarantee that it returns values added via Mutation since they can page out and
+// since you can't distinguish between, "didn't observe create" and "was deleted after create",
+// if the key is missing from the backing cache, we always return it as missing
+type mutationCache struct {
+	lock          sync.Mutex
+	backingCache  Store
+	indexer       Indexer
+	mutationCache *lru.Cache
+
+	comparator ResourceVersionComparator
+}
+
+// GetByKey is never guaranteed to return back the value set in Mutation.  It could be paged out, it could
+// be older than another copy, the backingCache may be more recent or, you might have written twice into the same key.
+// You get a value that was valid at some snapshot of time and will always return the newer of backingCache and mutationCache.
+func (c *mutationCache) GetByKey(key string) (interface{}, bool, error) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	obj, exists, err := c.backingCache.GetByKey(key)
+	if err != nil {
+		return nil, false, err
+	}
+	if !exists {
+		// we can't distinguish between, "didn't observe create" and "was deleted after create", so
+		// if the key is missing, we always return it as missing
+		return nil, false, nil
+	}
+	objRuntime, ok := obj.(runtime.Object)
+	if !ok {
+		return obj, true, nil
+	}
+	return c.newerObject(key, objRuntime), true, nil
+}
+
+// ByIndex returns the newer objects that match the provided index and indexer key.
+// Will return an error if no indexer was provided.
+func (c *mutationCache) ByIndex(name string, indexKey string) ([]interface{}, error) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+	if c.indexer == nil {
+		return nil, fmt.Errorf("no indexer has been provided to the mutation cache")
+	}
+	keys, err := c.indexer.IndexKeys(name, indexKey)
+	if err != nil {
+		return nil, err
+	}
+	var items []interface{}
+	for _, key := range keys {
+		obj, exists, err := c.indexer.GetByKey(key)
+		if err != nil {
+			return nil, err
+		}
+		if !exists {
+			continue
+		}
+		if objRuntime, ok := obj.(runtime.Object); ok {
+			items = append(items, c.newerObject(key, objRuntime))
+		} else {
+			items = append(items, obj)
+		}
+	}
+	return items, nil
+}
+
+// newerObject checks the mutation cache for a newer object and returns one if found. If the
+// mutated object is older than the backing object, it is removed from the  Must be
+// called while the lock is held.
+func (c *mutationCache) newerObject(key string, backing runtime.Object) runtime.Object {
+	mutatedObj, exists := c.mutationCache.Get(key)
+	if !exists {
+		return backing
+	}
+	mutatedObjRuntime, ok := mutatedObj.(runtime.Object)
+	if !ok {
+		return backing
+	}
+	if c.comparator.CompareResourceVersion(backing, mutatedObjRuntime) >= 0 {
+		c.mutationCache.Remove(key)
+		return backing
+	}
+	return mutatedObjRuntime
+}
+
+// Mutation adds a change to the cache that can be returned in GetByKey if it is newer than the backingCache
+// copy.  If you call Mutation twice with the same object on different threads, one will win, but its not defined
+// which one.  This doesn't affect correctness, since the GetByKey guaranteed of "later of these two caches" is
+// preserved, but you may not get the version of the object you want.  The object you get is only guaranteed to
+// "one that was valid at some point in time", not "the one that I want".
+func (c *mutationCache) Mutation(obj interface{}) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	key, err := DeletionHandlingMetaNamespaceKeyFunc(obj)
+	if err != nil {
+		// this is a "nice to have", so failures shouldn't do anything weird
+		utilruntime.HandleError(err)
+		return
+	}
+
+	if objRuntime, ok := obj.(runtime.Object); ok {
+		if mutatedObj, exists := c.mutationCache.Get(key); exists {
+			if mutatedObjRuntime, ok := mutatedObj.(runtime.Object); ok {
+				if c.comparator.CompareResourceVersion(objRuntime, mutatedObjRuntime) < 0 {
+					return
+				}
+			}
+		}
+	}
+	c.mutationCache.Add(key, obj)
+}
+
+// etcdObjectVersioner implements versioning and extracting etcd node information
+// for objects that have an embedded ObjectMeta or ListMeta field.
+type etcdObjectVersioner struct{}
+
+// ObjectResourceVersion implements Versioner
+func (a etcdObjectVersioner) ObjectResourceVersion(obj runtime.Object) (uint64, error) {
+	accessor, err := meta.Accessor(obj)
+	if err != nil {
+		return 0, err
+	}
+	version := accessor.GetResourceVersion()
+	if len(version) == 0 {
+		return 0, nil
+	}
+	return strconv.ParseUint(version, 10, 64)
+}
+
+// CompareResourceVersion compares etcd resource versions.  Outside this API they are all strings,
+// but etcd resource versions are special, they're actually ints, so we can easily compare them.
+func (a etcdObjectVersioner) CompareResourceVersion(lhs, rhs runtime.Object) int {
+	lhsVersion, err := a.ObjectResourceVersion(lhs)
+	if err != nil {
+		// coder error
+		panic(err)
+	}
+	rhsVersion, err := a.ObjectResourceVersion(rhs)
+	if err != nil {
+		// coder error
+		panic(err)
+	}
+
+	if lhsVersion == rhsVersion {
+		return 0
+	}
+	if lhsVersion < rhsVersion {
+		return -1
+	}
+
+	return 1
+}

staging/src/k8s.io/client-go/tools/cache/store.go

@@ -172,6 +172,10 @@ func (c *cache) Index(indexName string, obj interface{}) ([]interface{}, error)
 	return c.cacheStorage.Index(indexName, obj)
 }
 
+func (c *cache) IndexKeys(indexName, indexKey string) ([]string, error) {
+	return c.cacheStorage.IndexKeys(indexName, indexKey)
+}
+
 // ListIndexFuncValues returns the list of generated values of an Index func
 func (c *cache) ListIndexFuncValues(indexName string) []string {
 	return c.cacheStorage.ListIndexFuncValues(indexName)

staging/src/k8s.io/client-go/tools/cache/thread_safe_store.go

@@ -43,6 +43,7 @@ type ThreadSafeStore interface {
 	ListKeys() []string
 	Replace(map[string]interface{}, string)
 	Index(indexName string, obj interface{}) ([]interface{}, error)
+	IndexKeys(indexName, indexKey string) ([]string, error)
 	ListIndexFuncValues(name string) []string
 	ByIndex(indexName, indexKey string) ([]interface{}, error)
 	GetIndexers() Indexers
@@ -184,6 +185,23 @@ func (c *threadSafeMap) ByIndex(indexName, indexKey string) ([]interface{}, erro
 	return list, nil
 }
 
+// IndexKeys returns a list of keys that match on the index function.
+// IndexKeys is thread-safe so long as you treat all items as immutable.
+func (c *threadSafeMap) IndexKeys(indexName, indexKey string) ([]string, error) {
+	c.lock.RLock()
+	defer c.lock.RUnlock()
+
+	indexFunc := c.indexers[indexName]
+	if indexFunc == nil {
+		return nil, fmt.Errorf("Index with name %s does not exist", indexName)
+	}
+
+	index := c.indices[indexName]
+
+	set := index[indexKey]
+	return set.List(), nil
+}
+
 func (c *threadSafeMap) ListIndexFuncValues(indexName string) []string {
 	c.lock.RLock()
 	defer c.lock.RUnlock()

staging/src/k8s.io/kube-aggregator/Godeps/Godeps.json

@@ -191,6 +191,14 @@
 			"Rev": "84398b94e188ee336f307779b57b3aa91af7063c"
 		},
 		{
+			"ImportPath": "github.com/hashicorp/golang-lru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
+			"ImportPath": "github.com/hashicorp/golang-lru/simplelru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
 			"ImportPath": "github.com/howeyc/gopass",
 			"Rev": "3ca23474a7c7203e0a0a070fd33508f6efdb9b3d"
 		},

staging/src/k8s.io/kube-apiextensions-server/Godeps/Godeps.json

@@ -183,6 +183,14 @@
 			"Rev": "84398b94e188ee336f307779b57b3aa91af7063c"
 		},
 		{
+			"ImportPath": "github.com/hashicorp/golang-lru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
+			"ImportPath": "github.com/hashicorp/golang-lru/simplelru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
 			"ImportPath": "github.com/howeyc/gopass",
 			"Rev": "3ca23474a7c7203e0a0a070fd33508f6efdb9b3d"
 		},

staging/src/k8s.io/sample-apiserver/Godeps/Godeps.json

@@ -175,6 +175,14 @@
 			"Rev": "84398b94e188ee336f307779b57b3aa91af7063c"
 		},
 		{
+			"ImportPath": "github.com/hashicorp/golang-lru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
+			"ImportPath": "github.com/hashicorp/golang-lru/simplelru",
+			"Rev": "a0d98a5f288019575c6d1f4bb1573fef2d1fcdc4"
+		},
+		{
 			"ImportPath": "github.com/howeyc/gopass",
 			"Rev": "3ca23474a7c7203e0a0a070fd33508f6efdb9b3d"
 		},