git subrepo clone (merge) https://github.com/kubernetes-incubator/metrics-server.git metrics-server
subrepo:
subdir: "metrics-server"
merged: "92d8412"
upstream:
origin: "https://github.com/kubernetes-incubator/metrics-server.git"
branch: "master"
commit: "92d8412"
git-subrepo:
version: "0.4.0"
origin: "???"
commit: "???"
diff --git a/metrics-server/vendor/k8s.io/apimachinery/pkg/util/cache/lruexpirecache.go b/metrics-server/vendor/k8s.io/apimachinery/pkg/util/cache/lruexpirecache.go
new file mode 100644
index 0000000..f6b307a
--- /dev/null
+++ b/metrics-server/vendor/k8s.io/apimachinery/pkg/util/cache/lruexpirecache.go
@@ -0,0 +1,102 @@
+/*
+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 cache
+
+import (
+ "sync"
+ "time"
+
+ "github.com/hashicorp/golang-lru"
+)
+
+// Clock defines an interface for obtaining the current time
+type Clock interface {
+ Now() time.Time
+}
+
+// realClock implements the Clock interface by calling time.Now()
+type realClock struct{}
+
+func (realClock) Now() time.Time { return time.Now() }
+
+// LRUExpireCache is a cache that ensures the mostly recently accessed keys are returned with
+// a ttl beyond which keys are forcibly expired.
+type LRUExpireCache struct {
+ // clock is used to obtain the current time
+ clock Clock
+
+ cache *lru.Cache
+ lock sync.Mutex
+}
+
+// NewLRUExpireCache creates an expiring cache with the given size
+func NewLRUExpireCache(maxSize int) *LRUExpireCache {
+ return NewLRUExpireCacheWithClock(maxSize, realClock{})
+}
+
+// NewLRUExpireCacheWithClock creates an expiring cache with the given size, using the specified clock to obtain the current time.
+func NewLRUExpireCacheWithClock(maxSize int, clock Clock) *LRUExpireCache {
+ cache, err := lru.New(maxSize)
+ if err != nil {
+ // if called with an invalid size
+ panic(err)
+ }
+ return &LRUExpireCache{clock: clock, cache: cache}
+}
+
+type cacheEntry struct {
+ value interface{}
+ expireTime time.Time
+}
+
+// Add adds the value to the cache at key with the specified maximum duration.
+func (c *LRUExpireCache) Add(key interface{}, value interface{}, ttl time.Duration) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ c.cache.Add(key, &cacheEntry{value, c.clock.Now().Add(ttl)})
+}
+
+// Get returns the value at the specified key from the cache if it exists and is not
+// expired, or returns false.
+func (c *LRUExpireCache) Get(key interface{}) (interface{}, bool) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ e, ok := c.cache.Get(key)
+ if !ok {
+ return nil, false
+ }
+ if c.clock.Now().After(e.(*cacheEntry).expireTime) {
+ c.cache.Remove(key)
+ return nil, false
+ }
+ return e.(*cacheEntry).value, true
+}
+
+// Remove removes the specified key from the cache if it exists
+func (c *LRUExpireCache) Remove(key interface{}) {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ c.cache.Remove(key)
+}
+
+// Keys returns all the keys in the cache, even if they are expired. Subsequent calls to
+// get may return not found. It returns all keys from oldest to newest.
+func (c *LRUExpireCache) Keys() []interface{} {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ return c.cache.Keys()
+}