Refactor a bit.

service/memcache/types.go

Index: service/memcache/types.go
diff --git a/service/memcache/types.go b/service/memcache/types.go
new file mode 100644
index 0000000000000000000000000000000000000000..1bc49d8cde1cc123d664337ac0f6e317059eb819
--- /dev/null
+++ b/service/memcache/types.go
@@ -0,0 +1,42 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package memcache
+
+import (
+	"time"
+)
+
+// Statistics represents a set of statistics about the memcache cache.  This
+// may include items that have expired but have not yet been removed from the
+// cache.
+type Statistics struct {
+	Hits     uint64 // Counter of cache hits
+	Misses   uint64 // Counter of cache misses
+	ByteHits uint64 // Counter of bytes transferred for gets
+
+	Items uint64 // Items currently in the cache
+	Bytes uint64 // Size of all items currently in the cache
+
+	Oldest int64 // Age of access of the oldest item, in seconds
+}
+
+// Item is a wrapper around *memcache.Item. Note that the Set* methods all
+// return the original Item (e.g. they mutate the original), due to
+// implementation constraints. They return the original item to allow easy
+// chaining, e.g.:
+//   itm := memcache.Get(c).NewItem("foo").SetValue([]byte("stuff"))
+type Item interface {
+	Key() string
+	Value() []byte
+	Object() interface{}
+	Flags() uint32
+	Expiration() time.Duration
+
+	SetKey(string) Item
+	SetValue([]byte) Item
+	SetObject(interface{}) Item
+	SetFlags(uint32) Item
+	SetExpiration(time.Duration) Item
+}