Refactor a bit.

impl/prod/memcache.go

 // 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 prod
 
 import (
         "time"
 
         "github.com/luci/gae"
+        mc "github.com/luci/gae/service/memcache"
         "golang.org/x/net/context"
         "google.golang.org/appengine/memcache"
 )
 
 // useMC adds a gae.Memcache implementation to context, accessible
 // by gae.GetMC(c)
 func useMC(c context.Context) context.Context {
-        return gae.SetMCFactory(c, func(ci context.Context) gae.Memcache {
+        return mc.SetFactory(c, func(ci context.Context) mc.Interface {
                 return mcImpl{ci}
         })
 }
 
 type mcImpl struct{ context.Context }
 
 type mcItem struct {
         i *memcache.Item
 }
 
-var _ gae.MCItem = mcItem{}
+var _ mc.Item = mcItem{}
 
 func (i mcItem) Key() string               { return i.i.Key }
 func (i mcItem) Value() []byte             { return i.i.Value }
 func (i mcItem) Object() interface{}       { return i.i.Object }
 func (i mcItem) Flags() uint32             { return i.i.Flags }
 func (i mcItem) Expiration() time.Duration { return i.i.Expiration }
 
-func (i mcItem) SetKey(k string) gae.MCItem {
+func (i mcItem) SetKey(k string) mc.Item {
         i.i.Key = k
         return i
 }
-func (i mcItem) SetValue(v []byte) gae.MCItem {
+func (i mcItem) SetValue(v []byte) mc.Item {
         i.i.Value = v
         return i
 }
-func (i mcItem) SetObject(o interface{}) gae.MCItem {
+func (i mcItem) SetObject(o interface{}) mc.Item {
         i.i.Object = o
         return i
 }
-func (i mcItem) SetFlags(f uint32) gae.MCItem {
+func (i mcItem) SetFlags(f uint32) mc.Item {
         i.i.Flags = f
         return i
 }
-func (i mcItem) SetExpiration(d time.Duration) gae.MCItem {
+func (i mcItem) SetExpiration(d time.Duration) mc.Item {
         i.i.Expiration = d
         return i
 }
 
-// mcR2FErr (MC real-to-fake w/ error) converts a *memcache.Item to a gae.MCItem,
+// mcR2FErr (MC real-to-fake w/ error) converts a *memcache.Item to a mc.Item,
 // and passes along an error.
-func mcR2FErr(i *memcache.Item, err error) (gae.MCItem, error) {
+func mcR2FErr(i *memcache.Item, err error) (mc.Item, error) {
         if err != nil {
                 return nil, err
         }
         return mcItem{i}, nil
 }
 
-// mcF2R (MC fake-to-real) converts a gae.MCItem. i must originate from inside
+// mcF2R (MC fake-to-real) converts a mc.Item. i must originate from inside
 // this package for this function to work (see the panic message for why).
-func mcF2R(i gae.MCItem) *memcache.Item {
+func mcF2R(i mc.Item) *memcache.Item {
         if mci, ok := i.(mcItem); ok {
                 return mci.i
         }
         panic(
-                "you may not use other gae.MCItem implementations with this " +
+                "you may not use other mc.Item implementations with this " +
                         "implementation of gae.Memcache, since it will cause all CompareAndSwap " +
                         "operations to fail. Please use the NewItem api instead.")
 }
 
-// mcMF2R (MC multi-fake-to-real) converts a slice of gae.MCItem to a slice of
+// mcMF2R (MC multi-fake-to-real) converts a slice of mc.Item to a slice of
 // *memcache.Item.
-func mcMF2R(items []gae.MCItem) []*memcache.Item {
+func mcMF2R(items []mc.Item) []*memcache.Item {
         realItems := make([]*memcache.Item, len(items))
         for i, itm := range items {
                 realItems[i] = mcF2R(itm)
         }
         return realItems
 }
 
-func (m mcImpl) NewItem(key string) gae.MCItem {
+func (m mcImpl) NewItem(key string) mc.Item {
         return mcItem{&memcache.Item{Key: key}}
 }
 
 //////// MCSingleReadWriter
-func (m mcImpl) Add(item gae.MCItem) error {
+func (m mcImpl) Add(item mc.Item) error {
         return memcache.Add(m.Context, mcF2R(item))
 }
-func (m mcImpl) Set(item gae.MCItem) error {
+func (m mcImpl) Set(item mc.Item) error {
         return memcache.Set(m.Context, mcF2R(item))
 }
 func (m mcImpl) Delete(key string) error {
         return memcache.Delete(m.Context, key)
 }
-func (m mcImpl) Get(key string) (gae.MCItem, error) {
+func (m mcImpl) Get(key string) (mc.Item, error) {
         return mcR2FErr(memcache.Get(m.Context, key))
 }
-func (m mcImpl) CompareAndSwap(item gae.MCItem) error {
+func (m mcImpl) CompareAndSwap(item mc.Item) error {
         return memcache.CompareAndSwap(m.Context, mcF2R(item))
 }
 
 //////// MCMultiReadWriter
 func (m mcImpl) DeleteMulti(keys []string) error {
         return gae.FixError(memcache.DeleteMulti(m.Context, keys))
 }
-func (m mcImpl) AddMulti(items []gae.MCItem) error {
+func (m mcImpl) AddMulti(items []mc.Item) error {
         return gae.FixError(memcache.AddMulti(m.Context, mcMF2R(items)))
 }
-func (m mcImpl) SetMulti(items []gae.MCItem) error {
+func (m mcImpl) SetMulti(items []mc.Item) error {
         return gae.FixError(memcache.SetMulti(m.Context, mcMF2R(items)))
 }
-func (m mcImpl) GetMulti(keys []string) (map[string]gae.MCItem, error) {
+func (m mcImpl) GetMulti(keys []string) (map[string]mc.Item, error) {
         realItems, err := memcache.GetMulti(m.Context, keys)
         if err != nil {
                 return nil, gae.FixError(err)
         }
-        items := make(map[string]gae.MCItem, len(realItems))
+        items := make(map[string]mc.Item, len(realItems))
         for k, itm := range realItems {
                 items[k] = mcItem{itm}
         }
         return items, err
 }
-func (m mcImpl) CompareAndSwapMulti(items []gae.MCItem) error {
+func (m mcImpl) CompareAndSwapMulti(items []mc.Item) error {
         return gae.FixError(memcache.CompareAndSwapMulti(m.Context, mcMF2R(items)))
 }
 
 //////// MCIncrementer
 func (m mcImpl) Increment(key string, delta int64, initialValue uint64) (uint64, error) {
         return memcache.Increment(m.Context, key, delta, initialValue)
 }
 func (m mcImpl) IncrementExisting(key string, delta int64) (uint64, error) {
         return memcache.IncrementExisting(m.Context, key, delta)
 }
 
 //////// MCFlusher
 func (m mcImpl) Flush() error {
         return memcache.Flush(m.Context)
 }
 
 //////// MCStatter
-func (m mcImpl) Stats() (*gae.MCStatistics, error) {
+func (m mcImpl) Stats() (*mc.Statistics, error) {
         stats, err := memcache.Stats(m.Context)
         if err != nil {
                 return nil, err
         }
-        return (*gae.MCStatistics)(stats), nil
+        return (*mc.Statistics)(stats), nil
 }