Refactor a bit.

helper/datastore.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.
-
-// HEAVILY adapted from github.com/golang/appengine/datastore
-
-package helper
-
-import (
-        "reflect"
-
-        "github.com/luci/gae"
-)
-
-// GetPLS resolves o into a gae.DSStructPLS. o must be a pointer to a
-// struct of some sort.
-func GetPLS(o interface{}) gae.DSPropertyLoadSaver {
-        v := reflect.ValueOf(o)
-        if v.Kind() != reflect.Ptr || v.Elem().Kind() != reflect.Struct {
-                return &structPLS{c: &structCodec{problem: gae.ErrDSInvalidEntityType}}
-        }
-        v = v.Elem()
-        t := v.Type()
-
-        structCodecsMutex.RLock()
-        if c, ok := structCodecs[t]; ok {
-                structCodecsMutex.RUnlock()
-                return &structPLS{v, c}
-        }
-        structCodecsMutex.RUnlock()
-
-        structCodecsMutex.Lock()
-        defer structCodecsMutex.Unlock()
-        return &structPLS{v, getStructCodecLocked(t)}
-}