Refactor a bit.

service/rawdatastore/interface.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 rawdatastore
+
+import (
+        "fmt"
+
+        "golang.org/x/net/context"
+)
+
+/// Kinds + Keys
+
+// Key is the equivalent of *datastore.Key from the original SDK, except that
+// it can have multiple implementations. See helper.Key* methods for missing
+// methods like KeyIncomplete (and some new ones like KeyValid).
+type Key interface {
+        Kind() string
+        StringID() string
+        IntID() int64
+        Parent() Key
+        AppID() string
+        Namespace() string
+
+        String() string
+}
+
+// KeyTok is a single token from a multi-part Key.
+type KeyTok struct {
+        Kind     string
+        IntID    int64
+        StringID string
+}
+
+// Cursor wraps datastore.Cursor.
+type Cursor interface {
+        fmt.Stringer
+}
+
+// Query wraps datastore.Query.
+type Query interface {
+        Ancestor(ancestor Key) Query
+        Distinct() Query
+        End(c Cursor) Query
+        EventualConsistency() Query
+        Filter(filterStr string, value interface{}) Query
+        KeysOnly() Query
+        Limit(limit int) Query
+        Offset(offset int) Query
+        Order(fieldName string) Query
+        Project(fieldNames ...string) Query
+        Start(c Cursor) Query
+}
+
+// Iterator wraps datastore.Iterator.
+type Iterator interface {
+        Cursor() (Cursor, error)
+        Next(dst PropertyLoadSaver) (Key, error)
+}
+
+// Interface implements the datastore functionality without any of the fancy
+// reflection stuff. This is so that Filters can avoid doing lots of redundant
+// reflection work. See helper.Datastore for a more user-friendly interface.
+type Interface interface {
+        NewKey(kind, stringID string, intID int64, parent Key) Key
+        DecodeKey(encoded string) (Key, error)
+
+        NewQuery(kind string) Query
+        Count(q Query) (int, error)
+
+        RunInTransaction(f func(c context.Context) error, opts *TransactionOptions) error
+
+        Run(q Query) Iterator
+        GetAll(q Query, dst *[]PropertyMap) ([]Key, error)
+
+        Put(key Key, src PropertyLoadSaver) (Key, error)
+        Get(key Key, dst PropertyLoadSaver) error
+        Delete(key Key) error
+
+        // These allow you to read and write a multiple datastore objects in
+        // a non-atomic batch.
+        DeleteMulti(keys []Key) error
+        GetMulti(keys []Key, dst []PropertyLoadSaver) error
+        PutMulti(keys []Key, src []PropertyLoadSaver) ([]Key, error)
+}