Add 'user friendly' datastore API.

service/rawdatastore/types.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"
-)
-
-// ByteString is a short byte slice (up to 1500 bytes) that can be indexed.
-type ByteString []byte
-
-// GeoPoint represents a location as latitude/longitude in degrees.
-//
-// You probably shouldn't use these, but their inclusion here is so that the
-// RawDatastore can interact (and round-trip) correctly with other datastore API
-// implementations.
-type GeoPoint struct {
-        Lat, Lng float64
-}
-
-// Valid returns whether a GeoPoint is within [-90, 90] latitude and [-180,
-// 180] longitude.
-func (g GeoPoint) Valid() bool {
-        return -90 <= g.Lat && g.Lat <= 90 && -180 <= g.Lng && g.Lng <= 180
-}
-
-// TransactionOptions are the options for running a transaction.
-type TransactionOptions struct {
-        // XG is whether the transaction can cross multiple entity groups. In
-        // comparison, a single group transaction is one where all datastore keys
-        // used have the same root key. Note that cross group transactions do not
-        // have the same behavior as single group transactions. In particular, it
-        // is much more likely to see partially applied transactions in different
-        // entity groups, in global queries.
-        // It is valid to set XG to true even if the transaction is within a
-        // single entity group.
-        XG bool
-        // Attempts controls the number of retries to perform when commits fail
-        // due to a conflicting transaction. If omitted, it defaults to 3.
-        Attempts int
-}
-
-// Toggle is a tri-state boolean (Auto/True/False), which allows structs
-// to control boolean flags for metadata in a non-ambiguous way.
-type Toggle byte
-
-// These are the allowed values for Toggle. Any other values are invalid.
-const (
-        Auto Toggle = iota
-        On
-        Off
-)
-
-func (b Toggle) String() string {
-        switch b {
-        case Auto:
-                return "Auto"
-        case On:
-                return "On"
-        case Off:
-                return "Off"
-        default:
-                return fmt.Sprintf("UNKNOWN_Toggle(%d)", b)
-        }
-}