sync_data.h revision 7dbb3d5cf0c15f500944d211057644d6a2f37371 
1// Copyright 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef SYNC_API_SYNC_DATA_H_
6#define SYNC_API_SYNC_DATA_H_
7
8#include <iosfwd>
9#include <string>
10#include <vector>
11
12#include "base/basictypes.h"
13#include "base/time/time.h"
14#include "sync/base/sync_export.h"
15#include "sync/internal_api/public/base/model_type.h"
16#include "sync/internal_api/public/util/immutable.h"
17
18namespace sync_pb {
19class EntitySpecifics;
20class SyncEntity;
21}  // namespace sync_pb
22
23namespace syncer {
24
25// A light-weight container for immutable sync data. Pass-by-value and storage
26// in STL containers are supported and encouraged if helpful.
27class SYNC_EXPORT SyncData {
28 public:
29  // Creates an empty and invalid SyncData.
30  SyncData();
31   ~SyncData();
32
33   // Default copy and assign welcome.
34
35  // Helper methods for creating SyncData objects for local data.
36  // The sync tag must be a string unique to this datatype and is used as a node
37  // identifier server-side.
38  // For deletes: |datatype| must specify the datatype who node is being
39  // deleted.
40  // For adds/updates: the specifics must be valid and the non-unique title (can
41  // be the same as sync tag) must be specfied.
42  // Note: the non_unique_title is primarily for debug purposes, and will be
43  // overwritten if the datatype is encrypted.
44  static SyncData CreateLocalDelete(
45      const std::string& sync_tag,
46      ModelType datatype);
47  static SyncData CreateLocalData(
48      const std::string& sync_tag,
49      const std::string& non_unique_title,
50      const sync_pb::EntitySpecifics& specifics);
51
52  // Helper method for creating SyncData objects originating from the syncer.
53  static SyncData CreateRemoteData(
54      int64 id,
55      const sync_pb::EntitySpecifics& specifics,
56      const base::Time& last_modified_time);
57
58  // Whether this SyncData holds valid data. The only way to have a SyncData
59  // without valid data is to use the default constructor.
60  bool IsValid() const;
61
62  // Return the datatype we're holding information about. Derived from the sync
63  // datatype specifics.
64  ModelType GetDataType() const;
65
66  // Return the current sync datatype specifics.
67  const sync_pb::EntitySpecifics& GetSpecifics() const;
68
69  // Returns the value of the unique client tag. This is only set for data going
70  // TO the syncer, not coming from.
71  const std::string& GetTag() const;
72
73  // Returns the non unique title (for debugging). Currently only set for data
74  // going TO the syncer, not from.
75  const std::string& GetTitle() const;
76
77  // Returns the last motification time according to the server. This is
78  // only valid if IsLocal() is false, and may be null if the SyncData
79  // represents a deleted item.
80  const base::Time& GetRemoteModifiedTime() const;
81
82  // Should only be called by sync code when IsLocal() is false.
83  int64 GetRemoteId() const;
84
85  // Whether this sync data is for local data or data coming from the syncer.
86  bool IsLocal() const;
87
88  std::string ToString() const;
89
90  // TODO(zea): Query methods for other sync properties: parent, successor, etc.
91
92 private:
93  // Necessary since we forward-declare sync_pb::SyncEntity; see
94  // comments in immutable.h.
95  struct ImmutableSyncEntityTraits {
96    typedef sync_pb::SyncEntity* Wrapper;
97
98    static void InitializeWrapper(Wrapper* wrapper);
99
100    static void DestroyWrapper(Wrapper* wrapper);
101
102    static const sync_pb::SyncEntity& Unwrap(const Wrapper& wrapper);
103
104    static sync_pb::SyncEntity* UnwrapMutable(Wrapper* wrapper);
105
106    static void Swap(sync_pb::SyncEntity* t1, sync_pb::SyncEntity* t2);
107  };
108
109  typedef Immutable<sync_pb::SyncEntity, ImmutableSyncEntityTraits>
110      ImmutableSyncEntity;
111
112  // Clears |entity|.
113  SyncData(int64 id,
114           sync_pb::SyncEntity* entity,
115           const base::Time& remote_modification_time);
116
117  // Whether this SyncData holds valid data.
118  bool is_valid_;
119
120  // Equal to kInvalidId iff this is local.
121  int64 id_;
122
123  // This is only valid if IsLocal() is false, and may be null if the
124  // SyncData represents a deleted item.
125  base::Time remote_modification_time_;
126
127  // The actual shared sync entity being held.
128  ImmutableSyncEntity immutable_entity_;
129};
130
131// gmock printer helper.
132void PrintTo(const SyncData& sync_data, std::ostream* os);
133
134typedef std::vector<SyncData> SyncDataList;
135
136}  // namespace syncer
137
138#endif  // SYNC_API_SYNC_DATA_H_
139