1 // Copyright (c) 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_ENGINE_SYNCER_H_ 6 #define SYNC_ENGINE_SYNCER_H_ 7 8 #include <utility> 9 #include <vector> 10 11 #include "base/basictypes.h" 12 #include "base/callback.h" 13 #include "base/gtest_prod_util.h" 14 #include "base/synchronization/lock.h" 15 #include "sync/base/sync_export.h" 16 #include "sync/engine/conflict_resolver.h" 17 #include "sync/engine/syncer_types.h" 18 #include "sync/internal_api/public/base/model_type.h" 19 #include "sync/sessions/sync_session.h" 20 #include "sync/util/extensions_activity.h" 21 22 namespace syncer { 23 24 class CancelationSignal; 25 class CommitProcessor; 26 class GetUpdatesProcessor; 27 28 // A Syncer provides a control interface for driving the sync cycle. These 29 // cycles consist of downloading updates, parsing the response (aka. process 30 // updates), applying updates while resolving conflicts, and committing local 31 // changes. Some of these steps may be skipped if they're deemed to be 32 // unnecessary. 33 // 34 // A Syncer instance expects to run on a dedicated thread. Calls to SyncShare() 35 // may take an unbounded amount of time because it may block on network I/O, on 36 // lock contention, or on tasks posted to other threads. 37 class SYNC_EXPORT_PRIVATE Syncer { 38 public: 39 typedef std::vector<int64> UnsyncedMetaHandles; 40 41 Syncer(CancelationSignal* cancelation_signal); 42 virtual ~Syncer(); 43 44 bool ExitRequested(); 45 46 // Fetches and applies updates, resolves conflicts and commits local changes 47 // for |request_types| as necessary until client and server states are in 48 // sync. The |nudge_tracker| contains state that describes why the client is 49 // out of sync and what must be done to bring it back into sync. 50 virtual bool NormalSyncShare(ModelTypeSet request_types, 51 const sessions::NudgeTracker& nudge_tracker, 52 sessions::SyncSession* session); 53 54 // Performs an initial download for the |request_types|. It is assumed that 55 // the specified types have no local state, and that their associated change 56 // processors are in "passive" mode, so none of the downloaded updates will be 57 // applied to the model. The |source| is sent up to the server for debug 58 // purposes. It describes the reson for performing this initial download. 59 virtual bool ConfigureSyncShare( 60 ModelTypeSet request_types, 61 sync_pb::GetUpdatesCallerInfo::GetUpdatesSource source, 62 sessions::SyncSession* session); 63 64 // Requests to download updates for the |request_types|. For a well-behaved 65 // client with a working connection to the invalidations server, this should 66 // be unnecessary. It may be invoked periodically to try to keep the client 67 // in sync despite bugs or transient failures. 68 virtual bool PollSyncShare(ModelTypeSet request_types, 69 sessions::SyncSession* session); 70 71 private: 72 bool DownloadAndApplyUpdates( 73 ModelTypeSet request_types, 74 sessions::SyncSession* session, 75 GetUpdatesProcessor* get_updates_processor, 76 bool create_mobile_bookmarks_folder); 77 78 // This function will commit batches of unsynced items to the server until the 79 // number of unsynced and ready to commit items reaches zero or an error is 80 // encountered. A request to exit early will be treated as an error and will 81 // abort any blocking operations. 82 SyncerError BuildAndPostCommits( 83 ModelTypeSet request_types, 84 sessions::SyncSession* session, 85 CommitProcessor* commit_processor); 86 87 void HandleCycleBegin(sessions::SyncSession* session); 88 bool HandleCycleEnd( 89 sessions::SyncSession* session, 90 sync_pb::GetUpdatesCallerInfo::GetUpdatesSource source); 91 92 syncer::CancelationSignal* const cancelation_signal_; 93 94 friend class SyncerTest; 95 FRIEND_TEST_ALL_PREFIXES(SyncerTest, NameClashWithResolver); 96 FRIEND_TEST_ALL_PREFIXES(SyncerTest, IllegalAndLegalUpdates); 97 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingAndNewParent); 98 FRIEND_TEST_ALL_PREFIXES(SyncerTest, 99 TestCommitListOrderingAndNewParentAndChild); 100 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingCounterexample); 101 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingWithNesting); 102 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestCommitListOrderingWithNewItems); 103 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestGetUnsyncedAndSimpleCommit); 104 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestPurgeWhileUnsynced); 105 FRIEND_TEST_ALL_PREFIXES(SyncerTest, TestPurgeWhileUnapplied); 106 FRIEND_TEST_ALL_PREFIXES(SyncerTest, UnappliedUpdateDuringCommit); 107 FRIEND_TEST_ALL_PREFIXES(SyncerTest, DeletingEntryInFolder); 108 FRIEND_TEST_ALL_PREFIXES(SyncerTest, 109 LongChangelistCreatesFakeOrphanedEntries); 110 FRIEND_TEST_ALL_PREFIXES(SyncerTest, QuicklyMergeDualCreatedHierarchy); 111 FRIEND_TEST_ALL_PREFIXES(SyncerTest, LongChangelistWithApplicationConflict); 112 FRIEND_TEST_ALL_PREFIXES(SyncerTest, DeletingEntryWithLocalEdits); 113 FRIEND_TEST_ALL_PREFIXES(EntryCreatedInNewFolderTest, 114 EntryCreatedInNewFolderMidSync); 115 116 DISALLOW_COPY_AND_ASSIGN(Syncer); 117 }; 118 119 } // namespace syncer 120 121 #endif // SYNC_ENGINE_SYNCER_H_ 122