1 // Copyright 2013 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 // A class to track the per-type scheduling data. 6 #ifndef SYNC_SESSIONS_DATA_TYPE_TRACKER_H_ 7 #define SYNC_SESSIONS_DATA_TYPE_TRACKER_H_ 8 9 #include <deque> 10 #include <string> 11 12 #include "base/basictypes.h" 13 #include "base/time/time.h" 14 #include "sync/notifier/dropped_invalidation_tracker.h" 15 #include "sync/notifier/single_object_invalidation_set.h" 16 #include "sync/protocol/sync.pb.h" 17 18 namespace syncer { 19 20 class Invalidation; 21 class SingleObjectInvalidationSet; 22 23 namespace sessions { 24 25 typedef std::deque<std::string> PayloadList; 26 27 class DataTypeTracker { 28 public: 29 explicit DataTypeTracker(const invalidation::ObjectId& object_id); 30 ~DataTypeTracker(); 31 32 // For STL compatibility, we do not forbid the creation of a default copy 33 // constructor and assignment operator. 34 35 // Tracks that a local change has been made to this type. 36 void RecordLocalChange(); 37 38 // Tracks that a local refresh request has been made for this type. 39 void RecordLocalRefreshRequest(); 40 41 // Tracks that we received invalidation notifications for this type. 42 void RecordRemoteInvalidations( 43 const SingleObjectInvalidationSet& invalidations); 44 45 // Records that a sync cycle has been performed successfully. 46 // Generally, this means that all local changes have been committed and all 47 // remote changes have been downloaded, so we can clear any flags related to 48 // pending work. 49 void RecordSuccessfulSyncCycle(); 50 51 // Updates the size of the invalidations payload buffer. 52 void UpdatePayloadBufferSize(size_t new_size); 53 54 // Returns true if there is a good reason to perform a sync cycle. This does 55 // not take into account whether or not now is a good time to perform a sync 56 // cycle. That's for the scheduler to decide. 57 bool IsSyncRequired() const; 58 59 // Returns true if there is a good reason to fetch updates for this type as 60 // part of the next sync cycle. 61 bool IsGetUpdatesRequired() const; 62 63 // Returns true if there is an uncommitted local change. 64 bool HasLocalChangePending() const; 65 66 // Returns true if we've received an invalidation since we last fetched 67 // updates. 68 bool HasPendingInvalidation() const; 69 70 // Returns true if an explicit refresh request is still outstanding. 71 bool HasRefreshRequestPending() const; 72 73 // Fills in the legacy invalidaiton payload information fields. 74 void SetLegacyNotificationHint( 75 sync_pb::DataTypeProgressMarker* progress) const; 76 77 // Fills some type-specific contents of a GetUpdates request protobuf. These 78 // messages provide the server with the information it needs to decide how to 79 // handle a request. 80 void FillGetUpdatesTriggersMessage(sync_pb::GetUpdateTriggers* msg) const; 81 82 // Returns true if the type is currently throttled. 83 bool IsThrottled() const; 84 85 // Returns the time until this type's throttling interval expires. Should not 86 // be called unless IsThrottled() returns true. The returned value will be 87 // increased to zero if it would otherwise have been negative. 88 base::TimeDelta GetTimeUntilUnthrottle(base::TimeTicks now) const; 89 90 // Throttles the type from |now| until |now| + |duration|. 91 void ThrottleType(base::TimeDelta duration, base::TimeTicks now); 92 93 // Unthrottles the type if |now| >= the throttle expiry time. 94 void UpdateThrottleState(base::TimeTicks now); 95 96 private: 97 // Number of local change nudges received for this type since the last 98 // successful sync cycle. 99 int local_nudge_count_; 100 101 // Number of local refresh requests received for this type since the last 102 // successful sync cycle. 103 int local_refresh_request_count_; 104 105 // The list of invalidations received since the last successful sync cycle. 106 // This list may be incomplete. See also: 107 // drop_tracker_.IsRecoveringFromDropEvent() and server_payload_overflow_. 108 SingleObjectInvalidationSet pending_invalidations_; 109 110 size_t payload_buffer_size_; 111 112 // If !unthrottle_time_.is_null(), this type is throttled and may not download 113 // or commit data until the specified time. 114 base::TimeTicks unthrottle_time_; 115 116 // A helper to keep track invalidations we dropped due to overflow. 117 DroppedInvalidationTracker drop_tracker_; 118 }; 119 120 } // namespace syncer 121 } // namespace sessions 122 123 #endif // SYNC_SESSIONS_DATA_TYPE_TRACKER_H_ 124