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.
5 // A class to track the outstanding work required to bring the client back into
6 // sync with the server.
7 #ifndef SYNC_SESSIONS_NUDGE_TRACKER_H_
8 #define SYNC_SESSIONS_NUDGE_TRACKER_H_
13 #include "base/compiler_specific.h"
14 #include "sync/base/sync_export.h"
15 #include "sync/internal_api/public/base/model_type.h"
16 #include "sync/protocol/sync.pb.h"
17 #include "sync/sessions/data_type_tracker.h"
21 class ObjectIdInvalidationMap;
25 class SYNC_EXPORT_PRIVATE NudgeTracker {
27 static size_t kDefaultMaxPayloadsPerType;
32 // Returns true if there is a good reason for performing a sync cycle.
33 // This does not take into account whether or not this is a good *time* to
34 // perform a sync cycle; that's the scheduler's job.
35 bool IsSyncRequired() const;
37 // Returns true if there is a good reason for performing a get updates
38 // request as part of the next sync cycle.
39 bool IsGetUpdatesRequired() const;
41 // Return true if should perform a sync cycle for GU retry.
43 // This is sensitive to changes in 'current time'. Its value can be affected
44 // by SetSyncCycleStartTime(), SetNextRetryTime(), and
45 // RecordSuccessfulSyncCycle(). Please refer to those functions for more
46 // information on how this flag is maintained.
47 bool IsRetryRequired() const;
49 // Tells this class that all required update fetching or committing has
50 // completed successfully.
51 void RecordSuccessfulSyncCycle();
53 // Takes note of a local change.
54 void RecordLocalChange(ModelTypeSet types);
56 // Takes note of a locally issued request to refresh a data type.
57 void RecordLocalRefreshRequest(ModelTypeSet types);
59 // Takes note of the receipt of an invalidation notice from the server.
60 void RecordRemoteInvalidation(
61 const ObjectIdInvalidationMap& invalidation_map);
63 // These functions should be called to keep this class informed of the status
64 // of the connection to the invalidations server.
65 void OnInvalidationsEnabled();
66 void OnInvalidationsDisabled();
68 // Marks |types| as being throttled from |now| until |now| + |length|.
69 void SetTypesThrottledUntil(ModelTypeSet types,
70 base::TimeDelta length,
73 // Removes any throttling that have expired by time |now|.
74 void UpdateTypeThrottlingState(base::TimeTicks now);
76 // Returns the time of the next type unthrottling, relative to
77 // the input |now| value.
78 base::TimeDelta GetTimeUntilNextUnthrottle(base::TimeTicks now) const;
80 // Returns true if any type is currenlty throttled.
81 bool IsAnyTypeThrottled() const;
83 // Returns true if |type| is currently throttled.
84 bool IsTypeThrottled(ModelType type) const;
86 // Returns the set of currently throttled types.
87 ModelTypeSet GetThrottledTypes() const;
89 // Returns the 'source' of the GetUpdate request.
91 // This flag is deprecated, but still used by the server. There can be more
92 // than one reason to perform a particular sync cycle. The GetUpdatesTrigger
93 // message will contain more reliable information about the reasons for
96 // See the implementation for important information about the coalesce logic.
97 sync_pb::GetUpdatesCallerInfo::GetUpdatesSource updates_source() const;
99 // Fills a GetUpdatesTrigger message for the next GetUpdates request. This is
100 // used by the DownloadUpdatesCommand to dump lots of useful per-type state
101 // information into the GetUpdate request before sending it off to the server.
102 void FillProtoMessage(
104 sync_pb::GetUpdateTriggers* msg) const;
106 // Fills a ProgressMarker with single legacy notification hint expected by the
107 // sync server. Newer servers will rely on the data set by FillProtoMessage()
109 void SetLegacyNotificationHint(
111 sync_pb::DataTypeProgressMarker* progress) const;
113 // Flips the flag if we're due for a retry.
114 void SetSyncCycleStartTime(base::TimeTicks now);
116 // Adjusts the number of hints that can be stored locally.
117 void SetHintBufferSize(size_t size);
119 // Schedules a retry GetUpdate request for some time in the future.
121 // This is a request sent to us as part of a server response requesting
122 // that the client perform a GetUpdate request at |next_retry_time| to
123 // fetch any updates it may have missed in the first attempt.
125 // To avoid strange results from IsRetryRequired() during a sync cycle, the
126 // effects of this change are not guaranteed to take effect until
127 // SetSyncCycleStartTime() is called at the start of the *next* sync cycle.
128 void SetNextRetryTime(base::TimeTicks next_retry_time);
131 typedef std::map<ModelType, DataTypeTracker> TypeTrackerMap;
133 TypeTrackerMap type_trackers_;
135 // Merged updates source. This should be obsolete, but the server still
136 // relies on it for some heuristics.
137 sync_pb::GetUpdatesCallerInfo::GetUpdatesSource updates_source_;
139 // Tracks whether or not invalidations are currently enabled.
140 bool invalidations_enabled_;
142 // This flag is set if suspect that some technical malfunction or known bug
143 // may have left us with some unserviced invalidations.
145 // Keeps track of whether or not we're fully in sync with the invalidation
146 // server. This can be false even if invalidations are enabled and working
147 // correctly. For example, until we get ack-tracking working properly, we
148 // won't persist invalidations between restarts, so we may be out of sync when
149 // we restart. The only way to get back into sync is to have invalidations
150 // enabled, then complete a sync cycle to make sure we're fully up to date.
151 bool invalidations_out_of_sync_;
153 size_t num_payloads_per_type_;
155 base::TimeTicks last_successful_sync_time_;
157 // A pending update to the current_retry_time_.
159 // The GU retry time is specified by a call to SetNextRetryTime, but we don't
160 // want that change to take effect right away, since it could happen in the
161 // middle of a sync cycle. We delay the update until the start of the next
162 // sync cycle, which is indicated by a call to SetSyncCycleStartTime().
163 base::TimeTicks next_retry_time_;
165 // The currently active retry GU time. Will be null if there is no retry GU
166 // pending at this time.
167 base::TimeTicks current_retry_time_;
169 // The time when the sync cycle started. This value is maintained by
170 // SetSyncCycleStartTime(). This may contain a stale value if we're not
171 // currently in a sync cycle.
172 base::TimeTicks sync_cycle_start_time_;
174 DISALLOW_COPY_AND_ASSIGN(NudgeTracker);
177 } // namespace sessions
178 } // namespace syncer
180 #endif // SYNC_SESSIONS_NUDGE_TRACKER_H_