// Copyright 2013 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. // // A class to track the outstanding work required to bring the client back into // sync with the server. #ifndef SYNC_SESSIONS_NUDGE_TRACKER_H_ #define SYNC_SESSIONS_NUDGE_TRACKER_H_ #include #include #include "base/compiler_specific.h" #include "base/memory/scoped_ptr.h" #include "sync/base/sync_export.h" #include "sync/internal_api/public/base/invalidation_interface.h" #include "sync/internal_api/public/base/model_type.h" #include "sync/protocol/sync.pb.h" #include "sync/sessions/data_type_tracker.h" namespace syncer { class ObjectIdInvalidationMap; namespace sessions { class SYNC_EXPORT_PRIVATE NudgeTracker { public: static size_t kDefaultMaxPayloadsPerType; NudgeTracker(); ~NudgeTracker(); // Returns true if there is a good reason for performing a sync cycle. // This does not take into account whether or not this is a good *time* to // perform a sync cycle; that's the scheduler's job. bool IsSyncRequired() const; // Returns true if there is a good reason for performing a get updates // request as part of the next sync cycle. bool IsGetUpdatesRequired() const; // Return true if should perform a sync cycle for GU retry. // // This is sensitive to changes in 'current time'. Its value can be affected // by SetSyncCycleStartTime(), SetNextRetryTime(), and // RecordSuccessfulSyncCycle(). Please refer to those functions for more // information on how this flag is maintained. bool IsRetryRequired() const; // Tells this class that all required update fetching or committing has // completed successfully. void RecordSuccessfulSyncCycle(); // Takes note of a local change. void RecordLocalChange(ModelTypeSet types); // Takes note of a locally issued request to refresh a data type. void RecordLocalRefreshRequest(ModelTypeSet types); // Takes note of the receipt of an invalidation notice from the server. void RecordRemoteInvalidation(syncer::ModelType type, scoped_ptr invalidation); // Take note that an initial sync is pending for this type. void RecordInitialSyncRequired(syncer::ModelType type); // These functions should be called to keep this class informed of the status // of the connection to the invalidations server. void OnInvalidationsEnabled(); void OnInvalidationsDisabled(); // Marks |types| as being throttled from |now| until |now| + |length|. void SetTypesThrottledUntil(ModelTypeSet types, base::TimeDelta length, base::TimeTicks now); // Removes any throttling that have expired by time |now|. void UpdateTypeThrottlingState(base::TimeTicks now); // Returns the time of the next type unthrottling, relative to // the input |now| value. base::TimeDelta GetTimeUntilNextUnthrottle(base::TimeTicks now) const; // Returns true if any type is currenlty throttled. bool IsAnyTypeThrottled() const; // Returns true if |type| is currently throttled. bool IsTypeThrottled(ModelType type) const; // Returns the set of currently throttled types. ModelTypeSet GetThrottledTypes() const; // Returns the set of types with local changes pending. ModelTypeSet GetNudgedTypes() const; // Returns the set of types that have pending invalidations. ModelTypeSet GetNotifiedTypes() const; // Returns the set of types that have pending refresh requests. ModelTypeSet GetRefreshRequestedTypes() const; // Returns the 'source' of the GetUpdate request. // // This flag is deprecated, but still used by the server. There can be more // than one reason to perform a particular sync cycle. The GetUpdatesTrigger // message will contain more reliable information about the reasons for // performing a sync. // // See the implementation for important information about the coalesce logic. sync_pb::GetUpdatesCallerInfo::GetUpdatesSource GetLegacySource() const; // Fills a GetUpdatesTrigger message for the next GetUpdates request. This is // used by the DownloadUpdatesCommand to dump lots of useful per-type state // information into the GetUpdate request before sending it off to the server. void FillProtoMessage( ModelType type, sync_pb::GetUpdateTriggers* msg) const; // Fills a ProgressMarker with single legacy notification hint expected by the // sync server. Newer servers will rely on the data set by FillProtoMessage() // instead of this. void SetLegacyNotificationHint( ModelType type, sync_pb::DataTypeProgressMarker* progress) const; // Flips the flag if we're due for a retry. void SetSyncCycleStartTime(base::TimeTicks now); // Adjusts the number of hints that can be stored locally. void SetHintBufferSize(size_t size); // Schedules a retry GetUpdate request for some time in the future. // // This is a request sent to us as part of a server response requesting // that the client perform a GetUpdate request at |next_retry_time| to // fetch any updates it may have missed in the first attempt. // // To avoid strange results from IsRetryRequired() during a sync cycle, the // effects of this change are not guaranteed to take effect until // SetSyncCycleStartTime() is called at the start of the *next* sync cycle. void SetNextRetryTime(base::TimeTicks next_retry_time); private: typedef std::map TypeTrackerMap; TypeTrackerMap type_trackers_; STLValueDeleter type_tracker_deleter_; // Merged updates source. This should be obsolete, but the server still // relies on it for some heuristics. sync_pb::GetUpdatesCallerInfo::GetUpdatesSource updates_source_; // Tracks whether or not invalidations are currently enabled. bool invalidations_enabled_; // This flag is set if suspect that some technical malfunction or known bug // may have left us with some unserviced invalidations. // // Keeps track of whether or not we're fully in sync with the invalidation // server. This can be false even if invalidations are enabled and working // correctly. For example, until we get ack-tracking working properly, we // won't persist invalidations between restarts, so we may be out of sync when // we restart. The only way to get back into sync is to have invalidations // enabled, then complete a sync cycle to make sure we're fully up to date. bool invalidations_out_of_sync_; size_t num_payloads_per_type_; base::TimeTicks last_successful_sync_time_; // A pending update to the current_retry_time_. // // The GU retry time is specified by a call to SetNextRetryTime, but we don't // want that change to take effect right away, since it could happen in the // middle of a sync cycle. We delay the update until the start of the next // sync cycle, which is indicated by a call to SetSyncCycleStartTime(). base::TimeTicks next_retry_time_; // The currently active retry GU time. Will be null if there is no retry GU // pending at this time. base::TimeTicks current_retry_time_; // The time when the sync cycle started. This value is maintained by // SetSyncCycleStartTime(). This may contain a stale value if we're not // currently in a sync cycle. base::TimeTicks sync_cycle_start_time_; DISALLOW_COPY_AND_ASSIGN(NudgeTracker); }; } // namespace sessions } // namespace syncer #endif // SYNC_SESSIONS_NUDGE_TRACKER_H_