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 // A class representing an attempt to synchronize the local syncable data 6 // store with a sync server. A SyncSession instance is passed as a stateful 7 // bundle throughout the sync cycle. The SyncSession is not reused across 8 // sync cycles; each cycle starts with a new one. 9 10 #ifndef SYNC_SESSIONS_SYNC_SESSION_H_ 11 #define SYNC_SESSIONS_SYNC_SESSION_H_ 12 13 #include <map> 14 #include <set> 15 #include <string> 16 #include <utility> 17 #include <vector> 18 19 #include "base/basictypes.h" 20 #include "base/memory/scoped_ptr.h" 21 #include "base/time/time.h" 22 #include "sync/base/sync_export.h" 23 #include "sync/engine/sync_cycle_event.h" 24 #include "sync/internal_api/public/base/model_type.h" 25 #include "sync/internal_api/public/engine/model_safe_worker.h" 26 #include "sync/internal_api/public/sessions/sync_session_snapshot.h" 27 #include "sync/protocol/sync_protocol_error.h" 28 #include "sync/sessions/status_controller.h" 29 #include "sync/sessions/sync_session_context.h" 30 31 namespace syncer { 32 class ModelSafeWorker; 33 class ProtocolEvent; 34 35 namespace sessions { 36 37 class NudgeTracker; 38 39 class SYNC_EXPORT_PRIVATE SyncSession { 40 public: 41 // The Delegate services events that occur during the session requiring an 42 // explicit (and session-global) action, as opposed to events that are simply 43 // recorded in per-session state. 44 class SYNC_EXPORT_PRIVATE Delegate { 45 public: 46 // The client was throttled and should cease-and-desist syncing activity 47 // until the specified time. 48 virtual void OnThrottled(const base::TimeDelta& throttle_duration) = 0; 49 50 // Some of the client's types were throttled. 51 virtual void OnTypesThrottled( 52 ModelTypeSet types, 53 const base::TimeDelta& throttle_duration) = 0; 54 55 // Silenced intervals can be out of phase with individual sessions, so the 56 // delegate is the only thing that can give an authoritative answer for 57 // "is syncing silenced right now". This shouldn't be necessary very often 58 // as the delegate ensures no session is started if syncing is silenced. 59 // ** Note ** This will return true if silencing commenced during this 60 // session and the interval has not yet elapsed, but the contract here is 61 // solely based on absolute time values. So, this cannot be used to infer 62 // that any given session _instance_ is silenced. An example of reasonable 63 // use is for UI reporting. 64 virtual bool IsCurrentlyThrottled() = 0; 65 66 // The client has been instructed to change its short poll interval. 67 virtual void OnReceivedShortPollIntervalUpdate( 68 const base::TimeDelta& new_interval) = 0; 69 70 // The client has been instructed to change its long poll interval. 71 virtual void OnReceivedLongPollIntervalUpdate( 72 const base::TimeDelta& new_interval) = 0; 73 74 // The client has been instructed to change its sessions commit 75 // delay. 76 virtual void OnReceivedSessionsCommitDelay( 77 const base::TimeDelta& new_delay) = 0; 78 79 // Called for the syncer to respond to the error sent by the server. 80 virtual void OnSyncProtocolError( 81 const SyncProtocolError& sync_protocol_error) = 0; 82 83 // Called when the server wants to change the number of hints the client 84 // will buffer locally. 85 virtual void OnReceivedClientInvalidationHintBufferSize(int size) = 0; 86 87 // Called when server wants to schedule a retry GU. 88 virtual void OnReceivedGuRetryDelay(const base::TimeDelta& delay) = 0; 89 90 // Called when server requests a migration. 91 virtual void OnReceivedMigrationRequest(ModelTypeSet types) = 0; 92 93 protected: ~Delegate()94 virtual ~Delegate() {} 95 }; 96 97 // Build a session without a nudge tracker. Used for poll or configure type 98 // sync cycles. 99 static SyncSession* Build(SyncSessionContext* context, 100 Delegate* delegate); 101 ~SyncSession(); 102 103 // Builds a thread-safe and read-only copy of the current session state. 104 SyncSessionSnapshot TakeSnapshot() const; 105 SyncSessionSnapshot TakeSnapshotWithSource( 106 sync_pb::GetUpdatesCallerInfo::GetUpdatesSource legacy_updates_source) 107 const; 108 109 // Builds and sends a snapshot to the session context's listeners. 110 void SendSyncCycleEndEventNotification( 111 sync_pb::GetUpdatesCallerInfo::GetUpdatesSource source); 112 void SendEventNotification(SyncCycleEvent::EventCause cause); 113 114 void SendProtocolEvent(const ProtocolEvent& event); 115 116 // TODO(akalin): Split this into context() and mutable_context(). context()117 SyncSessionContext* context() const { return context_; } delegate()118 Delegate* delegate() const { return delegate_; } status_controller()119 const StatusController& status_controller() const { 120 return *status_controller_.get(); 121 } mutable_status_controller()122 StatusController* mutable_status_controller() { 123 return status_controller_.get(); 124 } 125 126 private: 127 SyncSession(SyncSessionContext* context, Delegate* delegate); 128 129 // The context for this session, guaranteed to outlive |this|. 130 SyncSessionContext* const context_; 131 132 // The delegate for this session, must never be NULL. 133 Delegate* const delegate_; 134 135 // Our controller for various status and error counters. 136 scoped_ptr<StatusController> status_controller_; 137 138 DISALLOW_COPY_AND_ASSIGN(SyncSession); 139 }; 140 141 } // namespace sessions 142 } // namespace syncer 143 144 #endif // SYNC_SESSIONS_SYNC_SESSION_H_ 145