sync/notifier/unacked_invalidation_set.h

   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 #ifndef SYNC_NOTIFIER_UNACKED_INVALIDATION_SET_H_
   6 #define SYNC_NOTIFIER_UNACKED_INVALIDATION_SET_H_
   7
   8 #include <vector>
   9
  10 #include "sync/base/sync_export.h"
  11 #include "sync/internal_api/public/base/invalidation.h"
  12 #include "sync/internal_api/public/util/weak_handle.h"
  13 #include "sync/notifier/invalidation_util.h"
  14
  15 namespace base {
  16 class DictionaryValue;
  17 }  // namespace base
  18
  19 namespace syncer {
  20
  21 class SingleObjectInvalidationSet;
  22 class ObjectIdInvalidationMap;
  23 class AckHandle;
  24
  25 // Manages the set of invalidations that are awaiting local acknowledgement for
  26 // a particular ObjectId.  This set of invalidations will be persisted across
  27 // restarts, though this class is not directly responsible for that.
  28 class SYNC_EXPORT UnackedInvalidationSet {
  29  public:
  30   static const size_t kMaxBufferedInvalidations;
  31
  32   UnackedInvalidationSet(invalidation::ObjectId id);
  33   ~UnackedInvalidationSet();
  34
  35   // Returns the ObjectID of the invalidations this class is tracking.
  36   const invalidation::ObjectId& object_id() const;
  37
  38   // Adds a new invalidation to the set awaiting acknowledgement.
  39   void Add(const Invalidation& invalidation);
  40
  41   // Adds many new invalidations to the set awaiting acknowledgement.
  42   void AddSet(const SingleObjectInvalidationSet& invalidations);
  43
  44   // Exports the set of invalidations awaiting acknowledgement as an
  45   // ObjectIdInvalidationMap.  Each of these invalidations will be associated
  46   // with the given |ack_handler|.
  47   //
  48   // The contents of the UnackedInvalidationSet are not directly modified by
  49   // this procedure, but the AckHandles stored in those exported invalidations
  50   // are likely to end up back here in calls to Acknowledge() or Drop().
  51   void ExportInvalidations(WeakHandle<AckHandler> ack_handler,
  52                            ObjectIdInvalidationMap* out) const;
  53
  54   // Removes all stored invalidations from this object.
  55   void Clear();
  56
  57   // Indicates that a handler has registered to handle these invalidations.
  58   //
  59   // Registrations with the invalidations server persist across restarts, but
  60   // registrations from InvalidationHandlers to the InvalidationService are not.
  61   // In the time immediately after a restart, it's possible that the server
  62   // will send us invalidations, and we won't have a handler to send them to.
  63   //
  64   // The SetIsRegistered() call indicates that this period has come to an end.
  65   // There is now a handler that can receive these invalidations.  Once this
  66   // function has been called, the kMaxBufferedInvalidations limit will be
  67   // ignored.  It is assumed that the handler will manage its own buffer size.
  68   void SetHandlerIsRegistered();
  69
  70   // Indicates that the handler has now unregistered itself.
  71   //
  72   // This causes the object to resume enforcement of the
  73   // kMaxBufferedInvalidations limit.
  74   void SetHandlerIsUnregistered();
  75
  76   // Given an AckHandle belonging to one of the contained invalidations, finds
  77   // the invalidation and drops it from the list.  It is considered to be
  78   // acknowledged, so there is no need to continue maintaining its state.
  79   void Acknowledge(const AckHandle& handle);
  80
  81   // Given an AckHandle belonging to one of the contained invalidations, finds
  82   // the invalidation, drops it from the list, and adds additional state to
  83   // indicate that this invalidation has been lost without being acted on.
  84   void Drop(const AckHandle& handle);
  85
  86   scoped_ptr<base::DictionaryValue> ToValue() const;
  87   bool ResetFromValue(const base::DictionaryValue& value);
  88
  89  private:
  90   // Allow this test helper to have access to our internals.
  91   friend class UnackedInvalidationSetEqMatcher;
  92
  93   typedef std::set<Invalidation, InvalidationVersionLessThan> InvalidationsSet;
  94
  95   bool ResetListFromValue(const base::ListValue& value);
  96
  97   // Limits the list size to the given maximum.  This function will correctly
  98   // update this class' internal data to indicate if invalidations have been
  99   // dropped.
 100   void Truncate(size_t max_size);
 101
 102   bool registered_;
 103   invalidation::ObjectId object_id_;
 104   InvalidationsSet invalidations_;
 105 };
 106
 107 typedef std::map<invalidation::ObjectId,
 108                  UnackedInvalidationSet,
 109                  ObjectIdLessThan> UnackedInvalidationsMap;
 110
 111 }  // namespace syncer
 112
 113 #endif  // SYNC_NOTIFIER_UNACKED_INVALIDATION_SET_H_