components/invalidation/unacked_invalidation_set.h

   1 // Copyright 2014 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 COMPONENTS_INVALIDATION_UNACKED_INVALIDATION_SET_H_
   6 #define COMPONENTS_INVALIDATION_UNACKED_INVALIDATION_SET_H_
   7
   8 #include <set>
   9
  10 #include "base/memory/weak_ptr.h"
  11 #include "base/single_thread_task_runner.h"
  12 #include "components/invalidation/invalidation.h"
  13 #include "components/invalidation/invalidation_export.h"
  14 #include "components/invalidation/invalidation_util.h"
  15
  16 namespace base {
  17 class DictionaryValue;
  18 }  // namespace base
  19
  20 namespace syncer {
  21
  22 namespace test_util {
  23 class UnackedInvalidationSetEqMatcher;
  24 }  // test_util
  25
  26 class SingleObjectInvalidationSet;
  27 class ObjectIdInvalidationMap;
  28 class AckHandle;
  29
  30 // Manages the set of invalidations that are awaiting local acknowledgement for
  31 // a particular ObjectId.  This set of invalidations will be persisted across
  32 // restarts, though this class is not directly responsible for that.
  33 class INVALIDATION_EXPORT UnackedInvalidationSet {
  34  public:
  35   static const size_t kMaxBufferedInvalidations;
  36
  37   UnackedInvalidationSet(invalidation::ObjectId id);
  38   UnackedInvalidationSet(const UnackedInvalidationSet& other);
  39   ~UnackedInvalidationSet();
  40
  41   // Returns the ObjectID of the invalidations this class is tracking.
  42   const invalidation::ObjectId& object_id() const;
  43
  44   // Adds a new invalidation to the set awaiting acknowledgement.
  45   void Add(const Invalidation& invalidation);
  46
  47   // Adds many new invalidations to the set awaiting acknowledgement.
  48   void AddSet(const SingleObjectInvalidationSet& invalidations);
  49
  50   // Exports the set of invalidations awaiting acknowledgement as an
  51   // ObjectIdInvalidationMap.  Each of these invalidations will be associated
  52   // with the given |ack_handler|.
  53   //
  54   // The contents of the UnackedInvalidationSet are not directly modified by
  55   // this procedure, but the AckHandles stored in those exported invalidations
  56   // are likely to end up back here in calls to Acknowledge() or Drop().
  57   void ExportInvalidations(
  58       base::WeakPtr<AckHandler> ack_handler,
  59       scoped_refptr<base::SingleThreadTaskRunner> ack_handler_task_runner,
  60       ObjectIdInvalidationMap* out) const;
  61
  62   // Removes all stored invalidations from this object.
  63   void Clear();
  64
  65   // Indicates that a handler has registered to handle these invalidations.
  66   //
  67   // Registrations with the invalidations server persist across restarts, but
  68   // registrations from InvalidationHandlers to the InvalidationService are not.
  69   // In the time immediately after a restart, it's possible that the server
  70   // will send us invalidations, and we won't have a handler to send them to.
  71   //
  72   // The SetIsRegistered() call indicates that this period has come to an end.
  73   // There is now a handler that can receive these invalidations.  Once this
  74   // function has been called, the kMaxBufferedInvalidations limit will be
  75   // ignored.  It is assumed that the handler will manage its own buffer size.
  76   void SetHandlerIsRegistered();
  77
  78   // Indicates that the handler has now unregistered itself.
  79   //
  80   // This causes the object to resume enforcement of the
  81   // kMaxBufferedInvalidations limit.
  82   void SetHandlerIsUnregistered();
  83
  84   // Given an AckHandle belonging to one of the contained invalidations, finds
  85   // the invalidation and drops it from the list.  It is considered to be
  86   // acknowledged, so there is no need to continue maintaining its state.
  87   void Acknowledge(const AckHandle& handle);
  88
  89   // Given an AckHandle belonging to one of the contained invalidations, finds
  90   // the invalidation, drops it from the list, and adds additional state to
  91   // indicate that this invalidation has been lost without being acted on.
  92   void Drop(const AckHandle& handle);
  93
  94   scoped_ptr<base::DictionaryValue> ToValue() const;
  95   bool ResetFromValue(const base::DictionaryValue& value);
  96
  97  private:
  98   // Allow this test helper to have access to our internals.
  99   friend class test_util::UnackedInvalidationSetEqMatcher;
 100
 101   typedef std::set<Invalidation, InvalidationVersionLessThan> InvalidationsSet;
 102
 103   bool ResetListFromValue(const base::ListValue& value);
 104
 105   // Limits the list size to the given maximum.  This function will correctly
 106   // update this class' internal data to indicate if invalidations have been
 107   // dropped.
 108   void Truncate(size_t max_size);
 109
 110   bool registered_;
 111   invalidation::ObjectId object_id_;
 112   InvalidationsSet invalidations_;
 113 };
 114
 115 typedef std::map<invalidation::ObjectId,
 116                  UnackedInvalidationSet,
 117                  ObjectIdLessThan> UnackedInvalidationsMap;
 118
 119 }  // namespace syncer
 120
 121 #endif  // COMPONENTS_INVALIDATION_UNACKED_INVALIDATION_SET_H_