components/password_manager/core/browser/facet_manager.h

   1 // Copyright 2015 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_PASSWORD_MANAGER_CORE_BROWSER_FACET_MANAGER_H_
   6 #define COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_FACET_MANAGER_H_
   7
   8 #include <set>
   9 #include <vector>
  10
  11 #include "base/macros.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/time/time.h"
  14 #include "components/password_manager/core/browser/affiliation_service.h"
  15 #include "components/password_manager/core/browser/affiliation_utils.h"
  16
  17 namespace base {
  18 class Clock;
  19 class TaskRunner;
  20 }  // namespace base
  21
  22 namespace password_manager {
  23
  24 class FacetManagerHost;
  25
  26 // Encapsulates the state and logic required for handling affiliation requests
  27 // concerning a single facet. The AffiliationBackend owns one instance for each
  28 // facet that requires attention, and it itself implements the FacetManagerHost
  29 // interface to provide shared functionality needed by all FacetManagers.
  30 class FacetManager {
  31  public:
  32   using StrategyOnCacheMiss = AffiliationService::StrategyOnCacheMiss;
  33
  34   // Both the |backend| and |clock| must outlive this object.
  35   FacetManager(const FacetURI& facet_uri,
  36                FacetManagerHost* backend,
  37                base::Clock* clock);
  38   ~FacetManager();
  39
  40   // Facet-specific implementations for methods in AffiliationService of the
  41   // same name. See documentation in affiliation_service.h for details:
  42   void GetAffiliations(
  43       StrategyOnCacheMiss cache_miss_strategy,
  44       const AffiliationService::ResultCallback& callback,
  45       const scoped_refptr<base::TaskRunner>& callback_task_runner);
  46   void Prefetch(const base::Time& keep_fresh_until);
  47   void CancelPrefetch(const base::Time& keep_fresh_until);
  48
  49   // Called when |affiliation| information regarding this facet has just been
  50   // fetched from the Affiliation API.
  51   void OnFetchSucceeded(const AffiliatedFacetsWithUpdateTime& affiliation);
  52
  53   // Called by the backend when the time specified in RequestNotificationAtTime
  54   // has come to pass, so that |this| can perform delayed administrative tasks.
  55   void NotifyAtRequestedTime();
  56
  57   // Returns whether this instance has becomes redundant, that is, it has no
  58   // more meaningful state than a newly created instance would have.
  59   bool CanBeDiscarded() const;
  60
  61   // Returns whether or not affiliation information relating to this facet needs
  62   // to be fetched right now.
  63   bool DoesRequireFetch() const;
  64
  65   // The members below are made public for the sake of tests.
  66
  67   // Returns whether or not cached data for this facet is fresh (not stale).
  68   bool IsCachedDataFresh() const;
  69
  70   // Returns whether or not cached data for this facet is near-stale or stale.
  71   bool IsCachedDataNearStale() const;
  72
  73   // The duration after which cached affiliation data is considered near-stale.
  74   static const int kCacheSoftExpiryInHours;
  75
  76   // The duration after which cached affiliation data is considered stale.
  77   static const int kCacheHardExpiryInHours;
  78
  79  private:
  80   struct RequestInfo;
  81
  82   // Returns the time when the cached data for this facet will become stale.
  83   // The data is considered stale with the returned time value inclusive.
  84   base::Time GetCacheHardExpiryTime() const;
  85
  86   // Returns the time when cached data for this facet becomes near-stale.
  87   // The data is considered near-stale with the returned time value inclusive.
  88   base::Time GetCacheSoftExpiryTime() const;
  89
  90   // Returns the maximum of |keep_fresh_thresholds_|, or the NULL time if the
  91   // set is empty.
  92   base::Time GetMaximumKeepFreshUntilThreshold() const;
  93
  94   // Returns the next time affiliation data for this facet needs to be fetched
  95   // due to active prefetch requests, or base::Time::Max() if not at all.
  96   base::Time GetNextRequiredFetchTimeDueToPrefetch() const;
  97
  98   // Posts the callback of the request described by |request_info| with success.
  99   static void ServeRequestWithSuccess(const RequestInfo& request_info,
 100                                       const AffiliatedFacets& affiliation);
 101
 102   // Posts the callback of the request described by |request_info| with failure.
 103   static void ServeRequestWithFailure(const RequestInfo& request_info);
 104
 105   FacetURI facet_uri_;
 106   FacetManagerHost* backend_;
 107   base::Clock* clock_;
 108
 109   // The last time affiliation information was fetched for this facet, i.e. the
 110   // freshness of the data in the cache. If there is no corresponding data in
 111   // the database, this will contain the NULL time. Otherwise, the update time
 112   // in the database should match this value; it is stored to reduce disk I/O.
 113   base::Time last_update_time_;
 114
 115   // Contains information about the GetAffiliations() requests that are waiting
 116   // for the result of looking up this facet.
 117   std::vector<RequestInfo> pending_requests_;
 118
 119   // Keeps track of |keep_fresh_until| thresholds corresponding to Prefetch()
 120   // requests for this facet. Affiliation information for this facet must be
 121   // kept fresh by periodic refetches until at least the maximum time in this
 122   // set (exclusive).
 123   //
 124   // This is not a single timestamp but rather a multiset so that cancellation
 125   // of individual prefetches can be supported even if there are two requests
 126   // with the same |keep_fresh_until| threshold.
 127   std::multiset<base::Time> keep_fresh_until_thresholds_;
 128
 129   DISALLOW_COPY_AND_ASSIGN(FacetManager);
 130 };
 131
 132 }  // namespace password_manager
 133 #endif  // COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_FACET_MANAGER_H_