chrome/browser/prefs/pref_metrics_service.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 CHROME_BROWSER_PREFS_PREF_METRICS_SERVICE_H_
   6 #define CHROME_BROWSER_PREFS_PREF_METRICS_SERVICE_H_
   7
   8 #include <map>
   9 #include <string>
  10
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/memory/singleton.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "chrome/browser/profiles/profile.h"
  15 #include "components/keyed_service/content/browser_context_keyed_service_factory.h"
  16 #include "components/keyed_service/core/keyed_service.h"
  17 #include "components/syncable_prefs/synced_pref_change_registrar.h"
  18
  19 class PrefRegistrySimple;
  20
  21 // PrefMetricsService is responsible for recording prefs-related UMA stats.
  22 class PrefMetricsService : public KeyedService {
  23  public:
  24   explicit PrefMetricsService(Profile* profile);
  25   ~PrefMetricsService() override;
  26
  27   class Factory : public BrowserContextKeyedServiceFactory {
  28    public:
  29     static Factory* GetInstance();
  30     static PrefMetricsService* GetForProfile(Profile* profile);
  31    private:
  32     friend struct base::DefaultSingletonTraits<Factory>;
  33
  34     Factory();
  35     ~Factory() override;
  36
  37     // BrowserContextKeyedServiceFactory implementation
  38     KeyedService* BuildServiceInstanceFor(
  39         content::BrowserContext* profile) const override;
  40     bool ServiceIsCreatedWithBrowserContext() const override;
  41     bool ServiceIsNULLWhileTesting() const override;
  42     content::BrowserContext* GetBrowserContextToUse(
  43         content::BrowserContext* context) const override;
  44   };
  45
  46  private:
  47   friend class PrefMetricsServiceTest;
  48
  49   // Function to log a Value to a histogram
  50   typedef base::Callback<void(const std::string&, const base::Value*)>
  51       LogHistogramValueCallback;
  52
  53   // For unit testing only.
  54   PrefMetricsService(Profile* profile, PrefService* local_settings);
  55
  56   // Record prefs state on browser context creation.
  57   void RecordLaunchPrefs();
  58
  59   // Register callbacks for synced pref changes.
  60   void RegisterSyncedPrefObservers();
  61
  62   // Registers a histogram logging callback for a synced pref change.
  63   void AddPrefObserver(const std::string& path,
  64                        const std::string& histogram_name_prefix,
  65                        const LogHistogramValueCallback& callback);
  66
  67   // Generic callback to observe a synced pref change.
  68   void OnPrefChanged(const std::string& histogram_name_prefix,
  69                      const LogHistogramValueCallback& callback,
  70                      const std::string& path,
  71                      bool from_sync);
  72
  73   // Callback for a boolean pref change histogram.
  74   void LogBooleanPrefChange(const std::string& histogram_name,
  75                             const base::Value* value);
  76
  77   // Callback for an integer pref change histogram.
  78   void LogIntegerPrefChange(int boundary_value,
  79                             const std::string& histogram_name,
  80                             const base::Value* value);
  81
  82   Profile* profile_;
  83   PrefService* prefs_;
  84   PrefService* local_state_;
  85
  86   scoped_ptr<syncable_prefs::SyncedPrefChangeRegistrar>
  87       synced_pref_change_registrar_;
  88
  89   base::WeakPtrFactory<PrefMetricsService> weak_factory_;
  90
  91   DISALLOW_COPY_AND_ASSIGN(PrefMetricsService);
  92 };
  93
  94 #endif  // CHROME_BROWSER_PREFS_PREF_METRICS_SERVICE_H_