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