components/rappor/rappor_service.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_RAPPOR_RAPPOR_SERVICE_H_
   6 #define COMPONENTS_RAPPOR_RAPPOR_SERVICE_H_
   7
   8 #include <map>
   9 #include <string>
  10
  11 #include "base/basictypes.h"
  12 #include "base/callback.h"
  13 #include "base/macros.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/timer/timer.h"
  16 #include "components/metrics/daily_event.h"
  17 #include "components/rappor/rappor_parameters.h"
  18
  19 class PrefRegistrySimple;
  20 class PrefService;
  21
  22 namespace net {
  23 class URLRequestContextGetter;
  24 }
  25
  26 namespace rappor {
  27
  28 class LogUploader;
  29 class RapporMetric;
  30 class RapporReports;
  31
  32 // The type of data stored in a metric.
  33 enum RapporType {
  34   // For sampling the eTLD+1 of a URL.
  35   ETLD_PLUS_ONE_RAPPOR_TYPE = 0,
  36   COARSE_RAPPOR_TYPE,
  37   NUM_RAPPOR_TYPES
  38 };
  39
  40 // This class provides an interface for recording samples for rappor metrics,
  41 // and periodically generates and uploads reports based on the collected data.
  42 class RapporService {
  43  public:
  44   // Constructs a RapporService.
  45   // Calling code is responsible for ensuring that the lifetime of
  46   // |pref_service| is longer than the lifetime of RapporService.
  47   // |is_incognito_callback| will be called to test if incognito mode is active.
  48   RapporService(PrefService* pref_service,
  49                 const base::Callback<bool(void)> is_incognito_callback);
  50   virtual ~RapporService();
  51
  52   // Add an observer for collecting daily metrics.
  53   void AddDailyObserver(scoped_ptr<metrics::DailyEvent::Observer> observer);
  54
  55   // Starts the periodic generation of reports and upload attempts.
  56   // |metrics enabled| should be true if UMA users have opted in.
  57   void Start(net::URLRequestContextGetter* context,
  58              bool metrics_enabled);
  59
  60   // Records a sample of the rappor metric specified by |metric_name|.
  61   // Creates and initializes the metric, if it doesn't yet exist.
  62   void RecordSample(const std::string& metric_name,
  63                     RapporType type,
  64                     const std::string& sample);
  65
  66   // Registers the names of all of the preferences used by RapporService in the
  67   // provided PrefRegistry. This should be called before calling Start().
  68   static void RegisterPrefs(PrefRegistrySimple* registry);
  69
  70  protected:
  71   // Initializes the state of the RapporService.
  72   void Initialize(int32_t cohort,
  73                   const std::string& secret,
  74                   const ReportingLevel& reporting_level);
  75
  76   // Retrieves the cohort number this client was assigned to, generating it if
  77   // doesn't already exist. The cohort should be persistent.
  78   int32_t LoadCohort();
  79
  80   // Retrieves the value for secret_ from preferences, generating it if doesn't
  81   // already exist. The secret should be persistent, so that additional bits
  82   // from the client do not get exposed over time.
  83   std::string LoadSecret();
  84
  85   // Logs all of the collected metrics to the reports proto message and clears
  86   // the internal map. Exposed for tests. Returns true if any metrics were
  87   // recorded.
  88   bool ExportMetrics(RapporReports* reports);
  89
  90   // Records a sample of the rappor metric specified by |parameters|.
  91   // Creates and initializes the metric, if it doesn't yet exist.
  92   // Exposed for tests.
  93   void RecordSampleInternal(const std::string& metric_name,
  94                             const RapporParameters& parameters,
  95                             const std::string& sample);
  96
  97  private:
  98   // Check if the service has been started successfully.
  99   bool IsInitialized() const;
 100
 101   // Called whenever the logging interval elapses to generate a new log of
 102   // reports and pass it to the uploader.
 103   void OnLogInterval();
 104
 105   // Finds a metric in the metrics_map_, creating it if it doesn't already
 106   // exist.
 107   RapporMetric* LookUpMetric(const std::string& metric_name,
 108                              const RapporParameters& parameters);
 109
 110   // A weak pointer to the PrefService used to read and write preferences.
 111   PrefService* pref_service_;
 112
 113   // A callback for testing if incognito mode is active;
 114   const base::Callback<bool(void)> is_incognito_callback_;
 115
 116   // Client-side secret used to generate fake bits.
 117   std::string secret_;
 118
 119   // The cohort this client is assigned to. -1 is uninitialized.
 120   int32_t cohort_;
 121
 122   // Timer which schedules calls to OnLogInterval().
 123   base::OneShotTimer<RapporService> log_rotation_timer_;
 124
 125   // A daily event for collecting metrics once a day.
 126   metrics::DailyEvent daily_event_;
 127
 128   // A private LogUploader instance for sending reports to the server.
 129   scoped_ptr<LogUploader> uploader_;
 130
 131   // What reporting level of metrics are being reported.
 132   ReportingLevel reporting_level_;
 133
 134   // We keep all registered metrics in a map, from name to metric.
 135   // The map owns the metrics it contains.
 136   std::map<std::string, RapporMetric*> metrics_map_;
 137
 138   DISALLOW_COPY_AND_ASSIGN(RapporService);
 139 };
 140
 141 }  // namespace rappor
 142
 143 #endif  // COMPONENTS_RAPPOR_RAPPOR_SERVICE_H_