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/macros.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/timer/timer.h"
  15
  16 class PrefRegistrySimple;
  17 class PrefService;
  18
  19 namespace net {
  20 class URLRequestContextGetter;
  21 }
  22
  23 namespace rappor {
  24
  25 class LogUploader;
  26 class RapporMetric;
  27 class RapporReports;
  28 struct RapporParameters;
  29
  30 // The type of data stored in a metric.
  31 enum RapporType {
  32   // For sampling the eTLD+1 of a URL.
  33   ETLD_PLUS_ONE_RAPPOR_TYPE = 0,
  34   NUM_RAPPOR_TYPES
  35 };
  36
  37 // This class provides an interface for recording samples for rappor metrics,
  38 // and periodically generates and uploads reports based on the collected data.
  39 class RapporService {
  40  public:
  41   RapporService();
  42   virtual ~RapporService();
  43
  44   // Starts the periodic generation of reports and upload attempts.
  45   void Start(PrefService* pref_service, net::URLRequestContextGetter* context);
  46
  47   // Records a sample of the rappor metric specified by |metric_name|.
  48   // Creates and initializes the metric, if it doesn't yet exist.
  49   void RecordSample(const std::string& metric_name,
  50                     RapporType type,
  51                     const std::string& sample);
  52
  53   // Sets the cohort value.  For use by tests only.
  54   void SetCohortForTesting(uint32_t cohort) { cohort_ = cohort; }
  55
  56   // Sets the secret value.  For use by tests only.
  57   void SetSecretForTesting(const std::string& secret) { secret_ = secret; }
  58
  59   // Registers the names of all of the preferences used by RapporService in the
  60   // provided PrefRegistry. This should be called before calling Start().
  61   static void RegisterPrefs(PrefRegistrySimple* registry);
  62
  63  protected:
  64   // Logs all of the collected metrics to the reports proto message and clears
  65   // the internal map.  Exposed for tests.  Returns true if any metrics were
  66   // recorded.
  67   bool ExportMetrics(RapporReports* reports);
  68
  69   // Records a sample of the rappor metric specified by |parameters|.
  70   // Creates and initializes the metric, if it doesn't yet exist.
  71   // Exposed for tests.
  72   void RecordSampleInternal(const std::string& metric_name,
  73                             const RapporParameters& parameters,
  74                             const std::string& sample);
  75
  76  private:
  77   // Check if the service has been started successfully.
  78   bool IsInitialized() const;
  79
  80   // Retrieves the cohort number this client was assigned to, generating it if
  81   // doesn't already exist.  The cohort should be persistent.
  82   void LoadCohort(PrefService* pref_service);
  83
  84   // Retrieves the value for secret_ from preferences, generating it if doesn't
  85   // already exist.  The secret should be persistent, so that additional bits
  86   // from the client do not get exposed over time.
  87   void LoadSecret(PrefService* pref_service);
  88
  89   // Called whenever the logging interval elapses to generate a new log of
  90   // reports and pass it to the uploader.
  91   void OnLogInterval();
  92
  93   // Finds a metric in the metrics_map_, creating it if it doesn't already
  94   // exist.
  95   RapporMetric* LookUpMetric(const std::string& metric_name,
  96                              const RapporParameters& parameters);
  97
  98   // Client-side secret used to generate fake bits.
  99   std::string secret_;
 100
 101   // The cohort this client is assigned to. -1 is uninitialized.
 102   int32_t cohort_;
 103
 104   // Timer which schedules calls to OnLogInterval().
 105   base::OneShotTimer<RapporService> log_rotation_timer_;
 106
 107   // A private LogUploader instance for sending reports to the server.
 108   scoped_ptr<LogUploader> uploader_;
 109
 110   // We keep all registered metrics in a map, from name to metric.
 111   // The map owns the metrics it contains.
 112   std::map<std::string, RapporMetric*> metrics_map_;
 113
 114   DISALLOW_COPY_AND_ASSIGN(RapporService);
 115 };
 116
 117 }  // namespace rappor
 118
 119 #endif  // COMPONENTS_RAPPOR_RAPPOR_SERVICE_H_