chromecast/browser/metrics/external_metrics.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 CHROMECAST_BROWSER_METRICS_EXTERNAL_METRICS_H_
   6 #define CHROMECAST_BROWSER_METRICS_EXTERNAL_METRICS_H_
   7
   8 #include <string>
   9
  10 #include "base/macros.h"
  11 #include "base/memory/weak_ptr.h"
  12
  13 namespace metrics {
  14 class MetricSample;
  15 }  // namespace metrics
  16
  17 namespace chromecast {
  18 namespace metrics {
  19
  20 class CastStabilityMetricsProvider;
  21
  22 // ExternalMetrics service allows processes outside of the Chromecast browser
  23 // process to upload metrics via reading/writing to a known shared file.
  24 class ExternalMetrics {
  25  public:
  26   explicit ExternalMetrics(CastStabilityMetricsProvider* stability_provider,
  27                            const std::string& uma_events_file);
  28   // Begins external data collection. Calls to RecordAction originate in the
  29   // File thread but are executed in the UI thread.
  30   void Start();
  31
  32   // Destroys itself in appropriate thread.
  33   void StopAndDestroy();
  34
  35  private:
  36   friend class base::DeleteHelper<ExternalMetrics>;
  37
  38   ~ExternalMetrics();
  39
  40   // The max length of a message (name-value pair, plus header)
  41   static const int kMetricsMessageMaxLength = 1024;  // be generous
  42
  43   // Records an external crash of the given string description.
  44   void RecordCrash(const std::string& crash_kind);
  45
  46   // Records a sparse histogram. |sample| is expected to be a sparse histogram.
  47   void RecordSparseHistogram(const ::metrics::MetricSample& sample);
  48
  49   // Collects external events from metrics log file.  This is run at periodic
  50   // intervals.
  51   //
  52   // Returns the number of events collected.
  53   int CollectEvents();
  54
  55   // Calls CollectEvents and reschedules a future collection.
  56   void CollectEventsAndReschedule();
  57
  58   // Reference to stability metrics provider, for reporting external crashes.
  59   CastStabilityMetricsProvider* const stability_provider_;
  60
  61   // File used by libmetrics to send metrics to the browser process.
  62   const std::string uma_events_file_;
  63
  64   base::WeakPtrFactory<ExternalMetrics> weak_factory_;
  65
  66   DISALLOW_COPY_AND_ASSIGN(ExternalMetrics);
  67 };
  68
  69 }  // namespace metrics
  70 }  // namespace chromecast
  71
  72 #endif  // CHROMECAST_BROWSER_METRICS_EXTERNAL_METRICS_H_