chrome/browser/chromeos/external_metrics.h

   1 // Copyright (c) 2010 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_CHROMEOS_EXTERNAL_METRICS_H_
   6 #define CHROME_BROWSER_CHROMEOS_EXTERNAL_METRICS_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/containers/hash_tables.h"
  13 #include "base/files/file_path.h"
  14 #include "base/gtest_prod_util.h"
  15 #include "base/memory/ref_counted.h"
  16
  17 namespace chromeos {
  18
  19 // ExternalMetrics is a service that Chrome offers to Chrome OS to upload
  20 // metrics to the UMA server on its behalf.  Chrome periodically reads the
  21 // content of a well-know file, and parses it into name-value pairs, each
  22 // representing a Chrome OS metrics event. The events are logged using the
  23 // normal UMA mechanism. The file is then truncated to zero size. Chrome uses
  24 // flock() to synchronize accesses to the file.
  25 class ExternalMetrics : public base::RefCountedThreadSafe<ExternalMetrics> {
  26  public:
  27   ExternalMetrics();
  28
  29   // Begins the external data collection.  This service is started and stopped
  30   // by the chrome metrics service.  Calls to RecordAction originate in the
  31   // File thread but are executed in the UI thread.
  32   void Start();
  33
  34  private:
  35   friend class base::RefCountedThreadSafe<ExternalMetrics>;
  36   FRIEND_TEST_ALL_PREFIXES(ExternalMetricsTest, ParseExternalMetricsFile);
  37
  38   // There is one function with this type for each action.
  39   typedef void (*RecordFunctionType)();
  40
  41   typedef void (*RecorderType)(const char*, const char*);  // For testing only.
  42
  43   // The max length of a message (name-value pair, plus header)
  44   static const int kMetricsMessageMaxLength = 1024;  // be generous
  45
  46   ~ExternalMetrics();
  47
  48   // Passes an action event to the UMA service on the UI thread.
  49   void RecordActionUI(std::string action_string);
  50
  51   // Passes an action event to the UMA service.
  52   void RecordAction(const char* action_name);
  53
  54   // Records an external crash of the given string description to
  55   // UMA service on the UI thread.
  56   void RecordCrashUI(const std::string& crash_kind);
  57
  58   // Records an external crash of the given string description.
  59   void RecordCrash(const std::string& crash_kind);
  60
  61   // Passes an histogram event to the UMA service.  |histogram_data| is in the
  62   // form <histogram-name> <sample> <min> <max> <buckets_count>.
  63   void RecordHistogram(const char* histogram_data);
  64
  65   // Passes a linear histogram event to the UMA service.  |histogram_data| is
  66   // in the form <histogram-name> <sample> <max>.
  67   void RecordLinearHistogram(const char* histogram_data);
  68
  69   // Passes a sparse histogram event to the UMA service.  |histogram_data| is
  70   // in the form <histogram-name> <sample>.
  71   void RecordSparseHistogram(const char* histogram_data);
  72
  73   // Collects external events from metrics log file.  This is run at periodic
  74   // intervals.
  75   void CollectEvents();
  76
  77   // Calls CollectEvents and reschedules a future collection.
  78   void CollectEventsAndReschedule();
  79
  80   // Schedules a metrics event collection in the future.
  81   void ScheduleCollector();
  82
  83   // Calls setup methods for Chrome OS field trials that need to be initialized
  84   // based on data from the file system.  They are setup here so that we can
  85   // make absolutely sure that they are setup before we gather UMA statistics
  86   // from ChromeOS.
  87   void SetupFieldTrialsOnFileThread();
  88
  89   // Maps histogram or action names to recorder structs.
  90   base::hash_map<std::string, RecordFunctionType> action_recorders_;
  91
  92   // Set containing known user actions.
  93   base::hash_set<std::string> valid_user_actions_;
  94
  95   // Used for testing only.
  96   RecorderType test_recorder_;
  97   base::FilePath test_path_;
  98
  99   DISALLOW_COPY_AND_ASSIGN(ExternalMetrics);
 100 };
 101
 102 }  // namespace chromeos
 103
 104 #endif  // CHROME_BROWSER_CHROMEOS_EXTERNAL_METRICS_H_