Add UMA metrics to the site engagement service.

chrome/browser/engagement/site_engagement_service.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SERVICE_H_
 #define CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SERVICE_H_
 
 #include <map>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
+#include "chrome/browser/engagement/site_engagement_metrics.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "ui/base/page_transition_types.h"
 
 namespace base {
 class DictionaryValue;
 class Clock;
 }
 
 class GURL;
 class Profile;
@@ skipping 27 matching lines @@
   // The SiteEngagementService does not take ownership of |clock|. It is the
   // responsibility of the caller to make sure |clock| outlives this
   // SiteEngagementScore.
   SiteEngagementScore(base::Clock* clock,
                       const base::DictionaryValue& score_dict);
   ~SiteEngagementScore();
 
   double Score() const;
   void AddPoints(double points);
 
+  // Returns true if the maximum number of points today has been added.
+  bool MaxPointsPerDayAdded();
+
   // Updates the content settings dictionary |score_dict| with the current score
   // fields. Returns true if |score_dict| changed, otherwise return false.
   bool UpdateScoreDict(base::DictionaryValue* score_dict);
 
  private:
   friend class SiteEngagementScoreTest;
 
   // This version of the constructor is used in unit tests.
   explicit SiteEngagementScore(base::Clock* clock);
 
@@ skipping 51 matching lines @@
   ~SiteEngagementService() override;
 
   // Returns a map of all stored origins and their engagement scores.
   std::map<GURL, double> GetScoreMap();
 
   // Update the karma score of the origin matching |url| for navigation.
   void HandleNavigation(const GURL& url, ui::PageTransition transition);
 
   // Update the karma score of the origin matching |url| for time-on-site, based
   // on user input.
-  void HandleUserInput(const GURL& url);
+  void HandleUserInput(const GURL& url,
+                       SiteEngagementMetrics::EngagementType type);
 
   // Overridden from SiteEngagementScoreProvider:
   double GetScore(const GURL& url) override;
   double GetTotalEngagementPoints() override;
 
  private:
+  FRIEND_TEST_ALL_PREFIXES(SiteEngagementServiceTest, GetMedianEngagement);
   FRIEND_TEST_ALL_PREFIXES(SiteEngagementServiceTest, CleanupEngagementScores);
+  FRIEND_TEST_ALL_PREFIXES(SiteEngagementServiceTest,
+                           GetNavigationPointsAndHistograms);
+  FRIEND_TEST_ALL_PREFIXES(SiteEngagementServiceTest,
+                           GetUserInputPointsAndHistograms);
 
   // Only used in tests.
   SiteEngagementService(Profile* profile, scoped_ptr<base::Clock> clock);
 
   // Adds the specified number of points to the given origin, respecting the
   // maximum limits for the day and overall.
   void AddPoints(const GURL& url, double points);
 
+  // Post startup tasks: cleaning up origins which have decayed to 0, and
+  // logging UMA statistics.
+  void AfterStartupTask();
   void CleanupEngagementScores();
+  void RecordMetrics();
+
+  // Returns the median engagement score of all recorded origins.
+  double GetMedianEngagement(std::map<GURL, double>& score_map);
+
+  // Returns the number of origins with maximum daily and total engagement
+  // respectively.
+  int OriginsWithMaxDailyEngagement();
+  int OriginsWithMaxEngagement(std::map<GURL, double>& score_map);
 
   Profile* profile_;
 
   // The clock used to vend times.
   scoped_ptr<base::Clock> clock_;
 
+  // Metrics are recorded at non-incognito browser startup, and then
+  // approximately once per hour thereafter. Store the local time at which
+  // metrics were previously uploaded: the first event which affects any
+  // origin's engagement score after an hour has elapsed triggers the next
+  // upload.
+  base::Time last_metrics_time_;
+
   base::WeakPtrFactory<SiteEngagementService> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SiteEngagementService);
 };
 
 #endif  // CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SERVICE_H_