[Most Visited] Log suggestion provider to UMA

chrome/browser/search/most_visited_iframe_source.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/search/most_visited_iframe_source.h"
 
 #include "base/metrics/histogram.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/stringprintf.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/user_metrics.h"
 #include "grit/browser_resources.h"
 #include "net/base/url_util.h"
 #include "url/gurl.h"
 
 namespace {
 
 const char kTitleHTMLPath[] = "/title.html";
 const char kTitleCSSPath[] = "/title.css";
 const char kTitleJSPath[] = "/title.js";
 const char kThumbnailHTMLPath[] = "/thumbnail.html";
 const char kThumbnailCSSPath[] = "/thumbnail.css";
 const char kThumbnailJSPath[] = "/thumbnail.js";
 const char kUtilJSPath[] = "/util.js";
 const char kCommonCSSPath[] = "/common.css";
 const char kLogHTMLPath[] = "/log.html";
+const char kMostVisitedHistogramWithProvider[] = "NewTabPage.MostVisited.%s";
 
 }  // namespace
 
 MostVisitedIframeSource::MostVisitedIframeSource() {
 }
 
 MostVisitedIframeSource::~MostVisitedIframeSource() {
 }
 
 const int MostVisitedIframeSource::kNumMostVisited = 8;
@@ skipping 26 matching lines @@
   } else if (path == kUtilJSPath) {
     SendResource(IDR_MOST_VISITED_UTIL_JS, callback);
   } else if (path == kCommonCSSPath) {
     SendResource(IDR_MOST_VISITED_IFRAME_CSS, callback);
   } else if (path == kLogHTMLPath) {
     // Log the clicked MostVisited element by position.
     std::string str_position;
     int position;
     if (net::GetValueForKeyInQuery(url, "pos", &str_position) &&
         base::StringToInt(str_position, &position)) {
+      // Log the Most Visited click.
       UMA_HISTOGRAM_ENUMERATION(kMostVisitedHistogramName, position,
                                 kNumMostVisited);
+      // If a specific provider is specified, log the metric specific to the
+      // provider.
+      std::string provider;
+      if (net::GetValueForKeyInQuery(url, "pr", &provider))
+        LogMostVisitedProviderClick(position, provider);
+
       // Records the action. This will be available as a time-stamped stream
       // server-side and can be used to compute time-to-long-dwell.
       content::RecordAction(content::UserMetricsAction("MostVisited_Clicked"));
     }
     callback.Run(NULL);
   } else {
     callback.Run(NULL);
   }
 }
 
 bool MostVisitedIframeSource::ServesPath(const std::string& path) const {
   return path == kTitleHTMLPath || path == kTitleCSSPath ||
          path == kTitleJSPath || path == kThumbnailHTMLPath ||
          path == kThumbnailCSSPath || path == kThumbnailJSPath ||
          path == kUtilJSPath || path == kCommonCSSPath || path == kLogHTMLPath;
 }
+
+void MostVisitedIframeSource::LogMostVisitedProviderClick(
+    int position,
+    const std::string& provider) {
+  std::string histogram_name =
+      MostVisitedIframeSource::GetHistogramNameForProvider(provider);
+  base::HistogramBase* counter = base::LinearHistogram::FactoryGet(
+      histogram_name, 1,
+      MostVisitedIframeSource::kNumMostVisited,
+      MostVisitedIframeSource::kNumMostVisited + 1,

[Jered, 2013/12/13 21:37:59]

Aren't there only n and not n+1 buckets?

[Mathieu, 2013/12/13 21:48:26]

Spoke with Alexei, he said it's best to follow what the macro is doing
(https://code.google.com/p/chromium/codesearch#chromium/src/base/metrics/histo...,
which is what I have here), and the API over there is a bit weird (there may be
an implicit 0 bucket...). To be safe, will leave as is.

+      base::Histogram::kUmaTargetedHistogramFlag);
+  counter->Add(position);
+}
+
+// static
+std::string MostVisitedIframeSource::GetHistogramNameForProvider(
+    const std::string& provider) {
+  return base::StringPrintf(kMostVisitedHistogramWithProvider,
+                            provider.c_str());
+}