Add a histogram for tracking web store promo

chrome/browser/dom_ui/app_launcher_handler.cc

Index: chrome/browser/dom_ui/app_launcher_handler.cc
diff --git a/chrome/browser/dom_ui/app_launcher_handler.cc b/chrome/browser/dom_ui/app_launcher_handler.cc
index 9bc27d250843a7881f8d5f725dd1338701c4aa54..c32ebb3787948fa93c99953e75986cfc5ae119ea 100644
--- a/chrome/browser/dom_ui/app_launcher_handler.cc
+++ b/chrome/browser/dom_ui/app_launcher_handler.cc
@@ -5,7 +5,9 @@
 #include "chrome/browser/dom_ui/app_launcher_handler.h"
 
 #include "app/animation.h"
+#include "base/metrics/histogram.h"
 #include "base/string_number_conversions.h"
+#include "base/string_split.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
@@ -32,6 +34,11 @@
 
 namespace {
 
+// The URL prefixes used by the NTP to signal when the web store or an app
+// has launched. These are used for histogram purposes.
+const char* kLaunchAppPingURL = "record-app-launch";
+const char* kLaunchWebStorePingURL = "record-webstore-launch";
+
 // This extracts an int from a ListValue at the given |index|.
 bool ExtractInt(const ListValue* list, size_t index, int* out_int) {
   std::string string_value;
@@ -53,10 +60,21 @@ std::string GetIconURL(const Extension* extension, Extension::Icons icon,
     return default_val;
 }
 
+// Extracts the promo parameter from the |path| generated by a ping on the NTP.
+bool IsPromoActive(const std::string& path) {
+  std::vector<std::string> params;
+  base::SplitString(path, '+', &params);
+
+  CHECK(params.size() == 2);
+
+  return params.at(1) == "true";
+}
+
 }  // namespace
 
 AppLauncherHandler::AppLauncherHandler(ExtensionsService* extension_service)
-    : extensions_service_(extension_service) {
+    : extensions_service_(extension_service),
+      promo_active_(false) {
 }
 
 AppLauncherHandler::~AppLauncherHandler() {}
@@ -150,8 +168,10 @@ void AppLauncherHandler::FillAppDictionary(DictionaryValue* dictionary) {
   if (default_apps->ShouldShowPromo(extensions_service_->GetAppIds())) {
     dictionary->SetBoolean("showPromo", true);
     default_apps->DidShowPromo();
+    promo_active_ = true;
   } else {
     dictionary->SetBoolean("showPromo", false);
+    promo_active_ = false;
   }
 
   bool showLauncher =
@@ -220,6 +240,9 @@ void AppLauncherHandler::HandleLaunchApp(const ListValue* args) {
 
   if (new_contents != old_contents && browser->tab_count() > 1)
     browser->CloseTabContents(old_contents);
+
+  if (extension_id != extension_misc::kWebStoreAppId)
+    RecordAppLaunch(promo_active_);
 }
 
 void AppLauncherHandler::HandleSetLaunchType(const ListValue* args) {
@@ -271,6 +294,9 @@ void AppLauncherHandler::HandleHideAppsPromo(const ListValue* args) {
   // If the user has intentionally hidden the promotion, we'll uninstall all the
   // default apps (we know the user hasn't installed any apps on their own at
   // this point, or the promotion wouldn't have been shown).
+  UMA_HISTOGRAM_ENUMERATION(extension_misc::kAppsPromoHistogram,
+                            extension_misc::PROMO_CLOSE,
+                            extension_misc::PROMO_BUCKET_BOUNDARY);
   DefaultApps* default_apps = extensions_service_->default_apps();
   const ExtensionIdSet* app_ids = default_apps->GetDefaultApps();
   DCHECK(*app_ids == extensions_service_->GetAppIds());
@@ -284,6 +310,19 @@ void AppLauncherHandler::HandleHideAppsPromo(const ListValue* args) {
   extensions_service_->default_apps()->SetPromoHidden();
 }
 
+// static
+bool AppLauncherHandler::HandlePing(const std::string& path) {
+  if (path.find(kLaunchWebStorePingURL) != std::string::npos) {
+    RecordWebStoreLaunch(IsPromoActive(path));
+    return true;
+  } else if (path.find(kLaunchAppPingURL) != std::string::npos) {
+    RecordAppLaunch(IsPromoActive(path));
+    return true;
+  }
+
+  return false;
+}
+
 ExtensionInstallUI* AppLauncherHandler::GetExtensionInstallUI() {
   if (!install_ui_.get())
     install_ui_.reset(new ExtensionInstallUI(dom_ui_->GetProfile()));
@@ -308,3 +347,24 @@ void AppLauncherHandler::InstallUIProceed() {
 void AppLauncherHandler::InstallUIAbort() {
   extension_id_prompting_ = "";
 }
+
+//static
+void AppLauncherHandler::RecordWebStoreLaunch(bool promo_active) {
+  if (!promo_active) return;
+
+  UMA_HISTOGRAM_ENUMERATION(extension_misc::kAppsPromoHistogram,
+                            extension_misc::PROMO_LAUNCH_WEB_STORE,
+                            extension_misc::PROMO_BUCKET_BOUNDARY);
+}
+
+//static
+void AppLauncherHandler::RecordAppLaunch(bool promo_active) {
+  // TODO(jstritar): record app launches that occur when the promo is not
+  // active using a different histogram.
+
+  if (!promo_active) return;
+
+  UMA_HISTOGRAM_ENUMERATION(extension_misc::kAppsPromoHistogram,
+                            extension_misc::PROMO_LAUNCH_APP,
+                            extension_misc::PROMO_BUCKET_BOUNDARY);
+}