Add UpdateCurrentAppInfo() interface to record info about current app, including

chromecast/base/metrics/cast_metrics_helper.cc

Index: chromecast/base/metrics/cast_metrics_helper.cc
diff --git a/chromecast/base/metrics/cast_metrics_helper.cc b/chromecast/base/metrics/cast_metrics_helper.cc
index dda5f51ac82a5218ffe18a111427d1e8d0aa0383..d2d21ad67b29691830022aa009a71048d72236bc 100644
--- a/chromecast/base/metrics/cast_metrics_helper.cc
+++ b/chromecast/base/metrics/cast_metrics_helper.cc
@@ -10,6 +10,8 @@
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/user_metrics.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
 #include "chromecast/base/metrics/cast_histograms.h"
 #include "chromecast/base/metrics/grouped_histogram.h"
 
@@ -38,11 +40,39 @@ const int kNominalVideoSamplePeriod = 5000000;
 
 }  // namespace
 
+// static
+const char CastMetricsHelper::kMetricsNameAppInfoDelimiter = '#';
+
+// static
+CastMetricsHelper::MetricsAppInfo CastMetricsHelper::GetAppInfoFromMetricsName(
+    const std::string& metrics_name) {
+  // TODO(gfhuang): This is a hacky way to encode/decode app infos into a

[gunsch, 2014/12/10 22:43:58]

Got a planned approach for the TODO, or is this just an FYI?

[gfhuang, 2014/12/11 02:59:39]

Change to a NOTE.

+  // string. Mainly because it's hard to add another metrics serialization type
+  // into components/metrics/serialization/.
+  std::vector<std::string> tokens;
+  base::SplitString(metrics_name, kMetricsNameAppInfoDelimiter, &tokens);
+  DCHECK_EQ(tokens.size(), 4u);
+  CastMetricsHelper::MetricsAppInfo metrics_app_info;
+  // The order of tokens should match GetMetricsNameWithAppInfo().
+  metrics_app_info.action_name = tokens[0];
+  metrics_app_info.app_id = tokens[1];
+  metrics_app_info.session_id = tokens[2];
+  metrics_app_info.sdk_version = tokens[3];
+  return metrics_app_info;
+}
+
+// static
 CastMetricsHelper* CastMetricsHelper::GetInstance() {
   DCHECK(g_instance);
   return g_instance;
 }
 
+CastMetricsHelper::MetricsAppInfo::MetricsAppInfo() {
+}
+
+CastMetricsHelper::MetricsAppInfo::~MetricsAppInfo() {
+}
+
 CastMetricsHelper::CastMetricsHelper(
     scoped_refptr<base::MessageLoopProxy> message_loop_proxy)
     : message_loop_proxy_(message_loop_proxy),
@@ -71,14 +101,24 @@ void CastMetricsHelper::TagAppStart(const std::string& arg_app_name) {
   new_startup_time_ = true;
 
   TagAppStartForGroupedHistograms(app_name_);
+  // Clear app info
+  UpdateCurrentAppInfo("", "", "");
 }
 
+void CastMetricsHelper::UpdateCurrentAppInfo(const std::string& app_id,
+                                             const std::string& session_id,
+                                             const std::string& sdk_version) {
+  MAKE_SURE_THREAD(UpdateCurrentAppInfo, app_id, session_id, sdk_version);
+  app_id_ = app_id;
+  session_id_ = session_id;
+  sdk_version_ = sdk_version;
+}

[gunsch, 2014/12/10 22:43:58]

style nit: blank line between methods

[gfhuang, 2014/12/11 02:59:39]

Done.

 void CastMetricsHelper::LogMediaPlay() {
-  RecordSimpleAction(GetMetricsNameWithAppName("MediaPlay", ""));
+  RecordSimpleAction(GetMetricsNameWithAppInfo("MediaPlay"));
 }
 
 void CastMetricsHelper::LogMediaPause() {
-  RecordSimpleAction(GetMetricsNameWithAppName("MediaPause", ""));
+  RecordSimpleAction(GetMetricsNameWithAppInfo("MediaPause"));
 }
 
 void CastMetricsHelper::LogTimeToDisplayVideo() {
@@ -189,6 +229,17 @@ std::string CastMetricsHelper::GetMetricsNameWithAppName(
   return metrics_name;
 }
 
+std::string CastMetricsHelper::GetMetricsNameWithAppInfo(
+    const std::string& action_name) const {
+  DCHECK(message_loop_proxy_->BelongsToCurrentThread());
+  std::vector<std::string> parts;
+  parts.push_back(action_name);
+  parts.push_back(app_id_);
+  parts.push_back(session_id_);
+  parts.push_back(sdk_version_);
+  return JoinString(parts, kMetricsNameAppInfoDelimiter);
+}
+
 void CastMetricsHelper::SetMetricsSink(MetricsSink* delegate) {
   MAKE_SURE_THREAD(SetMetricsSink, delegate);
   metrics_sink_ = delegate;