Support needed to measure user and service traffic in Chrome.

components/data_use_measurement/content/data_use_measurement.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 COMPONENTS_DATA_USE_MEASUREMENT_CONTENT_DATA_USE_MEASUREMENT_H_
+#define COMPONENTS_DATA_USE_MEASUREMENT_CONTENT_DATA_USE_MEASUREMENT_H_
+
+#include <stdint.h>
+#include <string>

[mmenke, 2015/08/31 17:41:29]

Blank line needed between C++ and C headers.

[amohammadkhan, 2015/09/01 04:52:48]

Done.

+
+#include "base/memory/scoped_ptr.h"
+#include "build/build_config.h"
+#include "components/data_use_measurement/core/data_use_user_data.h"
+
+#if defined(OS_ANDROID)
+#include "base/android/application_status_listener.h"
+#endif
+
+namespace net {
+class URLRequest;
+}
+
+namespace data_use_measurement {
+
+class DataUseMeasurement {

[Alexei Svitkine (slow), 2015/08/31 17:26:31]

Class should have a comment.

[mmenke, 2015/08/31 17:41:29]

Need class level docs.

[amohammadkhan, 2015/09/01 04:52:48]

Done.

[amohammadkhan, 2015/09/01 04:52:49]

Done.

+ public:
+  // If the OS is Android, this constructor instantiate a listener object and
+  // bind its callback.

[Alexei Svitkine (slow), 2015/08/31 17:26:31]

This comment is not useful.

First, it seems it's describing implementation detail. But second, it doesn't
even describe it very well - what kind of listener object - what's the callback
- why is it doing it, etc.

[amohammadkhan, 2015/09/01 04:52:48]

Done.

+  DataUseMeasurement();
+
+  ~DataUseMeasurement();
+
+  // Records the data use of the |request|.
+  void ReportDataUseUMA(const net::URLRequest* request);
+
+#if defined(OS_ANDROID)
+  // If a change in application status happens, this function is called and this
+  // function sets app_state_ appropriately.
+  void OnApplicationStateChange(
+      base::android::ApplicationState application_state);

[mmenke, 2015/08/31 17:41:29]

If this is only public for tests, I suggest making it a private method, and then
making a public method called OnApplicationStateChangeForTesting /
OnApplicationStateChangeFors, which calls it.  That makes it clearer it's not
part of the public API.

[amohammadkhan, 2015/09/01 04:52:48]

Done.

+#endif

[Alexei Svitkine (slow), 2015/08/31 17:26:31]

Add an empty line after this.

[amohammadkhan, 2015/09/01 04:52:48]

Done.

+ private:
+  // Specifies that data is received or sent, respectively.
+  enum TrafficDirection { DOWNLOAD, UPLOAD };
+
+  // The state of the application. Only available on Android and on other
+  // platforms it is always FOREGROUND.
+  enum AppState { BACKGROUND, FOREGROUND };
+
+  // The type of network connection that was used.
+  enum ConnectionType { CELLULAR, NOT_CELLULAR };
+
+  // The reason a request was sent. Whether the traffic originates from
+  // user's request for a web site or a service is the source of the traffic.
+  enum ChromeTrafficType { USER_TRAFFIC, SERVICE_TRAFFIC };
+
+  // Returns the current application state (Foreground or Background). It always
+  // returns Foreground if Chrome is not running on Android.
+  AppState CurrentAppState();
+
+  // Returns the current connection type (Cellular or Not cellular).
+  ConnectionType CurrentConnectionType();
+
+  // The function produces a string representing the status of the Chrome when
+  // recording is done. Its output is in following form: dir.appState.ConnState
+  // for example: Upload.Foreground.Cellular is one of its possible outputs.
+  std::string GetDimensionForHistogramName(TrafficDirection dir);
+
+  // Helper function used to record data use of services.
+  void ReportDataUsage(
+      data_use_measurement::DataUseUserData::ServiceType service,
+      TrafficDirection dir,
+      int64_t message_size);
+
+  // Helper function used for reporting data use of URLRequests.
+  void ReportDataUsageURLRequest(ChromeTrafficType service_type,
+                                 TrafficDirection dir,
+                                 int64_t message_size);
+
+#if defined(OS_ANDROID)
+  // Application listener store the last known state of the application in this
+  // field.
+  base::android::ApplicationState app_state_;
+
+  // ApplicationStatusListener used to monitor that application is in foreground
+  // or in background. It is owned by DataUseMeasurement
+  scoped_ptr<base::android::ApplicationStatusListener> app_listener_;
+#endif
+};

[Alexei Svitkine (slow), 2015/08/31 17:26:31]

DISALLOW_COPY_AND_ASSIGN

[amohammadkhan, 2015/09/01 04:52:49]

Done.

+
+}  // namespace data_use_measurement
+#endif  // COMPONENTS_DATA_USE_MEASUREMENT_CONTENT_DATA_USE_MEASUREMENT_H_