1// Copyright 2014 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef BASE_METRICS_USER_METRICS_H_ 6#define BASE_METRICS_USER_METRICS_H_ 7 8#include <string> 9 10#include "base/base_export.h" 11#include "base/callback.h" 12#include "base/metrics/user_metrics_action.h" 13 14namespace base { 15 16// This module provides some helper functions for logging actions tracked by 17// the user metrics system. 18 19// Record that the user performed an action. 20// This method *must* be called from the main thread. 21// 22// "Action" here means a user-generated event: 23// good: "Reload", "CloseTab", and "IMEInvoked" 24// not good: "SSLDialogShown", "PageLoaded", "DiskFull" 25// We use this to gather anonymized information about how users are 26// interacting with the browser. 27// WARNING: In calls to this function, UserMetricsAction and a 28// string literal parameter must be on the same line, e.g. 29// RecordAction(UserMetricsAction("my extremely long action name")); 30// This ensures that our processing scripts can associate this action's hash 31// with its metric name. Therefore, it will be possible to retrieve the metric 32// name from the hash later on. 33// 34// Once a new recorded action is added, run 35// tools/metrics/actions/extract_actions.py 36// to add the metric to actions.xml, then update the <owner>s and <description> 37// sections. Make sure to include the actions.xml file when you upload your code 38// for review! 39// 40// For more complicated situations (like when there are many different 41// possible actions), see RecordComputedAction. 42BASE_EXPORT void RecordAction(const UserMetricsAction& action); 43 44// This function has identical input and behavior to RecordAction, but is 45// not automatically found by the action-processing scripts. It can be used 46// when it's a pain to enumerate all possible actions, but if you use this 47// you need to also update the rules for extracting known actions in 48// tools/metrics/actions/extract_actions.py. 49BASE_EXPORT void RecordComputedAction(const std::string& action); 50 51// Called with the action string. 52typedef base::Callback<void(const std::string&)> ActionCallback; 53 54// Add/remove action callbacks (see above). 55BASE_EXPORT void AddActionCallback(const ActionCallback& callback); 56BASE_EXPORT void RemoveActionCallback(const ActionCallback& callback); 57 58} // namespace base 59 60#endif // BASE_METRICS_USER_METRICS_H_ 61