1 // Copyright (c) 2013 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 CHROME_BROWSER_METRICS_VARIATIONS_VARIATIONS_REQUEST_SCHEDULER_H_ 6 #define CHROME_BROWSER_METRICS_VARIATIONS_VARIATIONS_REQUEST_SCHEDULER_H_ 7 8 #include "base/bind.h" 9 #include "base/gtest_prod_util.h" 10 #include "base/time/time.h" 11 #include "base/timer/timer.h" 12 13 class PrefService; 14 15 namespace chrome_variations { 16 17 // A helper class that makes VariationsService requests at the correct times. 18 class VariationsRequestScheduler { 19 public: 20 virtual ~VariationsRequestScheduler(); 21 22 // Starts the task. This can be a repeated event or a one-off. 23 virtual void Start(); 24 25 // Resets the scheduler if it is currently on a timer. 26 virtual void Reset(); 27 28 // Schedules a fetch shortly, for example to re-try the initial request which 29 // may have failed. 30 void ScheduleFetchShortly(); 31 32 // Called when the application has been foregrounded. This may fetch a new 33 // seed. 34 virtual void OnAppEnterForeground(); 35 36 // Factory method for this class. 37 static VariationsRequestScheduler* Create(const base::Closure& task, 38 PrefService* local_state); 39 40 protected: 41 // |task| is the closure to call when the scheduler deems ready. 42 explicit VariationsRequestScheduler(const base::Closure& task); 43 44 // Getter for derived classes. 45 base::Closure task() const; 46 47 private: 48 FRIEND_TEST_ALL_PREFIXES(VariationsRequestSchedulerTest, 49 ScheduleFetchShortly); 50 51 // The task scheduled by this class. 52 base::Closure task_; 53 54 // The timer used to repeatedly ping the server. Keep this as an instance 55 // member so if VariationsRequestScheduler goes out of scope, the timer is 56 // automatically canceled. 57 base::RepeatingTimer<VariationsRequestScheduler> timer_; 58 59 // A one-shot timer used for scheduling out-of-band fetches. 60 base::OneShotTimer<VariationsRequestScheduler> one_shot_timer_; 61 62 DISALLOW_COPY_AND_ASSIGN(VariationsRequestScheduler); 63 }; 64 65 } // namespace chrome_variations 66 67 #endif // CHROME_BROWSER_METRICS_VARIATIONS_VARIATIONS_REQUEST_SCHEDULER_H_ 68