// Copyright 2014 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_DOMAIN_RELIABILITY_SCHEDULER_H_ #define COMPONENTS_DOMAIN_RELIABILITY_SCHEDULER_H_ #include <vector> #include "base/callback.h" #include "base/time/time.h" #include "components/domain_reliability/domain_reliability_export.h" namespace domain_reliability { class DomainReliabilityConfig; class MockableTime; // Determines when an upload should be scheduled. A domain's config will // specify minimum and maximum upload delays; the minimum upload delay ensures // that Chrome will not send too many upload requests to a site by waiting at // least that long after the first beacon, while the maximum upload delay makes // sure the server receives the reports while they are still fresh. // // When everything is working fine, the scheduler will return precisely that // interval. If all uploaders have failed, then the beginning or ending points // of the interval may be pushed later to accomodate the retry with exponential // backoff. // // See dispatcher.h for an explanation of what happens with the scheduled // interval. class DOMAIN_RELIABILITY_EXPORT DomainReliabilityScheduler { public: typedef base::Callback<void(base::TimeDelta, base::TimeDelta)> ScheduleUploadCallback; struct Params { public: base::TimeDelta minimum_upload_delay; base::TimeDelta maximum_upload_delay; base::TimeDelta upload_retry_interval; static Params GetFromFieldTrialsOrDefaults(); }; DomainReliabilityScheduler(MockableTime* time, size_t num_collectors, const Params& params, const ScheduleUploadCallback& callback); ~DomainReliabilityScheduler(); // Called when a beacon is added to the context. May call the provided // ScheduleUploadCallback (if all previous beacons have been uploaded). void OnBeaconAdded(); // Called when an upload is about to start. void OnUploadStart(int* collector_index_out); // Called when an upload has finished. May call the provided // ScheduleUploadCallback (if the upload failed, or if beacons arrived // during the upload). void OnUploadComplete(bool success); private: struct CollectorState { CollectorState(); // The number of consecutive failures to upload to this collector, or 0 if // the most recent upload succeeded. int failures; base::TimeTicks next_upload; }; void MaybeScheduleUpload(); void GetNextUploadTimeAndCollector(base::TimeTicks now, base::TimeTicks* upload_time_out, int* collector_index_out); base::TimeDelta GetUploadRetryInterval(int failures); MockableTime* time_; std::vector<CollectorState> collectors_; Params params_; ScheduleUploadCallback callback_; // Whether there are beacons that have not yet been uploaded. Set when a // beacon arrives or an upload fails, and cleared when an upload starts. bool upload_pending_; // Whether the scheduler has called the ScheduleUploadCallback to schedule // the next upload. Set when an upload is scheduled and cleared when the // upload starts. bool upload_scheduled_; // Whether the last scheduled upload is in progress. Set when the upload // starts and cleared when the upload completes (successfully or not). bool upload_running_; // Index of the collector selected for the next upload. (Set in // |OnUploadStart| and cleared in |OnUploadComplete|.) int collector_index_; // Time of the first beacon that was not included in the last successful // upload. base::TimeTicks first_beacon_time_; // first_beacon_time_ saved during uploads. Restored if upload fails. base::TimeTicks old_first_beacon_time_; }; } // namespace domain_reliability #endif // COMPONENTS_DOMAIN_RELIABILITY_SCHEDULER_H_