| // |
| // Copyright (c) 2014 The WebRTC project authors. All Rights Reserved. |
| // |
| // Use of this source code is governed by a BSD-style license |
| // that can be found in the LICENSE file in the root of the source |
| // tree. An additional intellectual property rights grant can be found |
| // in the file PATENTS. All contributing project authors may |
| // be found in the AUTHORS file in the root of the source tree. |
| // |
| |
| #ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_FIELD_TRIAL_H_ |
| #define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_FIELD_TRIAL_H_ |
| |
| #include <string> |
| |
| #include "webrtc/common_types.h" |
| |
| // Field trials allow a client of webrtc (such as Chrome) to turn on feature |
| // code in binraries out in the field and gather information with that. |
| // WebRTC field trials are designed to be wired up directly to chrome field |
| // trials and speed up the time developers need to get features out there by |
| // spending less time wiring up APIs to control whether the feature is on/off. |
| // Note, that not every feature is candidate to be controlled by them as it may |
| // require proper negotiation between involved parties (e.g. SDP negotiation). |
| // |
| // E.g.: To experiment with a new method that could lead to a different |
| // trade-off between CPU/bandwidth: |
| // |
| // 1 - Develop the feature with default behaviour off: |
| // |
| // if (FieldTrial::FindFullName("WebRTCExperimenMethod2") == "Enabled") |
| // method2(); |
| // else |
| // method1(); |
| // |
| // 2 - Once the changes are rolled to chrome, the new code path can be executed |
| // by running chrome with --force-fieldtrials=WebRTCExperimentMethod2/Enabled/ |
| // or controled by finch studies. |
| // |
| // 3 - Evaluate the new feature and clean the code paths. |
| // |
| // TODO(andresp): find out how to get bots and unit tests to run with field |
| // trials enabled. |
| |
| namespace webrtc { |
| namespace field_trial { |
| |
| typedef std::string (*FindFullNameMethod)(const std::string&); |
| |
| // Returns the group name chosen for the named trial, or the empty string |
| // if the trial does not exists. |
| // |
| // Note: To keep things tidy append all the trial names with WebRTC. |
| std::string FindFullName(const std::string& name); |
| |
| // WebRTC clients MUST call this method to setup field trials. |
| // Failing to do so will crash the first time code tries to access a field |
| // trial. |
| // |
| // This method must be called before any WebRTC methods. Functions |
| // provided should be thread-safe. |
| WEBRTC_DLLEXPORT void Init(FindFullNameMethod find); |
| |
| } // namespace field_trial |
| } // namespace webrtc |
| |
| #endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_FIELD_TRIAL_H_ |
