field_trials_registry.h (1828B)
1 /* 2 * Copyright 2022 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 #ifndef API_FIELD_TRIALS_REGISTRY_H_ 11 #define API_FIELD_TRIALS_REGISTRY_H_ 12 13 #include <string> 14 #include <utility> 15 16 #include "absl/strings/string_view.h" 17 #include "api/field_trials_view.h" 18 #include "rtc_base/containers/flat_set.h" 19 #include "rtc_base/system/rtc_export.h" 20 21 namespace webrtc { 22 23 // Abstract base class for a field trial registry that verifies that any looked 24 // up key has been pre-registered in accordance with `g3doc/field-trials.md`. 25 class RTC_EXPORT FieldTrialsRegistry : public FieldTrialsView { 26 public: 27 FieldTrialsRegistry() = default; 28 29 FieldTrialsRegistry(const FieldTrialsRegistry&) = default; 30 FieldTrialsRegistry& operator=(const FieldTrialsRegistry&) = default; 31 32 ~FieldTrialsRegistry() override = default; 33 34 // Verifies that `key` is a registered field trial and then returns the 35 // configured value for `key` or an empty string if the field trial isn't 36 // configured. 37 std::string Lookup(absl::string_view key) const override; 38 39 // Register additional `keys` for testing. This should only be used for 40 // imaginary keys that are never used outside test code. 41 void RegisterKeysForTesting(flat_set<std::string> keys) { 42 test_keys_ = std::move(keys); 43 } 44 45 private: 46 virtual std::string GetValue(absl::string_view key) const = 0; 47 48 // Imaginary keys only used for testing. 49 flat_set<std::string> test_keys_; 50 }; 51 52 } // namespace webrtc 53 54 #endif // API_FIELD_TRIALS_REGISTRY_H_