blob: 4be74affa0595b29b6a6866b5007cded52ede424 [file] [log] [blame]
// Copyright 2017 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.
#include <vector>
#include "base/observer_list.h"
#include "components/variations/synthetic_trials.h"
namespace metrics {
class MetricsServiceAccessor;
} // namespace metrics
namespace variations {
struct ActiveGroupId;
class FieldTrialsProvider;
class FieldTrialsProviderTest;
class SyntheticTrialRegistry {
// Adds an observer to be notified when the synthetic trials list changes.
void AddSyntheticTrialObserver(SyntheticTrialObserver* observer);
// Removes an existing observer of synthetic trials list changes.
void RemoveSyntheticTrialObserver(SyntheticTrialObserver* observer);
friend metrics::MetricsServiceAccessor;
friend FieldTrialsProvider;
friend FieldTrialsProviderTest;
FRIEND_TEST_ALL_PREFIXES(SyntheticTrialRegistryTest, RegisterSyntheticTrial);
FRIEND_TEST_ALL_PREFIXES(VariationsCrashKeysTest, BasicFunctionality);
// Registers a field trial name and group to be used to annotate a UMA report
// with a particular Chrome configuration state. A UMA report will be
// annotated with this trial group if and only if all events in the report
// were created after the trial is registered. Only one group name may be
// registered at a time for a given trial_name. Only the last group name that
// is registered for a given trial name will be recorded. The values passed
// in must not correspond to any real field trial in the code.
// Note: Should not be used to replace trials that were registered with
// RegisterSyntheticMultiGroupFieldTrial().
void RegisterSyntheticFieldTrial(const SyntheticTrialGroup& trial_group);
// Similar to RegisterSyntheticFieldTrial(), but registers a synthetic trial
// that has multiple active groups for a given trial name hash. Any previous
// groups registered for |trial_name_hash| will be replaced.
void RegisterSyntheticMultiGroupFieldTrial(
uint32_t trial_name_hash,
const std::vector<uint32_t>& group_name_hashes);
// Returns a list of synthetic field trials that are older than |time|.
void GetSyntheticFieldTrialsOlderThan(
base::TimeTicks time,
std::vector<ActiveGroupId>* synthetic_trials);
// Notifies observers on a synthetic trial list change.
void NotifySyntheticTrialObservers();
// Field trial groups that map to Chrome configuration states.
std::vector<SyntheticTrialGroup> synthetic_trial_groups_;
// List of observers of |synthetic_trial_groups_| changes.
} // namespace variations