| // 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 "chrome/installer/util/experiment.h" |
| |
| #include <algorithm> |
| #include <cmath> |
| |
| #include "base/logging.h" |
| |
| namespace installer { |
| |
| namespace { |
| |
| // Returns closest integer of logarithm of |x| with base |b|. |
| double LogFloor(double x, double b) { |
| return std::round(std::log(x) / std::log(b)); |
| } |
| |
| // Returns the base to use for exponential buckets so that buckets |
| // 0,1,.. 2^|bits|-1 cover range [0, max_val]. If this function return b |
| // then Bucket value i will store values from [b^i, b^(i+1)] |
| double ExpBucketBase(int max_val, int bits) { |
| return std::exp(std::log(max_val + 1) / ((1 << bits) - 1)); |
| } |
| |
| } // namespace |
| |
| Experiment::Experiment() = default; |
| Experiment::Experiment(Experiment&&) = default; |
| Experiment::Experiment(const Experiment&) = default; |
| Experiment::~Experiment() = default; |
| |
| void Experiment::InitializeFromMetrics(const ExperimentMetrics& metrics) { |
| *this = Experiment(); |
| DCHECK(metrics.InInitialState() || |
| metrics.state == ExperimentMetrics::kGroupAssigned); |
| metrics_ = metrics; |
| state_ = metrics.state; |
| group_ = metrics.group; |
| if (metrics.state == ExperimentMetrics::kUninitialized) { |
| // Reset any value stored in experiment. |
| toast_location_ = ExperimentMetrics::kOverTaskbarPin; |
| inactive_days_ = 0; |
| toast_count_ = 0; |
| first_display_time_ = base::Time(); |
| latest_display_time_ = base::Time(); |
| user_session_uptime_ = base::TimeDelta(); |
| action_delay_ = base::TimeDelta(); |
| } |
| } |
| |
| void Experiment::SetState(ExperimentMetrics::State state) { |
| DCHECK_NE(ExperimentMetrics::kUninitialized, state); |
| state_ = state; |
| metrics_.state = state; |
| } |
| |
| void Experiment::AssignGroup(int group) { |
| DCHECK_GE(group, 0); |
| DCHECK_LT(group, ExperimentMetrics::kNumGroups); |
| DCHECK(metrics_.InInitialState()); |
| |
| group_ = group; |
| metrics_.group = group; |
| SetState(ExperimentMetrics::kGroupAssigned); |
| } |
| |
| void Experiment::SetToastLocation(ExperimentMetrics::ToastLocation location) { |
| DCHECK(!metrics_.InTerminalState()); |
| DCHECK(!metrics_.InInitialState()); |
| toast_location_ = location; |
| metrics_.toast_location = location; |
| } |
| |
| void Experiment::SetInactiveDays(int days) { |
| DCHECK(!metrics_.InTerminalState()); |
| DCHECK(!metrics_.InInitialState()); |
| DCHECK_GE(days, 0); |
| inactive_days_ = days; |
| double log_base = ExpBucketBase(ExperimentMetrics::kMaxLastUsed, |
| ExperimentMetrics::kLastUsedBucketBits); |
| metrics_.last_used_bucket = LogFloor( |
| 1 + std::min(days, static_cast<int>(ExperimentMetrics::kMaxLastUsed)), |
| log_base); |
| } |
| |
| void Experiment::SetToastCount(int count) { |
| DCHECK(!metrics_.InTerminalState()); |
| DCHECK(!metrics_.InInitialState()); |
| toast_count_ = count; |
| metrics_.toast_count = |
| std::min(count, static_cast<int>(ExperimentMetrics::kMaxToastCount)); |
| } |
| |
| void Experiment::SetDisplayTime(base::Time time) { |
| DCHECK(!metrics_.InTerminalState()); |
| DCHECK(!metrics_.InInitialState()); |
| if (metrics_.first_toast_offset_days == 0) { |
| // This is the first time toast is shown so add user to today's cohort. |
| first_display_time_ = time; |
| metrics_.first_toast_offset_days = |
| (time - base::Time::UnixEpoch() - |
| base::TimeDelta::FromSeconds( |
| ExperimentMetrics::kExperimentStartSeconds)) |
| .InDays(); |
| // If display time is outside the experiment range (possible due to |
| // invalid local time), then set it to be kMaxFirstToastOffsetDays. |
| if (metrics_.first_toast_offset_days < 0) { |
| metrics_.first_toast_offset_days = |
| ExperimentMetrics::kMaxFirstToastOffsetDays; |
| } else { |
| metrics_.first_toast_offset_days = std::min( |
| metrics_.first_toast_offset_days, |
| static_cast<int>(ExperimentMetrics::kMaxFirstToastOffsetDays)); |
| } |
| } |
| latest_display_time_ = time; |
| metrics_.toast_hour = (time - time.LocalMidnight()).InHours(); |
| DCHECK_LE(metrics_.toast_hour, 24); |
| DCHECK_GE(metrics_.toast_hour, 0); |
| } |
| |
| void Experiment::SetUserSessionUptime(base::TimeDelta time_delta) { |
| DCHECK(!metrics_.InTerminalState()); |
| DCHECK(!metrics_.InInitialState()); |
| user_session_uptime_ = time_delta; |
| double log_base = ExpBucketBase(ExperimentMetrics::kMaxSessionLength, |
| ExperimentMetrics::kSessionLengthBucketBits); |
| if (time_delta.InMinutes() < 0 || |
| time_delta.InMinutes() > ExperimentMetrics::kMaxSessionLength) { |
| time_delta = base::TimeDelta::FromMinutes( |
| ExperimentMetrics::ExperimentMetrics::kMaxSessionLength); |
| } |
| metrics_.session_length_bucket = |
| LogFloor(1 + time_delta.InMinutes(), log_base); |
| } |
| |
| void Experiment::SetActionDelay(base::TimeDelta time_delta) { |
| DCHECK(!metrics_.InTerminalState()); |
| DCHECK(!metrics_.InInitialState()); |
| action_delay_ = time_delta; |
| if (time_delta.InSeconds() < 0 || |
| time_delta.InSeconds() > ExperimentMetrics::kMaxActionDelay) { |
| time_delta = |
| base::TimeDelta::FromSeconds(ExperimentMetrics::kMaxActionDelay); |
| } |
| double log_base = ExpBucketBase(ExperimentMetrics::kMaxActionDelay, |
| ExperimentMetrics::kActionDelayBucketBits); |
| metrics_.action_delay_bucket = LogFloor(1 + time_delta.InSeconds(), log_base); |
| } |
| |
| } // namespace installer |