1 // Copyright 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "components/variations/variations_seed_processor.h"
6
7 #include <vector>
8
9 #include "base/command_line.h"
10 #include "base/metrics/field_trial.h"
11 #include "components/variations/processed_study.h"
12 #include "components/variations/study_filtering.h"
13 #include "components/variations/variations_associated_data.h"
14
15 namespace chrome_variations {
16
17 namespace {
18
19 // Associates the variations params of |experiment|, if present.
RegisterExperimentParams(const Study & study,const Study_Experiment & experiment)20 void RegisterExperimentParams(const Study& study,
21 const Study_Experiment& experiment) {
22 std::map<std::string, std::string> params;
23 for (int i = 0; i < experiment.param_size(); ++i) {
24 if (experiment.param(i).has_name() && experiment.param(i).has_value())
25 params[experiment.param(i).name()] = experiment.param(i).value();
26 }
27 if (!params.empty())
28 AssociateVariationParams(study.name(), experiment.name(), params);
29 }
30
31 // If there are variation ids associated with |experiment|, register the
32 // variation ids.
RegisterVariationIds(const Study_Experiment & experiment,const std::string & trial_name)33 void RegisterVariationIds(const Study_Experiment& experiment,
34 const std::string& trial_name) {
35 if (experiment.has_google_web_experiment_id()) {
36 const VariationID variation_id =
37 static_cast<VariationID>(experiment.google_web_experiment_id());
38 AssociateGoogleVariationIDForce(GOOGLE_WEB_PROPERTIES,
39 trial_name,
40 experiment.name(),
41 variation_id);
42 }
43 if (experiment.has_google_web_trigger_experiment_id()) {
44 const VariationID variation_id =
45 static_cast<VariationID>(experiment.google_web_trigger_experiment_id());
46 AssociateGoogleVariationIDForce(GOOGLE_WEB_PROPERTIES_TRIGGER,
47 trial_name,
48 experiment.name(),
49 variation_id);
50 }
51 if (experiment.has_google_update_experiment_id()) {
52 const VariationID variation_id =
53 static_cast<VariationID>(experiment.google_update_experiment_id());
54 AssociateGoogleVariationIDForce(GOOGLE_UPDATE_SERVICE,
55 trial_name,
56 experiment.name(),
57 variation_id);
58 }
59 }
60
61 } // namespace
62
VariationsSeedProcessor()63 VariationsSeedProcessor::VariationsSeedProcessor() {
64 }
65
~VariationsSeedProcessor()66 VariationsSeedProcessor::~VariationsSeedProcessor() {
67 }
68
CreateTrialsFromSeed(const VariationsSeed & seed,const std::string & locale,const base::Time & reference_date,const base::Version & version,Study_Channel channel,Study_FormFactor form_factor,const std::string & hardware_class)69 void VariationsSeedProcessor::CreateTrialsFromSeed(
70 const VariationsSeed& seed,
71 const std::string& locale,
72 const base::Time& reference_date,
73 const base::Version& version,
74 Study_Channel channel,
75 Study_FormFactor form_factor,
76 const std::string& hardware_class) {
77 std::vector<ProcessedStudy> filtered_studies;
78 FilterAndValidateStudies(seed, locale, reference_date, version, channel,
79 form_factor, hardware_class, &filtered_studies);
80
81 for (size_t i = 0; i < filtered_studies.size(); ++i)
82 CreateTrialFromStudy(filtered_studies[i]);
83 }
84
CreateTrialFromStudy(const ProcessedStudy & processed_study)85 void VariationsSeedProcessor::CreateTrialFromStudy(
86 const ProcessedStudy& processed_study) {
87 const Study& study = *processed_study.study();
88
89 // Check if any experiments need to be forced due to a command line
90 // flag. Force the first experiment with an existing flag.
91 CommandLine* command_line = CommandLine::ForCurrentProcess();
92 for (int i = 0; i < study.experiment_size(); ++i) {
93 const Study_Experiment& experiment = study.experiment(i);
94 if (experiment.has_forcing_flag() &&
95 command_line->HasSwitch(experiment.forcing_flag())) {
96 scoped_refptr<base::FieldTrial> trial(
97 base::FieldTrialList::CreateFieldTrial(study.name(),
98 experiment.name()));
99 RegisterExperimentParams(study, experiment);
100 RegisterVariationIds(experiment, study.name());
101 if (study.activation_type() == Study_ActivationType_ACTIVATION_AUTO)
102 trial->group();
103
104 DVLOG(1) << "Trial " << study.name() << " forced by flag: "
105 << experiment.forcing_flag();
106 return;
107 }
108 }
109
110 uint32 randomization_seed = 0;
111 base::FieldTrial::RandomizationType randomization_type =
112 base::FieldTrial::SESSION_RANDOMIZED;
113 if (study.has_consistency() &&
114 study.consistency() == Study_Consistency_PERMANENT) {
115 randomization_type = base::FieldTrial::ONE_TIME_RANDOMIZED;
116 if (study.has_randomization_seed())
117 randomization_seed = study.randomization_seed();
118 }
119
120 // The trial is created without specifying an expiration date because the
121 // expiration check in field_trial.cc is based on the build date. Instead,
122 // the expiration check using |reference_date| is done explicitly below.
123 scoped_refptr<base::FieldTrial> trial(
124 base::FieldTrialList::FactoryGetFieldTrialWithRandomizationSeed(
125 study.name(), processed_study.total_probability(),
126 study.default_experiment_name(),
127 base::FieldTrialList::kNoExpirationYear, 1, 1, randomization_type,
128 randomization_seed, NULL));
129
130 for (int i = 0; i < study.experiment_size(); ++i) {
131 const Study_Experiment& experiment = study.experiment(i);
132 RegisterExperimentParams(study, experiment);
133
134 // Groups with forcing flags have probability 0 and will never be selected.
135 // Therefore, there's no need to add them to the field trial.
136 if (experiment.has_forcing_flag())
137 continue;
138
139 if (experiment.name() != study.default_experiment_name())
140 trial->AppendGroup(experiment.name(), experiment.probability_weight());
141
142 RegisterVariationIds(experiment, study.name());
143 }
144
145 trial->SetForced();
146 if (processed_study.is_expired())
147 trial->Disable();
148 else if (study.activation_type() == Study_ActivationType_ACTIVATION_AUTO)
149 trial->group();
150 }
151
152 } // namespace chrome_variations
153