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Diffstat (limited to 'components/rappor/rappor_service.cc')
| -rw-r--r-- | components/rappor/rappor_service.cc | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/components/rappor/rappor_service.cc b/components/rappor/rappor_service.cc new file mode 100644 index 0000000..493e7b9 --- /dev/null +++ b/components/rappor/rappor_service.cc @@ -0,0 +1,187 @@ +// Copyright 2014 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 "components/rappor/rappor_service.h" + +#include "base/base64.h" +#include "base/metrics/field_trial.h" +#include "base/prefs/pref_registry_simple.h" +#include "base/prefs/pref_service.h" +#include "base/rand_util.h" +#include "base/stl_util.h" +#include "components/metrics/metrics_hashes.h" +#include "components/rappor/proto/rappor_metric.pb.h" +#include "components/rappor/rappor_pref_names.h" +#include "components/variations/variations_associated_data.h" + +namespace rappor { + +namespace { + +// The number of cohorts we divide clients into. +const int kNumCohorts = 32; + +// Seconds before the initial log is generated. +const int kInitialLogIntervalSeconds = 15; +// Interval between ongoing logs. +const int kLogIntervalSeconds = 30 * 60; + +const char kMimeType[] = "application/vnd.chrome.rappor"; + +// Constants for the RAPPOR rollout field trial. +const char kRapporRolloutFieldTrialName[] = "RapporRollout"; + +// Constant for the finch parameter name for the server URL +const char kRapporRolloutServerUrlParam[] = "ServerUrl"; + +GURL GetServerUrl() { + return GURL(chrome_variations::GetVariationParamValue( + kRapporRolloutFieldTrialName, + kRapporRolloutServerUrlParam)); +} + +const RapporParameters kRapporParametersForType[NUM_RAPPOR_TYPES] = { + { // ETLD_PLUS_ONE_RAPPOR_TYPE + 16 /* Bloom filter size bytes */, + 2 /* Bloom filter hash count */, + rappor::PROBABILITY_75 /* Fake data probability */, + rappor::PROBABILITY_50 /* Fake one probability */, + rappor::PROBABILITY_75 /* One coin probability */, + rappor::PROBABILITY_50 /* Zero coin probability */ + }, +}; + +} // namespace + +RapporService::RapporService() : cohort_(-1) {} + +RapporService::~RapporService() { + STLDeleteValues(&metrics_map_); +} + +void RapporService::Start(PrefService* pref_service, + net::URLRequestContextGetter* request_context) { + GURL server_url = GetServerUrl(); + if (!server_url.is_valid()) + return; + DCHECK(!uploader_); + LoadSecret(pref_service); + LoadCohort(pref_service); + uploader_.reset(new LogUploader(server_url, kMimeType, request_context)); + log_rotation_timer_.Start( + FROM_HERE, + base::TimeDelta::FromSeconds(kInitialLogIntervalSeconds), + this, + &RapporService::OnLogInterval); +} + +void RapporService::OnLogInterval() { + DCHECK(uploader_); + RapporReports reports; + if (ExportMetrics(&reports)) { + std::string log_text; + bool success = reports.SerializeToString(&log_text); + DCHECK(success); + uploader_->QueueLog(log_text); + } + log_rotation_timer_.Start(FROM_HERE, + base::TimeDelta::FromSeconds(kLogIntervalSeconds), + this, + &RapporService::OnLogInterval); +} + +// static +void RapporService::RegisterPrefs(PrefRegistrySimple* registry) { + registry->RegisterStringPref(prefs::kRapporSecret, std::string()); + registry->RegisterIntegerPref(prefs::kRapporCohort, -1); +} + +void RapporService::LoadCohort(PrefService* pref_service) { + DCHECK_EQ(cohort_, -1); + cohort_ = pref_service->GetInteger(prefs::kRapporCohort); + if (cohort_ >= 0 && cohort_ < kNumCohorts) + return; + + cohort_ = base::RandGenerator(kNumCohorts); + pref_service->SetInteger(prefs::kRapporCohort, cohort_); +} + +void RapporService::LoadSecret(PrefService* pref_service) { + DCHECK(secret_.empty()); + std::string secret_base64 = + pref_service->GetString(prefs::kRapporSecret); + if (!secret_base64.empty()) { + bool decoded = base::Base64Decode(secret_base64, &secret_); + if (decoded && secret_.size() == HmacByteVectorGenerator::kEntropyInputSize) + return; + // If the preference fails to decode, or is the wrong size, it must be + // corrupt, so continue as though it didn't exist yet and generate a new + // one. + } + + secret_ = HmacByteVectorGenerator::GenerateEntropyInput(); + base::Base64Encode(secret_, &secret_base64); + pref_service->SetString(prefs::kRapporSecret, secret_base64); +} + +bool RapporService::ExportMetrics(RapporReports* reports) { + if (metrics_map_.empty()) + return false; + + DCHECK_GE(cohort_, 0); + reports->set_cohort(cohort_); + + for (std::map<std::string, RapporMetric*>::iterator it = metrics_map_.begin(); + metrics_map_.end() != it; + ++it) { + const RapporMetric* metric = it->second; + RapporReports::Report* report = reports->add_report(); + report->set_name_hash(metrics::HashMetricName(it->first)); + ByteVector bytes = metric->GetReport(secret_); + report->set_bits(std::string(bytes.begin(), bytes.end())); + } + STLDeleteValues(&metrics_map_); + return true; +} + +bool RapporService::IsInitialized() const { + return cohort_ >= 0; +} + +void RapporService::RecordSample(const std::string& metric_name, + RapporType type, + const std::string& sample) { + // Ignore the sample if the service hasn't started yet. + if (!IsInitialized()) + return; + DCHECK_LT(type, NUM_RAPPOR_TYPES); + RecordSampleInternal(metric_name, kRapporParametersForType[type], sample); +} + +void RapporService::RecordSampleInternal(const std::string& metric_name, + const RapporParameters& parameters, + const std::string& sample) { + DCHECK(IsInitialized()); + + RapporMetric* metric = LookUpMetric(metric_name, parameters); + metric->AddSample(sample); +} + +RapporMetric* RapporService::LookUpMetric(const std::string& metric_name, + const RapporParameters& parameters) { + DCHECK(IsInitialized()); + std::map<std::string, RapporMetric*>::iterator it = + metrics_map_.find(metric_name); + if (metrics_map_.end() != it) { + RapporMetric* metric = it->second; + DCHECK_EQ(parameters.ToString(), metric->parameters().ToString()); + return metric; + } + + RapporMetric* new_metric = new RapporMetric(metric_name, parameters, cohort_); + metrics_map_[metric_name] = new_metric; + return new_metric; +} + +} // namespace rappor |