blob: fda24aee9338b8201e98a3478e31aaacd34dad96 [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 <memory>
#include <string>
#include "base/lazy_instance.h"
#include "base/macros.h"
#include "base/metrics/field_trial.h"
#include "base/sequence_checker.h"
#include "components/metrics/enabled_state_provider.h"
#include "components/metrics/metrics_log_uploader.h"
#include "components/metrics/metrics_service_client.h"
class PrefService;
namespace metrics {
class MetricsStateManager;
namespace android_webview {
// AwMetricsServiceClient is a singleton which manages WebView metrics
// collection.
// Metrics should be enabled iff all these conditions are met:
// - The user has not opted out (controlled by GMS).
// - The app has not opted out (controlled by manifest tag).
// - This client is in the 2% sample (controlled by client ID hash).
// The first two are recorded in |user_and_app_consent_|, which is set by
// SetHaveMetricsConsent(). The last is recorded in |is_in_sample_|.
// Metrics are pseudonymously identified by a randomly-generated "client ID".
// WebView stores this in prefs, written to the app's data directory. There's a
// different such directory for each user, for each app, on each device. So the
// ID should be unique per (device, app, user) tuple.
// To avoid the appearance that we're doing anything sneaky, the client ID
// should only be created and retained when neither the user nor the app have
// opted out. Otherwise, the presence of the ID could give the impression that
// metrics were being collected.
// WebView metrics set up happens like so:
// startup
// │
// ├────────────┐
// │ ▼
// │ query GMS for consent
// ▼ │
// Initialize() │
// │ ▼
// │ SetHaveMetricsConsent()
// │ │
// │ ┌──────────┘
// ▼ ▼
// MaybeStartMetrics()
// │
// ▼
// MetricsService::Start()
// All the named functions in this diagram happen on the UI thread. Querying GMS
// happens in the background, and the result is posted back to the UI thread, to
// SetHaveMetricsConsent(). Querying GMS is slow, so SetHaveMetricsConsent()
// typically happens after Initialize(), but it may happen before.
// Each path sets a flag, |init_finished_| or |set_consent_finished_|, to show
// that path has finished, and then calls MaybeStartMetrics(). When
// MaybeStartMetrics() is called the first time, it sees only one flag is true,
// and does nothing. When MaybeStartMetrics() is called the second time, it
// decides whether to start metrics.
// If consent was granted, MaybeStartMetrics() determines sampling by hashing
// the client ID (generating a new ID if there was none). If this client is in
// the sample, it then calls MetricsService::Start(). If consent was not
// granted, MaybeStartMetrics() instead clears the client ID, if any.
class AwMetricsServiceClient : public metrics::MetricsServiceClient,
public metrics::EnabledStateProvider {
friend struct base::LazyInstanceTraitsBase<AwMetricsServiceClient>;
static AwMetricsServiceClient* GetInstance();
~AwMetricsServiceClient() override;
void Initialize(PrefService* pref_service);
void SetHaveMetricsConsent(bool consent);
std::unique_ptr<const base::FieldTrial::EntropyProvider>
// metrics::EnabledStateProvider
bool IsConsentGiven() const override;
bool IsReportingEnabled() const override;
// metrics::MetricsServiceClient
metrics::MetricsService* GetMetricsService() override;
void SetMetricsClientId(const std::string& client_id) override;
int32_t GetProduct() override;
std::string GetApplicationLocale() override;
bool GetBrand(std::string* brand_code) override;
metrics::SystemProfileProto::Channel GetChannel() override;
std::string GetVersionString() override;
void CollectFinalMetricsForLog(const base::Closure& done_callback) override;
std::unique_ptr<metrics::MetricsLogUploader> CreateUploader(
const GURL& server_url,
const GURL& insecure_server_url,
base::StringPiece mime_type,
metrics::MetricsLogUploader::MetricServiceType service_type,
const metrics::MetricsLogUploader::UploadCallback& on_upload_complete)
base::TimeDelta GetStandardUploadInterval() override;
std::string GetAppPackageName() override;
virtual bool IsInSample(); // virtual for testing
void MaybeStartMetrics();
std::unique_ptr<metrics::MetricsStateManager> metrics_state_manager_;
std::unique_ptr<metrics::MetricsService> metrics_service_;
PrefService* pref_service_ = nullptr;
bool init_finished_ = false;
bool set_consent_finished_ = false;
bool user_and_app_consent_ = false;
bool is_in_sample_ = false;
// AwMetricsServiceClient may be created before the UI thread is promoted to
// BrowserThread::UI. Use |sequence_checker_| to enforce that the
// AwMetricsServiceClient is used on a single thread.
base::SequenceChecker sequence_checker_;
} // namespace android_webview