components/optimization_guide/hint_cache_unittest.cc - chromium/src.git - Git at Google

 // Copyright 2018 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/optimization_guide/hint_cache.h"

 #include <string>
 #include <vector>

 #include "base/bind.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/test/metrics/histogram_tester.h"
 #include "base/test/task_environment.h"
 #include "components/optimization_guide/optimization_guide_features.h"
 #include "components/optimization_guide/optimization_guide_store.h"
 #include "components/optimization_guide/proto_database_provider_test_base.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "url/gurl.h"

 namespace optimization_guide {
 namespace {

 std::string GetHostDomainOrg(int index) {
   return "host.domain" + base::NumberToString(index) + ".org";
 }

 class HintCacheTest : public ProtoDatabaseProviderTestBase {
  public:
   HintCacheTest() : loaded_hint_(nullptr) {}

   ~HintCacheTest() override {}

   void SetUp() override { ProtoDatabaseProviderTestBase::SetUp(); }

   void TearDown() override {
     ProtoDatabaseProviderTestBase::TearDown();
     DestroyHintCache();
   }

  protected:
   // Creates and initializes the hint cache and optimization guide store and
   // waits for the callback indicating that initialization is complete.
   void CreateAndInitializeHintCache(int memory_cache_size,
                                     bool purge_existing_data = false) {
     auto database_path = temp_dir_.GetPath();
     auto database_task_runner = task_environment_.GetMainThreadTaskRunner();
     hint_cache_ = std::make_unique<HintCache>(
         std::make_unique<OptimizationGuideStore>(
             db_provider_.get(), database_path, database_task_runner),
         memory_cache_size);
     is_store_initialized_ = false;
     hint_cache_->Initialize(purge_existing_data,
                             base::BindOnce(&HintCacheTest::OnStoreInitialized,
                                            base::Unretained(this)));
     while (!is_store_initialized_) {
       RunUntilIdle();
     }
   }

   void DestroyHintCache() {
     hint_cache_.reset();
     loaded_hint_ = nullptr;
     is_store_initialized_ = false;
     are_component_hints_updated_ = false;
     on_load_hint_callback_called_ = false;
     are_fetched_hints_updated_ = false;

     RunUntilIdle();
   }

   HintCache* hint_cache() { return hint_cache_.get(); }

   bool are_fetched_hints_updated() { return are_fetched_hints_updated_; }

   // Updates the cache with |component_data| and waits for callback indicating
   // that the update is complete.
   void UpdateComponentHints(std::unique_ptr<StoreUpdateData> component_data) {
     are_component_hints_updated_ = false;
     hint_cache_->UpdateComponentHints(
         std::move(component_data),
         base::BindOnce(&HintCacheTest::OnUpdateComponentHints,
                        base::Unretained(this)));
     while (!are_component_hints_updated_) {
       RunUntilIdle();
     }
   }

   void UpdateFetchedHintsAndWait(
       std::unique_ptr<proto::GetHintsResponse> get_hints_response,
       base::Time stored_time) {
     are_fetched_hints_updated_ = false;
     hint_cache_->UpdateFetchedHints(
         std::move(get_hints_response), stored_time,
         base::BindOnce(&HintCacheTest::OnHintsUpdated, base::Unretained(this)));

     while (!are_fetched_hints_updated_)
       RunUntilIdle();
   }

   void OnHintsUpdated() { are_fetched_hints_updated_ = true; }

   // Loads hint for the specified host from the cache and waits for callback
   // indicating that loading the hint is complete.
   void LoadHint(const std::string& host) {
     on_load_hint_callback_called_ = false;
     loaded_hint_ = nullptr;
     hint_cache_->LoadHint(host, base::BindOnce(&HintCacheTest::OnLoadHint,
                                                base::Unretained(this)));
     while (!on_load_hint_callback_called_) {
       RunUntilIdle();
     }
   }

   const proto::Hint* GetLoadedHint() const { return loaded_hint_; }

  private:
   void RunUntilIdle() {
     task_environment_.RunUntilIdle();
     base::RunLoop().RunUntilIdle();
   }

   void OnStoreInitialized() { is_store_initialized_ = true; }
   void OnUpdateComponentHints() { are_component_hints_updated_ = true; }
   void OnLoadHint(const proto::Hint* hint) {
     on_load_hint_callback_called_ = true;
     loaded_hint_ = hint;
   }

   base::test::TaskEnvironment task_environment_;

   std::unique_ptr<HintCache> hint_cache_;
   const proto::Hint* loaded_hint_;

   bool is_store_initialized_;
   bool are_component_hints_updated_;
   bool on_load_hint_callback_called_;
   bool are_fetched_hints_updated_;

   DISALLOW_COPY_AND_ASSIGN(HintCacheTest);
 };

 TEST_F(HintCacheTest, ComponentUpdate) {
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Version version("2.0.0");
   std::unique_ptr<StoreUpdateData> update_data =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
   ASSERT_TRUE(update_data);

   proto::Hint hint1;
   hint1.set_key("subdomain.domain.org");
   hint1.set_key_representation(proto::HOST_SUFFIX);
   proto::Hint hint2;
   hint2.set_key("host.domain.org");
   hint2.set_key_representation(proto::HOST_SUFFIX);
   proto::Hint hint3;
   hint3.set_key("otherhost.subdomain.domain.org");
   hint3.set_key_representation(proto::HOST_SUFFIX);

   update_data->MoveHintIntoUpdateData(std::move(hint1));
   update_data->MoveHintIntoUpdateData(std::move(hint2));
   update_data->MoveHintIntoUpdateData(std::move(hint3));

   UpdateComponentHints(std::move(update_data));

   // Not matched
   EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
   EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

   // Matched
   EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
   EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
   EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));
 }

 TEST_F(HintCacheTest, ComponentUpdateWithSameVersionIgnored) {
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Version version("2.0.0");
   std::unique_ptr<StoreUpdateData> update_data =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
   ASSERT_TRUE(update_data);

   UpdateComponentHints(std::move(update_data));

   EXPECT_FALSE(hint_cache()->MaybeCreateUpdateDataForComponentHints(version));
 }

 TEST_F(HintCacheTest, ComponentUpdateWithEarlierVersionIgnored) {
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Version version_1("1.0.0");
   base::Version version_2("2.0.0");

   std::unique_ptr<StoreUpdateData> update_data =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version_2);
   ASSERT_TRUE(update_data);

   UpdateComponentHints(std::move(update_data));

   EXPECT_FALSE(hint_cache()->MaybeCreateUpdateDataForComponentHints(version_1));
 }

 TEST_F(HintCacheTest, ComponentUpdateWithLaterVersionProcessed) {
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Version version_1("1.0.0");
   base::Version version_2("2.0.0");

   std::unique_ptr<StoreUpdateData> update_data_1 =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version_1);
   ASSERT_TRUE(update_data_1);

   proto::Hint hint1;
   hint1.set_key("subdomain.domain.org");
   hint1.set_key_representation(proto::HOST_SUFFIX);
   proto::Hint hint2;
   hint2.set_key("host.domain.org");
   hint2.set_key_representation(proto::HOST_SUFFIX);
   proto::Hint hint3;
   hint3.set_key("otherhost.subdomain.domain.org");
   hint3.set_key_representation(proto::HOST_SUFFIX);

   update_data_1->MoveHintIntoUpdateData(std::move(hint1));
   update_data_1->MoveHintIntoUpdateData(std::move(hint2));
   update_data_1->MoveHintIntoUpdateData(std::move(hint3));

   UpdateComponentHints(std::move(update_data_1));

   // Not matched
   EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
   EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

   // Matched
   EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
   EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
   EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));

   std::unique_ptr<StoreUpdateData> update_data_2 =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version_2);
   ASSERT_TRUE(update_data_2);

   proto::Hint hint4;
   hint4.set_key("subdomain.domain2.org");
   hint4.set_key_representation(proto::HOST_SUFFIX);
   proto::Hint hint5;
   hint5.set_key("host.domain2.org");
   hint5.set_key_representation(proto::HOST_SUFFIX);
   proto::Hint hint6;
   hint6.set_key("otherhost.subdomain.domain2.org");
   hint6.set_key_representation(proto::HOST_SUFFIX);

   update_data_2->MoveHintIntoUpdateData(std::move(hint4));
   update_data_2->MoveHintIntoUpdateData(std::move(hint5));
   update_data_2->MoveHintIntoUpdateData(std::move(hint6));

   UpdateComponentHints(std::move(update_data_2));

   // Not matched
   EXPECT_FALSE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
   EXPECT_FALSE(hint_cache()->HasHint("host.subdomain.domain.org"));
   EXPECT_FALSE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));
   EXPECT_FALSE(hint_cache()->HasHint("domain2.org"));
   EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain2.org"));

   // Matched
   EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain2.org"));
   EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain2.org"));
   EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain2.org"));
 }

 TEST_F(HintCacheTest, ComponentHintsAvailableAfterRestart) {
   for (int i = 0; i < 2; ++i) {
     const int kMemoryCacheSize = 5;
     CreateAndInitializeHintCache(kMemoryCacheSize,
                                  false /*=purge_existing_data*/);

     base::Version version("2.0.0");

     std::unique_ptr<StoreUpdateData> update_data =
         hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
     if (i == 0) {
       ASSERT_TRUE(update_data);

       proto::Hint hint1;
       hint1.set_key("subdomain.domain.org");
       hint1.set_key_representation(proto::HOST_SUFFIX);
       proto::Hint hint2;
       hint2.set_key("host.domain.org");
       hint2.set_key_representation(proto::HOST_SUFFIX);
       proto::Hint hint3;
       hint3.set_key("otherhost.subdomain.domain.org");
       hint3.set_key_representation(proto::HOST_SUFFIX);

       update_data->MoveHintIntoUpdateData(std::move(hint1));
       update_data->MoveHintIntoUpdateData(std::move(hint2));
       update_data->MoveHintIntoUpdateData(std::move(hint3));

       UpdateComponentHints(std::move(update_data));
     } else {
       EXPECT_FALSE(update_data);
     }

     // Not matched
     EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
     EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

     // Matched
     EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
     EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
     EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));

     DestroyHintCache();
   }
 }

 TEST_F(HintCacheTest, ComponentHintsUpdatableAfterRestartWithPurge) {
   for (int i = 0; i < 2; ++i) {
     const int kMemoryCacheSize = 5;
     CreateAndInitializeHintCache(kMemoryCacheSize,
                                  true /*=purge_existing_data*/);

     base::Version version("2.0.0");

     std::unique_ptr<StoreUpdateData> update_data =
         hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
     ASSERT_TRUE(update_data);

     proto::Hint hint1;
     hint1.set_key("subdomain.domain.org");
     hint1.set_key_representation(proto::HOST_SUFFIX);
     proto::Hint hint2;
     hint2.set_key("host.domain.org");
     hint2.set_key_representation(proto::HOST_SUFFIX);
     proto::Hint hint3;
     hint3.set_key("otherhost.subdomain.domain.org");
     hint3.set_key_representation(proto::HOST_SUFFIX);

     update_data->MoveHintIntoUpdateData(std::move(hint1));
     update_data->MoveHintIntoUpdateData(std::move(hint2));
     update_data->MoveHintIntoUpdateData(std::move(hint3));

     UpdateComponentHints(std::move(update_data));

     // Not matched
     EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
     EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

     // Matched
     EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
     EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
     EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));

     DestroyHintCache();
   }
 }

 TEST_F(HintCacheTest, ComponentHintsNotRetainedAfterRestartWithPurge) {
   for (int i = 0; i < 2; ++i) {
     const int kMemoryCacheSize = 5;
     CreateAndInitializeHintCache(kMemoryCacheSize,
                                  true /*=purge_existing_data*/);

     base::Version version("2.0.0");

     std::unique_ptr<StoreUpdateData> update_data =
         hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
     if (i == 0) {
       ASSERT_TRUE(update_data);

       proto::Hint hint1;
       hint1.set_key("subdomain.domain.org");
       hint1.set_key_representation(proto::HOST_SUFFIX);
       proto::Hint hint2;
       hint2.set_key("host.domain.org");
       hint2.set_key_representation(proto::HOST_SUFFIX);
       proto::Hint hint3;
       hint3.set_key("otherhost.subdomain.domain.org");
       hint3.set_key_representation(proto::HOST_SUFFIX);

       update_data->MoveHintIntoUpdateData(std::move(hint1));
       update_data->MoveHintIntoUpdateData(std::move(hint2));
       update_data->MoveHintIntoUpdateData(std::move(hint3));

       UpdateComponentHints(std::move(update_data));
     } else {
       EXPECT_TRUE(update_data);
     }

     // Not matched
     EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
     EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

     // Maybe matched
     bool should_match = (i == 0);
     EXPECT_EQ(hint_cache()->HasHint("otherhost.subdomain.domain.org"),
               should_match);
     EXPECT_EQ(hint_cache()->HasHint("host.subdomain.domain.org"), should_match);
     EXPECT_EQ(hint_cache()->HasHint("subhost.host.subdomain.domain.org"),
               should_match);

     DestroyHintCache();
   }
 }

 TEST_F(HintCacheTest, TestMemoryCacheLeastRecentlyUsedPurge) {
   const int kTestHintCount = 10;
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Version version("1.0.0");
   std::unique_ptr<StoreUpdateData> update_data =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
   ASSERT_TRUE(update_data);

   for (int i = 0; i < kTestHintCount; ++i) {
     proto::Hint hint;
     hint.set_key(GetHostDomainOrg(i));
     hint.set_key_representation(proto::HOST_SUFFIX);
     update_data->MoveHintIntoUpdateData(std::move(hint));
   }

   UpdateComponentHints(std::move(update_data));

   for (int i = kTestHintCount - 1; i >= 0; --i) {
     std::string host = GetHostDomainOrg(i);
     EXPECT_TRUE(hint_cache()->HasHint(host));
     LoadHint(host);
     ASSERT_TRUE(GetLoadedHint());
     EXPECT_EQ(GetLoadedHint()->key(), host);
   }

   for (int i = 0; i < kTestHintCount; ++i) {
     std::string host = GetHostDomainOrg(i);
     if (i < kMemoryCacheSize) {
       ASSERT_TRUE(hint_cache()->GetHintIfLoaded(host));
       EXPECT_EQ(GetHostDomainOrg(i),
                 hint_cache()->GetHintIfLoaded(host)->key());
     } else {
       EXPECT_FALSE(hint_cache()->GetHintIfLoaded(host));
     }
     EXPECT_TRUE(hint_cache()->HasHint(host));
   }
 }

 TEST_F(HintCacheTest, TestHostNotInCache) {
   const int kTestHintCount = 10;
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Version version("1.0.0");
   std::unique_ptr<StoreUpdateData> update_data =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
   ASSERT_TRUE(update_data);

   for (int i = 0; i < kTestHintCount; ++i) {
     proto::Hint hint;
     hint.set_key(GetHostDomainOrg(i));
     hint.set_key_representation(proto::HOST_SUFFIX);
     update_data->MoveHintIntoUpdateData(std::move(hint));
   }

   UpdateComponentHints(std::move(update_data));

   EXPECT_FALSE(hint_cache()->HasHint(GetHostDomainOrg(kTestHintCount)));
 }

 TEST_F(HintCacheTest, TestMemoryCacheLoadCallback) {
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Version version("1.0.0");
   std::unique_ptr<StoreUpdateData> update_data =
       hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
   ASSERT_TRUE(update_data);

   std::string hint_key = "subdomain.domain.org";
   proto::Hint hint;
   hint.set_key(hint_key);
   hint.set_key_representation(proto::HOST_SUFFIX);
   update_data->MoveHintIntoUpdateData(std::move(hint));

   UpdateComponentHints(std::move(update_data));

   EXPECT_FALSE(hint_cache()->GetHintIfLoaded("host.subdomain.domain.org"));
   LoadHint("host.subdomain.domain.org");
   EXPECT_TRUE(hint_cache()->GetHintIfLoaded("host.subdomain.domain.org"));

   EXPECT_TRUE(GetLoadedHint());
   EXPECT_EQ(hint_key, GetLoadedHint()->key());
 }

 TEST_F(HintCacheTest, StoreValidFetchedHints) {
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   // Default update time for empty optimization guide store is base::Time().
   EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), base::Time());

   std::unique_ptr<proto::GetHintsResponse> get_hints_response =
       std::make_unique<proto::GetHintsResponse>();

   proto::Hint* hint = get_hints_response->add_hints();
   hint->set_key_representation(proto::HOST_SUFFIX);
   hint->set_key("host.domain.org");
   proto::PageHint* page_hint = hint->add_page_hints();
   page_hint->set_page_pattern("page pattern");

   base::Time stored_time = base::Time().Now();
   UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
   EXPECT_TRUE(are_fetched_hints_updated());

   // Next update time for hints should be updated.
   EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);
 }

 TEST_F(HintCacheTest, ParseEmptyFetchedHints) {
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   base::Time stored_time = base::Time().Now() + base::TimeDelta().FromDays(1);
   std::unique_ptr<proto::GetHintsResponse> get_hints_response =
       std::make_unique<proto::GetHintsResponse>();

   UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
   // Empty Fetched Hints causes the metadata entry to be updated.
   EXPECT_TRUE(are_fetched_hints_updated());
   EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);
 }

 TEST_F(HintCacheTest, StoreValidFetchedHintsWithServerProvidedExpiryTime) {
   base::HistogramTester histogram_tester;
   const int kMemoryCacheSize = 5;
   const int kFetchedHintExpirationSecs = 60;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   // Default update time for empty optimization guide store is base::Time().
   EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), base::Time());

   std::unique_ptr<proto::GetHintsResponse> get_hints_response =
       std::make_unique<proto::GetHintsResponse>();

   // Set server-provided expiration time.
   get_hints_response->mutable_max_cache_duration()->set_seconds(
       kFetchedHintExpirationSecs);

   proto::Hint* hint = get_hints_response->add_hints();
   hint->set_key_representation(proto::HOST_SUFFIX);
   hint->set_key("host.domain.org");
   proto::PageHint* page_hint = hint->add_page_hints();
   page_hint->set_page_pattern("page pattern");

   base::Time stored_time = base::Time().Now();
   UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
   EXPECT_TRUE(are_fetched_hints_updated());

   // Next update time for hints should be updated.
   EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);

   LoadHint("host.domain.org");
   // HISTOGRAM TEST!
   histogram_tester.ExpectTimeBucketCount(
       "OptimizationGuide.HintCache.FetchedHint.TimeToExpiration",
       base::TimeDelta::FromSeconds(kFetchedHintExpirationSecs), 1);
 }

 TEST_F(HintCacheTest, StoreValidFetchedHintsWithDefaultExpiryTime) {
   base::HistogramTester histogram_tester;
   const int kMemoryCacheSize = 5;
   CreateAndInitializeHintCache(kMemoryCacheSize);

   // Default update time for empty optimization guide store is base::Time().
   EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), base::Time());

   std::unique_ptr<proto::GetHintsResponse> get_hints_response =
       std::make_unique<proto::GetHintsResponse>();

   proto::Hint* hint = get_hints_response->add_hints();
   hint->set_key_representation(proto::HOST_SUFFIX);
   hint->set_key("host.domain.org");
   proto::PageHint* page_hint = hint->add_page_hints();
   page_hint->set_page_pattern("page pattern");

   base::Time stored_time = base::Time().Now();
   UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
   EXPECT_TRUE(are_fetched_hints_updated());

   // Next update time for hints should be updated.
   EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);

   LoadHint("host.domain.org");
   histogram_tester.ExpectTimeBucketCount(
       "OptimizationGuide.HintCache.FetchedHint.TimeToExpiration",
       optimization_guide::features::StoredFetchedHintsFreshnessDuration(), 1);
 }

 }  // namespace

 }  // namespace optimization_guide
	// Copyright 2018 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/optimization_guide/hint_cache.h"

	#include <string>
	#include <vector>

	#include "base/bind.h"
	#include "base/files/scoped_temp_dir.h"
	#include "base/macros.h"
	#include "base/run_loop.h"
	#include "base/strings/string_number_conversions.h"
	#include "base/test/metrics/histogram_tester.h"
	#include "base/test/task_environment.h"
	#include "components/optimization_guide/optimization_guide_features.h"
	#include "components/optimization_guide/optimization_guide_store.h"
	#include "components/optimization_guide/proto_database_provider_test_base.h"
	#include "testing/gtest/include/gtest/gtest.h"
	#include "url/gurl.h"

	namespace optimization_guide {
	namespace {

	std::string GetHostDomainOrg(int index) {
	return "host.domain" + base::NumberToString(index) + ".org";
	}

	class HintCacheTest : public ProtoDatabaseProviderTestBase {
	public:
	HintCacheTest() : loaded_hint_(nullptr) {}

	~HintCacheTest() override {}

	void SetUp() override { ProtoDatabaseProviderTestBase::SetUp(); }

	void TearDown() override {
	ProtoDatabaseProviderTestBase::TearDown();
	DestroyHintCache();
	}

	protected:
	// Creates and initializes the hint cache and optimization guide store and
	// waits for the callback indicating that initialization is complete.
	void CreateAndInitializeHintCache(int memory_cache_size,
	bool purge_existing_data = false) {
	auto database_path = temp_dir_.GetPath();
	auto database_task_runner = task_environment_.GetMainThreadTaskRunner();
	hint_cache_ = std::make_unique<HintCache>(
	std::make_unique<OptimizationGuideStore>(
	db_provider_.get(), database_path, database_task_runner),
	memory_cache_size);
	is_store_initialized_ = false;
	hint_cache_->Initialize(purge_existing_data,
	base::BindOnce(&HintCacheTest::OnStoreInitialized,
	base::Unretained(this)));
	while (!is_store_initialized_) {
	RunUntilIdle();
	}
	}

	void DestroyHintCache() {
	hint_cache_.reset();
	loaded_hint_ = nullptr;
	is_store_initialized_ = false;
	are_component_hints_updated_ = false;
	on_load_hint_callback_called_ = false;
	are_fetched_hints_updated_ = false;

	RunUntilIdle();
	}

	HintCache* hint_cache() { return hint_cache_.get(); }

	bool are_fetched_hints_updated() { return are_fetched_hints_updated_; }

	// Updates the cache with \|component_data\| and waits for callback indicating
	// that the update is complete.
	void UpdateComponentHints(std::unique_ptr<StoreUpdateData> component_data) {
	are_component_hints_updated_ = false;
	hint_cache_->UpdateComponentHints(
	std::move(component_data),
	base::BindOnce(&HintCacheTest::OnUpdateComponentHints,
	base::Unretained(this)));
	while (!are_component_hints_updated_) {
	RunUntilIdle();
	}
	}

	void UpdateFetchedHintsAndWait(
	std::unique_ptr<proto::GetHintsResponse> get_hints_response,
	base::Time stored_time) {
	are_fetched_hints_updated_ = false;
	hint_cache_->UpdateFetchedHints(
	std::move(get_hints_response), stored_time,
	base::BindOnce(&HintCacheTest::OnHintsUpdated, base::Unretained(this)));

	while (!are_fetched_hints_updated_)
	RunUntilIdle();
	}

	void OnHintsUpdated() { are_fetched_hints_updated_ = true; }

	// Loads hint for the specified host from the cache and waits for callback
	// indicating that loading the hint is complete.
	void LoadHint(const std::string& host) {
	on_load_hint_callback_called_ = false;
	loaded_hint_ = nullptr;
	hint_cache_->LoadHint(host, base::BindOnce(&HintCacheTest::OnLoadHint,
	base::Unretained(this)));
	while (!on_load_hint_callback_called_) {
	RunUntilIdle();
	}
	}

	const proto::Hint* GetLoadedHint() const { return loaded_hint_; }

	private:
	void RunUntilIdle() {
	task_environment_.RunUntilIdle();
	base::RunLoop().RunUntilIdle();
	}

	void OnStoreInitialized() { is_store_initialized_ = true; }
	void OnUpdateComponentHints() { are_component_hints_updated_ = true; }
	void OnLoadHint(const proto::Hint* hint) {
	on_load_hint_callback_called_ = true;
	loaded_hint_ = hint;
	}

	base::test::TaskEnvironment task_environment_;

	std::unique_ptr<HintCache> hint_cache_;
	const proto::Hint* loaded_hint_;

	bool is_store_initialized_;
	bool are_component_hints_updated_;
	bool on_load_hint_callback_called_;
	bool are_fetched_hints_updated_;

	DISALLOW_COPY_AND_ASSIGN(HintCacheTest);
	};

	TEST_F(HintCacheTest, ComponentUpdate) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Version version("2.0.0");
	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	ASSERT_TRUE(update_data);

	proto::Hint hint1;
	hint1.set_key("subdomain.domain.org");
	hint1.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint2;
	hint2.set_key("host.domain.org");
	hint2.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint3;
	hint3.set_key("otherhost.subdomain.domain.org");
	hint3.set_key_representation(proto::HOST_SUFFIX);

	update_data->MoveHintIntoUpdateData(std::move(hint1));
	update_data->MoveHintIntoUpdateData(std::move(hint2));
	update_data->MoveHintIntoUpdateData(std::move(hint3));

	UpdateComponentHints(std::move(update_data));

	// Not matched
	EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

	// Matched
	EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));
	}

	TEST_F(HintCacheTest, ComponentUpdateWithSameVersionIgnored) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Version version("2.0.0");
	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	ASSERT_TRUE(update_data);

	UpdateComponentHints(std::move(update_data));

	EXPECT_FALSE(hint_cache()->MaybeCreateUpdateDataForComponentHints(version));
	}

	TEST_F(HintCacheTest, ComponentUpdateWithEarlierVersionIgnored) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Version version_1("1.0.0");
	base::Version version_2("2.0.0");

	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version_2);
	ASSERT_TRUE(update_data);

	UpdateComponentHints(std::move(update_data));

	EXPECT_FALSE(hint_cache()->MaybeCreateUpdateDataForComponentHints(version_1));
	}

	TEST_F(HintCacheTest, ComponentUpdateWithLaterVersionProcessed) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Version version_1("1.0.0");
	base::Version version_2("2.0.0");

	std::unique_ptr<StoreUpdateData> update_data_1 =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version_1);
	ASSERT_TRUE(update_data_1);

	proto::Hint hint1;
	hint1.set_key("subdomain.domain.org");
	hint1.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint2;
	hint2.set_key("host.domain.org");
	hint2.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint3;
	hint3.set_key("otherhost.subdomain.domain.org");
	hint3.set_key_representation(proto::HOST_SUFFIX);

	update_data_1->MoveHintIntoUpdateData(std::move(hint1));
	update_data_1->MoveHintIntoUpdateData(std::move(hint2));
	update_data_1->MoveHintIntoUpdateData(std::move(hint3));

	UpdateComponentHints(std::move(update_data_1));

	// Not matched
	EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

	// Matched
	EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));

	std::unique_ptr<StoreUpdateData> update_data_2 =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version_2);
	ASSERT_TRUE(update_data_2);

	proto::Hint hint4;
	hint4.set_key("subdomain.domain2.org");
	hint4.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint5;
	hint5.set_key("host.domain2.org");
	hint5.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint6;
	hint6.set_key("otherhost.subdomain.domain2.org");
	hint6.set_key_representation(proto::HOST_SUFFIX);

	update_data_2->MoveHintIntoUpdateData(std::move(hint4));
	update_data_2->MoveHintIntoUpdateData(std::move(hint5));
	update_data_2->MoveHintIntoUpdateData(std::move(hint6));

	UpdateComponentHints(std::move(update_data_2));

	// Not matched
	EXPECT_FALSE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("host.subdomain.domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("domain2.org"));
	EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain2.org"));

	// Matched
	EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain2.org"));
	EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain2.org"));
	EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain2.org"));
	}

	TEST_F(HintCacheTest, ComponentHintsAvailableAfterRestart) {
	for (int i = 0; i < 2; ++i) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize,
	false /=purge_existing_data/);

	base::Version version("2.0.0");

	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	if (i == 0) {
	ASSERT_TRUE(update_data);

	proto::Hint hint1;
	hint1.set_key("subdomain.domain.org");
	hint1.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint2;
	hint2.set_key("host.domain.org");
	hint2.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint3;
	hint3.set_key("otherhost.subdomain.domain.org");
	hint3.set_key_representation(proto::HOST_SUFFIX);

	update_data->MoveHintIntoUpdateData(std::move(hint1));
	update_data->MoveHintIntoUpdateData(std::move(hint2));
	update_data->MoveHintIntoUpdateData(std::move(hint3));

	UpdateComponentHints(std::move(update_data));
	} else {
	EXPECT_FALSE(update_data);
	}

	// Not matched
	EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

	// Matched
	EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));

	DestroyHintCache();
	}
	}

	TEST_F(HintCacheTest, ComponentHintsUpdatableAfterRestartWithPurge) {
	for (int i = 0; i < 2; ++i) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize,
	true /=purge_existing_data/);

	base::Version version("2.0.0");

	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	ASSERT_TRUE(update_data);

	proto::Hint hint1;
	hint1.set_key("subdomain.domain.org");
	hint1.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint2;
	hint2.set_key("host.domain.org");
	hint2.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint3;
	hint3.set_key("otherhost.subdomain.domain.org");
	hint3.set_key_representation(proto::HOST_SUFFIX);

	update_data->MoveHintIntoUpdateData(std::move(hint1));
	update_data->MoveHintIntoUpdateData(std::move(hint2));
	update_data->MoveHintIntoUpdateData(std::move(hint3));

	UpdateComponentHints(std::move(update_data));

	// Not matched
	EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

	// Matched
	EXPECT_TRUE(hint_cache()->HasHint("otherhost.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("host.subdomain.domain.org"));
	EXPECT_TRUE(hint_cache()->HasHint("subhost.host.subdomain.domain.org"));

	DestroyHintCache();
	}
	}

	TEST_F(HintCacheTest, ComponentHintsNotRetainedAfterRestartWithPurge) {
	for (int i = 0; i < 2; ++i) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize,
	true /=purge_existing_data/);

	base::Version version("2.0.0");

	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	if (i == 0) {
	ASSERT_TRUE(update_data);

	proto::Hint hint1;
	hint1.set_key("subdomain.domain.org");
	hint1.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint2;
	hint2.set_key("host.domain.org");
	hint2.set_key_representation(proto::HOST_SUFFIX);
	proto::Hint hint3;
	hint3.set_key("otherhost.subdomain.domain.org");
	hint3.set_key_representation(proto::HOST_SUFFIX);

	update_data->MoveHintIntoUpdateData(std::move(hint1));
	update_data->MoveHintIntoUpdateData(std::move(hint2));
	update_data->MoveHintIntoUpdateData(std::move(hint3));

	UpdateComponentHints(std::move(update_data));
	} else {
	EXPECT_TRUE(update_data);
	}

	// Not matched
	EXPECT_FALSE(hint_cache()->HasHint("domain.org"));
	EXPECT_FALSE(hint_cache()->HasHint("othersubdomain.domain.org"));

	// Maybe matched
	bool should_match = (i == 0);
	EXPECT_EQ(hint_cache()->HasHint("otherhost.subdomain.domain.org"),
	should_match);
	EXPECT_EQ(hint_cache()->HasHint("host.subdomain.domain.org"), should_match);
	EXPECT_EQ(hint_cache()->HasHint("subhost.host.subdomain.domain.org"),
	should_match);

	DestroyHintCache();
	}
	}

	TEST_F(HintCacheTest, TestMemoryCacheLeastRecentlyUsedPurge) {
	const int kTestHintCount = 10;
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Version version("1.0.0");
	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	ASSERT_TRUE(update_data);

	for (int i = 0; i < kTestHintCount; ++i) {
	proto::Hint hint;
	hint.set_key(GetHostDomainOrg(i));
	hint.set_key_representation(proto::HOST_SUFFIX);
	update_data->MoveHintIntoUpdateData(std::move(hint));
	}

	UpdateComponentHints(std::move(update_data));

	for (int i = kTestHintCount - 1; i >= 0; --i) {
	std::string host = GetHostDomainOrg(i);
	EXPECT_TRUE(hint_cache()->HasHint(host));
	LoadHint(host);
	ASSERT_TRUE(GetLoadedHint());
	EXPECT_EQ(GetLoadedHint()->key(), host);
	}

	for (int i = 0; i < kTestHintCount; ++i) {
	std::string host = GetHostDomainOrg(i);
	if (i < kMemoryCacheSize) {
	ASSERT_TRUE(hint_cache()->GetHintIfLoaded(host));
	EXPECT_EQ(GetHostDomainOrg(i),
	hint_cache()->GetHintIfLoaded(host)->key());
	} else {
	EXPECT_FALSE(hint_cache()->GetHintIfLoaded(host));
	}
	EXPECT_TRUE(hint_cache()->HasHint(host));
	}
	}

	TEST_F(HintCacheTest, TestHostNotInCache) {
	const int kTestHintCount = 10;
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Version version("1.0.0");
	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	ASSERT_TRUE(update_data);

	for (int i = 0; i < kTestHintCount; ++i) {
	proto::Hint hint;
	hint.set_key(GetHostDomainOrg(i));
	hint.set_key_representation(proto::HOST_SUFFIX);
	update_data->MoveHintIntoUpdateData(std::move(hint));
	}

	UpdateComponentHints(std::move(update_data));

	EXPECT_FALSE(hint_cache()->HasHint(GetHostDomainOrg(kTestHintCount)));
	}

	TEST_F(HintCacheTest, TestMemoryCacheLoadCallback) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Version version("1.0.0");
	std::unique_ptr<StoreUpdateData> update_data =
	hint_cache()->MaybeCreateUpdateDataForComponentHints(version);
	ASSERT_TRUE(update_data);

	std::string hint_key = "subdomain.domain.org";
	proto::Hint hint;
	hint.set_key(hint_key);
	hint.set_key_representation(proto::HOST_SUFFIX);
	update_data->MoveHintIntoUpdateData(std::move(hint));

	UpdateComponentHints(std::move(update_data));

	EXPECT_FALSE(hint_cache()->GetHintIfLoaded("host.subdomain.domain.org"));
	LoadHint("host.subdomain.domain.org");
	EXPECT_TRUE(hint_cache()->GetHintIfLoaded("host.subdomain.domain.org"));

	EXPECT_TRUE(GetLoadedHint());
	EXPECT_EQ(hint_key, GetLoadedHint()->key());
	}

	TEST_F(HintCacheTest, StoreValidFetchedHints) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	// Default update time for empty optimization guide store is base::Time().
	EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), base::Time());

	std::unique_ptr<proto::GetHintsResponse> get_hints_response =
	std::make_unique<proto::GetHintsResponse>();

	proto::Hint* hint = get_hints_response->add_hints();
	hint->set_key_representation(proto::HOST_SUFFIX);
	hint->set_key("host.domain.org");
	proto::PageHint* page_hint = hint->add_page_hints();
	page_hint->set_page_pattern("page pattern");

	base::Time stored_time = base::Time().Now();
	UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
	EXPECT_TRUE(are_fetched_hints_updated());

	// Next update time for hints should be updated.
	EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);
	}

	TEST_F(HintCacheTest, ParseEmptyFetchedHints) {
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	base::Time stored_time = base::Time().Now() + base::TimeDelta().FromDays(1);
	std::unique_ptr<proto::GetHintsResponse> get_hints_response =
	std::make_unique<proto::GetHintsResponse>();

	UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
	// Empty Fetched Hints causes the metadata entry to be updated.
	EXPECT_TRUE(are_fetched_hints_updated());
	EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);
	}

	TEST_F(HintCacheTest, StoreValidFetchedHintsWithServerProvidedExpiryTime) {
	base::HistogramTester histogram_tester;
	const int kMemoryCacheSize = 5;
	const int kFetchedHintExpirationSecs = 60;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	// Default update time for empty optimization guide store is base::Time().
	EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), base::Time());

	std::unique_ptr<proto::GetHintsResponse> get_hints_response =
	std::make_unique<proto::GetHintsResponse>();

	// Set server-provided expiration time.
	get_hints_response->mutable_max_cache_duration()->set_seconds(
	kFetchedHintExpirationSecs);

	proto::Hint* hint = get_hints_response->add_hints();
	hint->set_key_representation(proto::HOST_SUFFIX);
	hint->set_key("host.domain.org");
	proto::PageHint* page_hint = hint->add_page_hints();
	page_hint->set_page_pattern("page pattern");

	base::Time stored_time = base::Time().Now();
	UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
	EXPECT_TRUE(are_fetched_hints_updated());

	// Next update time for hints should be updated.
	EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);

	LoadHint("host.domain.org");
	// HISTOGRAM TEST!
	histogram_tester.ExpectTimeBucketCount(
	"OptimizationGuide.HintCache.FetchedHint.TimeToExpiration",
	base::TimeDelta::FromSeconds(kFetchedHintExpirationSecs), 1);
	}

	TEST_F(HintCacheTest, StoreValidFetchedHintsWithDefaultExpiryTime) {
	base::HistogramTester histogram_tester;
	const int kMemoryCacheSize = 5;
	CreateAndInitializeHintCache(kMemoryCacheSize);

	// Default update time for empty optimization guide store is base::Time().
	EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), base::Time());

	std::unique_ptr<proto::GetHintsResponse> get_hints_response =
	std::make_unique<proto::GetHintsResponse>();

	proto::Hint* hint = get_hints_response->add_hints();
	hint->set_key_representation(proto::HOST_SUFFIX);
	hint->set_key("host.domain.org");
	proto::PageHint* page_hint = hint->add_page_hints();
	page_hint->set_page_pattern("page pattern");

	base::Time stored_time = base::Time().Now();
	UpdateFetchedHintsAndWait(std::move(get_hints_response), stored_time);
	EXPECT_TRUE(are_fetched_hints_updated());

	// Next update time for hints should be updated.
	EXPECT_EQ(hint_cache()->GetFetchedHintsUpdateTime(), stored_time);

	LoadHint("host.domain.org");
	histogram_tester.ExpectTimeBucketCount(
	"OptimizationGuide.HintCache.FetchedHint.TimeToExpiration",
	optimization_guide::features::StoredFetchedHintsFreshnessDuration(), 1);
	}

	} // namespace

	} // namespace optimization_guide