RC: Implement the GetDatabaseSize interface.

A subsequent CL will plumb this out to the chrome://discards page.

Bug: 874968
Change-Id: I18496f73a4a76cfe05151b67fb7cce4d9e256064
Reviewed-on: https://chromium-review.googlesource.com/1239002
Commit-Queue: Sigurður Ásgeirsson <siggi@chromium.org>
Reviewed-by: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593607}

chrome/browser/resource_coordinator/leveldb_site_characteristics_database.cc

@@ -15,6 +15,7 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/task_runner_util.h"
 #include "base/threading/scoped_blocking_call.h"
+#include "build/build_config.h"
 #include "chrome/browser/resource_coordinator/utils.h"
 #include "third_party/leveldatabase/env_chromium.h"
 #include "third_party/leveldatabase/leveldb_chrome.h"
@@ -84,6 +85,11 @@ bool ShouldAttemptDbRepair(const leveldb::Status& status) {
   return false;
 }
 
+struct DatabaseSizeResult {
+  base::Optional<int64_t> num_rows;
+  base::Optional<int64_t> on_disk_size_kb;
+};
+
 }  // namespace
 
 // Version history:
@@ -135,6 +141,8 @@ class LevelDBSiteCharacteristicsDatabase::AsyncHelper {
   void RemoveSiteCharacteristicsFromDB(
       const std::vector<url::Origin>& site_origin);
   void ClearDatabase();
+  // Returns a struct with unset fields on failure.
+  DatabaseSizeResult GetDatabaseSize();
 
   bool DBIsInitialized() { return db_ != nullptr; }
 
@@ -295,6 +303,40 @@ void LevelDBSiteCharacteristicsDatabase::AsyncHelper::ClearDatabase() {
   }
 }
 
+DatabaseSizeResult
+LevelDBSiteCharacteristicsDatabase::AsyncHelper::GetDatabaseSize() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  if (!db_)
+    return DatabaseSizeResult();
+
+  base::ScopedBlockingCall scoped_blocking_call(base::BlockingType::MAY_BLOCK);
+  DatabaseSizeResult ret;
+#if defined(OS_WIN)
+  // Windows has an annoying mis-feature that the size of an open file is not
+  // written to the parent directory until the file is closed. Since this is a
+  // diagnostic interface that should be rarely called, go to the trouble of
+  // closing and re-opening the database in order to get an up-to date size to
+  // report.
+  db_.reset();
+#endif
+  ret.on_disk_size_kb = base::ComputeDirectorySize(db_path_) / 1024;
+#if defined(OS_WIN)
+  OpenOrCreateDatabase();
+  if (!db_)
+    return DatabaseSizeResult();
+#endif
+
+  // Default read options will fill the cache as we go.
+  std::unique_ptr<leveldb::Iterator> iterator(
+      db_->NewIterator(leveldb::ReadOptions()));
+  int64_t num_rows = 0;
+  for (iterator->SeekToFirst(); iterator->Valid(); iterator->Next())
+    ++num_rows;
+
+  ret.num_rows = num_rows;
+  return ret;
+}
+
 LevelDBSiteCharacteristicsDatabase::AsyncHelper::OpeningType
 LevelDBSiteCharacteristicsDatabase::AsyncHelper::OpenOrCreateDatabaseImpl() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
@@ -408,6 +450,25 @@ void LevelDBSiteCharacteristicsDatabase::ClearDatabase() {
           base::Unretained(async_helper_.get())));
 }
 
+void LevelDBSiteCharacteristicsDatabase::GetDatabaseSize(
+    GetDatabaseSizeCallback callback) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+
+  // Adapt the callback with a lambda to allow using PostTaskAndReplyWithResult.
+  auto reply_callback = base::BindOnce(
+      [](GetDatabaseSizeCallback callback, const DatabaseSizeResult& result) {
+        std::move(callback).Run(result.num_rows, result.on_disk_size_kb);
+      },
+      std::move(callback));
+
+  base::PostTaskAndReplyWithResult(
+      blocking_task_runner_.get(), FROM_HERE,
+      base::BindOnce(
+          &LevelDBSiteCharacteristicsDatabase::AsyncHelper::GetDatabaseSize,
+          base::Unretained(async_helper_.get())),
+      std::move(reply_callback));
+}
+
 bool LevelDBSiteCharacteristicsDatabase::DatabaseIsInitializedForTesting() {
   return async_helper_->DBIsInitialized();
 }

chrome/browser/resource_coordinator/leveldb_site_characteristics_database.h

@@ -42,6 +42,7 @@ class LevelDBSiteCharacteristicsDatabase
   void RemoveSiteCharacteristicsFromDB(
       const std::vector<url::Origin>& site_origins) override;
   void ClearDatabase() override;
+  void GetDatabaseSize(GetDatabaseSizeCallback callback) override;
 
   bool DatabaseIsInitializedForTesting();
 

chrome/browser/resource_coordinator/leveldb_site_characteristics_database_unittest.cc

@@ -11,6 +11,7 @@
 #include "base/files/scoped_temp_dir.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
+#include "base/test/bind_test_util.h"
 #include "base/test/metrics/histogram_tester.h"
 #include "base/test/scoped_task_environment.h"
 #include "base/test/test_file_util.h"
@@ -122,10 +123,9 @@ class LevelDBSiteCharacteristicsDatabaseTest : public ::testing::Test {
   }
 
   // Add some entries to the database and returns a vector with their origins.
-  std::vector<url::Origin> AddDummyEntriesToDB() {
-    const size_t kEntryCount = 10;
+  std::vector<url::Origin> AddDummyEntriesToDB(size_t num_entries) {
     std::vector<url::Origin> site_origins;
-    for (size_t i = 0; i < kEntryCount; ++i) {
+    for (size_t i = 0; i < num_entries; ++i) {
       SiteCharacteristicsProto proto_temp;
       std::string origin_str = base::StringPrintf("http://%zu.com", i);
       InitSiteCharacteristicProto(&proto_temp,
@@ -166,7 +166,7 @@ TEST_F(LevelDBSiteCharacteristicsDatabaseTest, InitAndStoreSiteCharacteristic) {
 }
 
 TEST_F(LevelDBSiteCharacteristicsDatabaseTest, RemoveEntries) {
-  std::vector<url::Origin> site_origins = AddDummyEntriesToDB();
+  std::vector<url::Origin> site_origins = AddDummyEntriesToDB(10);
 
   // Remove half the origins from the database.
   std::vector<url::Origin> site_origins_to_remove(
@@ -195,8 +195,33 @@ TEST_F(LevelDBSiteCharacteristicsDatabaseTest, RemoveEntries) {
     EXPECT_FALSE(ReadFromDB(iter, &proto_temp));
 }
 
+TEST_F(LevelDBSiteCharacteristicsDatabaseTest, GetDatabaseSize) {
+  std::vector<url::Origin> site_origins = AddDummyEntriesToDB(200);
+
+  auto size_callback =
+      base::BindLambdaForTesting([&](base::Optional<int64_t> num_rows,
+                                     base::Optional<int64_t> on_disk_size_kb) {
+        EXPECT_TRUE(num_rows);
+        // The DB contains an extra row for metadata.
+        int64_t expected_rows = site_origins.size() + 1;
+        EXPECT_EQ(expected_rows, num_rows.value());
+
+        EXPECT_TRUE(on_disk_size_kb);
+        EXPECT_LT(0, on_disk_size_kb.value());
+      });
+
+  db_->GetDatabaseSize(std::move(size_callback));
+
+  WaitForAsyncOperationsToComplete();
+
+  // Verify that the DB is still operational (see implementation detail
+  // for Windows).
+  SiteCharacteristicsProto read_proto;
+  EXPECT_TRUE(ReadFromDB(site_origins[0], &read_proto));
+}
+
 TEST_F(LevelDBSiteCharacteristicsDatabaseTest, DatabaseRecoveryTest) {
-  std::vector<url::Origin> site_origins = AddDummyEntriesToDB();
+  std::vector<url::Origin> site_origins = AddDummyEntriesToDB(10);
 
   db_.reset();
 

chrome/browser/resource_coordinator/local_site_characteristics_data_unittest_utils.cc

@@ -82,6 +82,11 @@ void NoopLocalSiteCharacteristicsDatabase::RemoveSiteCharacteristicsFromDB(
 
 void NoopLocalSiteCharacteristicsDatabase::ClearDatabase() {}
 
+void NoopLocalSiteCharacteristicsDatabase::GetDatabaseSize(
+    GetDatabaseSizeCallback callback) {
+  std::move(callback).Run(base::nullopt, base::nullopt);
+}
+
 ChromeTestHarnessWithLocalDB::ChromeTestHarnessWithLocalDB() {
   scoped_feature_list_.InitAndEnableFeature(
       features::kSiteCharacteristicsDatabase);

chrome/browser/resource_coordinator/local_site_characteristics_data_unittest_utils.h

@@ -72,6 +72,7 @@ class NoopLocalSiteCharacteristicsDatabase
   void RemoveSiteCharacteristicsFromDB(
       const std::vector<url::Origin>& site_origins) override;
   void ClearDatabase() override;
+  void GetDatabaseSize(GetDatabaseSizeCallback callback) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NoopLocalSiteCharacteristicsDatabase);

chrome/browser/resource_coordinator/local_site_characteristics_database.h

@@ -25,6 +25,9 @@ class LocalSiteCharacteristicsDatabase {
   // initialization has failed.
   using ReadSiteCharacteristicsFromDBCallback = base::OnceCallback<void(
       base::Optional<SiteCharacteristicsProto> site_characteristic_proto)>;
+  using GetDatabaseSizeCallback =
+      base::OnceCallback<void(base::Optional<int64_t> num_rows,
+                              base::Optional<int64_t> on_disk_size_kb)>;
 
   LocalSiteCharacteristicsDatabase() = default;
   virtual ~LocalSiteCharacteristicsDatabase() {}
@@ -48,6 +51,9 @@ class LocalSiteCharacteristicsDatabase {
 
   // Clear the database, removes every entries that it contains.
   virtual void ClearDatabase() = 0;
+
+  // Retrieve the size of the database.
+  virtual void GetDatabaseSize(GetDatabaseSizeCallback callback) = 0;
 };
 
 }  // namespace resource_coordinator