[SyncFS] Implement following four methods.

- CountFileMetadata
- CountFileTracker
- GetAllMeatadaIDs
- GetAllTrackerIDs


BUG=347425
TEST=./unit_tests --gtest_filter="Metadata*"

Review URL: https://codereview.chromium.org/372843007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@281980 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk.cc

@@ -359,15 +359,27 @@ size_t MetadataDatabaseIndexOnDisk::CountDirtyTracker() const {
 }
 
 size_t MetadataDatabaseIndexOnDisk::CountFileMetadata() const {
-  // TODO(peria): Implement here
-  NOTIMPLEMENTED();
-  return 0;
+  // TODO(peria): Cache the number of FileMetadata in the DB.
+  size_t count = 0;
+  scoped_ptr<leveldb::Iterator> itr(db_->NewIterator(leveldb::ReadOptions()));
+  for (itr->Seek(kFileMetadataKeyPrefix); itr->Valid(); itr->Next()) {
+    if (!StartsWithASCII(itr->key().ToString(), kFileMetadataKeyPrefix, true))
+      break;
+    ++count;
+  }
+  return count;
 }
 
 size_t MetadataDatabaseIndexOnDisk::CountFileTracker() const {
-  // TODO(peria): Implement here
-  NOTIMPLEMENTED();
-  return 0;
+  // TODO(peria): Cache the number of FileTracker in the DB.
+  size_t count = 0;
+  scoped_ptr<leveldb::Iterator> itr(db_->NewIterator(leveldb::ReadOptions()));
+  for (itr->Seek(kFileTrackerKeyPrefix); itr->Valid(); itr->Next()) {
+    if (!StartsWithASCII(itr->key().ToString(), kFileTrackerKeyPrefix, true))
+      break;
+    ++count;
+  }
+  return count;
 }
 
 std::vector<std::string>
@@ -384,16 +396,32 @@ MetadataDatabaseIndexOnDisk::GetRegisteredAppIDs() const {
 }
 
 std::vector<int64> MetadataDatabaseIndexOnDisk::GetAllTrackerIDs() const {
-  // TODO(peria): Implement here
-  NOTIMPLEMENTED();
-  return std::vector<int64>();
+  std::vector<int64> tracker_ids;
+  scoped_ptr<leveldb::Iterator> itr(db_->NewIterator(leveldb::ReadOptions()));
+  for (itr->Seek(kFileTrackerKeyPrefix); itr->Valid(); itr->Next()) {
+    std::string id_str;
+    if (!RemovePrefix(itr->key().ToString(), kFileTrackerKeyPrefix, &id_str))
+      break;
+
+    int64 tracker_id;
+    if (!base::StringToInt64(id_str, &tracker_id))
+      continue;
+    tracker_ids.push_back(tracker_id);
+  }
+  return tracker_ids;
 }
 
 std::vector<std::string>
 MetadataDatabaseIndexOnDisk::GetAllMetadataIDs() const {
-  // TODO(peria): Implement here
-  NOTIMPLEMENTED();
-  return std::vector<std::string>();
+  std::vector<std::string> file_ids;
+  scoped_ptr<leveldb::Iterator> itr(db_->NewIterator(leveldb::ReadOptions()));
+  for (itr->Seek(kFileMetadataKeyPrefix); itr->Valid(); itr->Next()) {
+    std::string file_id;
+    if (!RemovePrefix(itr->key().ToString(), kFileMetadataKeyPrefix, &file_id))
+      break;
+    file_ids.push_back(file_id);
+  }
+  return file_ids;
 }
 
 void MetadataDatabaseIndexOnDisk::AddToAppIDIndex(

chrome/browser/sync_file_system/drive_backend/metadata_database_index_on_disk_unittest.cc

@@ -183,6 +183,27 @@ TEST_F(MetadataDatabaseIndexOnDiskTest, SetEntryTest) {
   EXPECT_FALSE(index()->GetFileTracker(tracker_id, NULL));
 }
 
+TEST_F(MetadataDatabaseIndexOnDiskTest, AllEntriesTest) {
+  CreateTestDatabase(true);
+
+  EXPECT_EQ(3U, index()->CountFileMetadata());
+  std::vector<std::string> file_ids(index()->GetAllMetadataIDs());
+  ASSERT_EQ(3U, file_ids.size());
+  std::sort(file_ids.begin(), file_ids.end());
+  EXPECT_EQ("app_root_folder_id", file_ids[0]);
+  EXPECT_EQ("file_id", file_ids[1]);
+  EXPECT_EQ("sync_root_folder_id", file_ids[2]);
+
+  EXPECT_EQ(4U, index()->CountFileTracker());
+  std::vector<int64> tracker_ids = index()->GetAllTrackerIDs();
+  ASSERT_EQ(4U, tracker_ids.size());
+  std::sort(tracker_ids.begin(), tracker_ids.end());
+  EXPECT_EQ(kSyncRootTrackerID, tracker_ids[0]);
+  EXPECT_EQ(kAppRootTrackerID, tracker_ids[1]);
+  EXPECT_EQ(kFileTrackerID, tracker_ids[2]);
+  EXPECT_EQ(kPlaceholderTrackerID, tracker_ids[3]);
+}
+
 TEST_F(MetadataDatabaseIndexOnDiskTest, IndexAppRootIDByAppIDTest) {
   CreateTestDatabase(true);