GDataDB support with leveldb.

chrome/browser/chromeos/gdata/gdata_leveldb.cc

+// Copyright (c) 2012 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 "chrome/browser/chromeos/gdata/gdata_leveldb.h"
+
+#include <string>
+
+#include "base/logging.h"
+#include "chrome/browser/chromeos/gdata/gdata_files.h"
+
+namespace gdata {
+
+// static
+scoped_ptr<GDataDB> GDataDB::Create(const FilePath& db_path) {
+  DVLOG(1) << "GDataDB::Create " << db_path.value();
+  GDataLevelDB* level_db = new GDataLevelDB();
+  level_db->Init(db_path);
+  return scoped_ptr<GDataDB>(level_db);
+}
+
+GDataLevelDB::GDataLevelDB() {
+}
+
+GDataLevelDB::~GDataLevelDB() {
+}
+
+void GDataLevelDB::Init(const FilePath& db_path) {
+  // Open the primary database with file_path key.
+  leveldb::DB* level_db = NULL;
+  leveldb::Options options;
+  options.create_if_missing = true;
+  leveldb::Status status = leveldb::DB::Open(options,
+      db_path.Append("main").value(), &level_db);
+  DCHECK(level_db);
+  DCHECK(status.ok());
+  main_db_.reset(level_db);
+  level_db = NULL;
+
+  // Secondary database keyed on path.
+  status = leveldb::DB::Open(options,
+      db_path.Append("path").value(), &level_db);
+  DCHECK(level_db);
+  DCHECK(status.ok());
+  path_db_.reset(level_db);
+}
+
+GDataDB::Status GDataLevelDB::Put(const GDataEntry& file) {
+  // TODO(achuith): Batch write operation
+  // Write the serialized proto.
+  std::string serialized_proto;
+  file.SerializeToString(&serialized_proto);
+  leveldb::Status status = main_db_->Put(
+      leveldb::WriteOptions(),
+      leveldb::Slice(file.resource_id()),
+      leveldb::Slice(serialized_proto));
+  if (!status.ok()) {
+    NOTREACHED();
+    DeleteByResourceId(file.resource_id());
+    return DB_ERR;
+  }
+
+  // Write the path.
+  status = path_db_->Put(
+      leveldb::WriteOptions(),
+      leveldb::Slice(file.file_name()),

[zel, 2012/04/23 18:44:52]

file_name() is not unique, you should use GetFilePath() instead

[achuithb, 2012/04/24 08:09:36]

Done.

+      leveldb::Slice(file.resource_id()));
+  if (!status.ok()) {
+    NOTREACHED();
+    DeleteByResourceId(file.resource_id());
+    return DB_ERR;
+  }
+  return DB_OK;
+}
+
+GDataDB::Status GDataLevelDB::DeleteByResourceId(
+    const std::string& resource_id) {
+  scoped_ptr<GDataEntry> file;
+  Status status = GetByResourceId(resource_id, &file);
+  if (status == DB_ERR)
+    return DB_ERR;
+  else if (status == DB_NOT_FOUND)
+    return DB_OK;
+
+  leveldb::Status db_status1 = main_db_->Delete(
+      leveldb::WriteOptions(),
+      leveldb::Slice(resource_id));
+
+  leveldb::Status db_status2 = path_db_->Delete(
+      leveldb::WriteOptions(),
+      leveldb::Slice(file->file_name()));

[zel, 2012/04/23 18:44:52]

file_name() is not the path, you should use path here

[achuithb, 2012/04/24 08:09:36]

Done.

+
+  return db_status1.ok() && db_status2.ok() ? DB_OK : DB_ERR;
+}
+
+GDataDB::Status GDataLevelDB::DeleteByPath(
+    const std::string& path) {
+  std::string resource_id;
+  const Status status = ResourceIdForPath(path, &resource_id);
+  if (status != DB_OK)
+    return status;
+  return DeleteByResourceId(resource_id);
+}
+
+GDataDB::Status GDataLevelDB::GetByResourceId(const std::string& resource_id,
+                                              scoped_ptr<GDataEntry>* file) {
+  file->reset();
+  std::string serialized_proto;
+  const leveldb::Status status = main_db_->Get(leveldb::ReadOptions(),
+                     leveldb::Slice(resource_id), &serialized_proto);
+
+  if (status.IsNotFound())
+    return DB_NOT_FOUND;
+
+  if (status.ok()) {
+    DCHECK(!serialized_proto.empty());
+    *file = GDataEntry::FromProtoString(serialized_proto);
+    DCHECK(file->get());
+    return DB_OK;
+  }
+  return DB_ERR;
+}
+
+GDataDB::Status GDataLevelDB::GetByPath(const std::string& path,
+                                        scoped_ptr<GDataEntry>* file) {
+  file->reset();
+  std::string resource_id;
+  const Status status = ResourceIdForPath(path, &resource_id);
+  if (status != DB_OK)
+    return status;
+  return GetByResourceId(resource_id, file);
+}
+
+scoped_ptr<GDataDBIter> GDataLevelDB::NewIterator(const std::string& path) {
+  // TODO(achuith): Implement this.
+  NOTREACHED();
+  return scoped_ptr<GDataDBIter>(NULL);
+}
+
+GDataDB::Status GDataLevelDB::ResourceIdForPath(const std::string& path,
+                                                std::string* resource_id) {
+  const leveldb::Status db_status = path_db_->Get(
+      leveldb::ReadOptions(), leveldb::Slice(path), resource_id);
+
+  if (db_status.ok())
+    return DB_OK;
+  else if (db_status.IsNotFound())
+    return DB_NOT_FOUND;
+  else
+    return DB_ERR;
+}
+
+}  // namespace gdata