Download Service : Added leveldb proto layer

components/download/internal/download_store.h

+// 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.
+
+#ifndef COMPONENTS_DOWNLOAD_INTERNAL_DOWNLOAD_STORE_H_
+#define COMPONENTS_DOWNLOAD_INTERNAL_DOWNLOAD_STORE_H_
+
+#include <string>
+#include <vector>
+
+#include "base/files/file_path.h"
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "components/download/internal/store.h"
+#include "components/leveldb_proto/proto_database.h"
+
+namespace protodb {
+class Entry;
+
+}  // namespace
+
+namespace download {
+
+// DownloadStore provides a layer around a LevelDB proto database that persists
+// the download request, scheduling params and metadata to the disk. The data is
+// read during initialization and presented to the caller after converting to
+// Entry entries.
+class DownloadStore : public Store {
+ public:
+  DownloadStore(
+      const base::FilePath& database_dir,
+      std::unique_ptr<leveldb_proto::ProtoDatabase<protodb::Entry>> db);
+  ~DownloadStore() override;
+
+  // Store implementation.
+  bool IsInitialized() override;
+  void Initialize(const InitCallback& callback) override;
+  void Destroy(const StoreCallback& callback) override;
+  void Update(const Entry& entry, const StoreCallback& callback) override;
+  void Remove(const std::string& guid, const StoreCallback& callback) override;
+
+ private:
+  void OnDatabaseInited(const InitCallback& callback, bool success);
+  void OnDatabaseLoaded(const InitCallback& callback,
+                        bool success,
+                        std::unique_ptr<std::vector<protodb::Entry>> protos);
+
+  std::unique_ptr<leveldb_proto::ProtoDatabase<protodb::Entry>> db_;
+  base::FilePath database_dir_;
+  bool is_initialized_;
+
+  base::WeakPtrFactory<DownloadStore> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(DownloadStore);
+};
+
+}  // namespace download
+
+#endif  // COMPONENTS_DOWNLOAD_INTERNAL_DOWNLOAD_STORE_H_