sync/internal_api/public/attachments/on_disk_attachment_store.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef SYNC_INTERNAL_API_PUBLIC_ATTACHMENTS_ON_DISK_ATTACHMENT_STORE_H_
   6 #define SYNC_INTERNAL_API_PUBLIC_ATTACHMENTS_ON_DISK_ATTACHMENT_STORE_H_
   7
   8 #include "base/files/file_path.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/threading/non_thread_safe.h"
  11 #include "sync/api/attachments/attachment.h"
  12 #include "sync/api/attachments/attachment_id.h"
  13 #include "sync/api/attachments/attachment_store.h"
  14 #include "sync/api/attachments/attachment_store_backend.h"
  15 #include "sync/base/sync_export.h"
  16
  17 namespace attachment_store_pb {
  18 class RecordMetadata;
  19 }  // namespace attachment_store_pb
  20
  21 namespace base {
  22 class SequencedTaskRunner;
  23 }  // namespace base
  24
  25 namespace leveldb {
  26 class DB;
  27 }  // namespace leveldb
  28
  29 namespace syncer {
  30
  31 // On-disk implementation of AttachmentStore. Stores attachments in leveldb
  32 // database in |path| directory.
  33 class SYNC_EXPORT OnDiskAttachmentStore : public AttachmentStoreBackend,
  34                                           public base::NonThreadSafe {
  35  public:
  36   // Constructs attachment store.
  37   OnDiskAttachmentStore(
  38       const scoped_refptr<base::SequencedTaskRunner>& callback_task_runner,
  39       const base::FilePath& path);
  40   ~OnDiskAttachmentStore() override;
  41
  42   // AttachmentStoreBackend implementation.
  43   void Init(const AttachmentStore::InitCallback& callback) override;
  44   void Read(const AttachmentIdList& ids,
  45             const AttachmentStore::ReadCallback& callback) override;
  46   void Write(AttachmentStore::Component component,
  47              const AttachmentList& attachments,
  48              const AttachmentStore::WriteCallback& callback) override;
  49   void SetReference(AttachmentStore::Component component,
  50                     const AttachmentIdList& ids) override;
  51   void DropReference(AttachmentStore::Component component,
  52                      const AttachmentIdList& ids,
  53                      const AttachmentStore::DropCallback& callback) override;
  54   void ReadMetadata(
  55       const AttachmentIdList& ids,
  56       const AttachmentStore::ReadMetadataCallback& callback) override;
  57   void ReadAllMetadata(
  58       AttachmentStore::Component component,
  59       const AttachmentStore::ReadMetadataCallback& callback) override;
  60
  61  private:
  62   friend class OnDiskAttachmentStoreSpecificTest;
  63
  64   // Opens leveldb database at |path|, creating it if needed. In the future
  65   // upgrade code will be invoked from OpenOrCreate as well. If open fails
  66   // result is UNSPECIFIED_ERROR.
  67   AttachmentStore::Result OpenOrCreate(const base::FilePath& path);
  68   // Reads single attachment from store. Returns nullptr in case of errors.
  69   scoped_ptr<Attachment> ReadSingleAttachment(
  70       const AttachmentId& attachment_id);
  71   // Writes single attachment to store. Returns false in case of errors.
  72   bool WriteSingleAttachment(const Attachment& attachment);
  73   // Reads single store_pb::RecordMetadata from levelDB into the provided
  74   // buffer. Returns false in case of an error.
  75   bool ReadSingleRecordMetadata(
  76       const AttachmentId& attachment_id,
  77       attachment_store_pb::RecordMetadata* record_metadata);
  78
  79   static std::string MakeDataKeyFromAttachmentId(
  80       const AttachmentId& attachment_id);
  81   static std::string MakeMetadataKeyFromAttachmentId(
  82       const AttachmentId& attachment_id);
  83   static AttachmentMetadata MakeAttachmentMetadata(
  84       const AttachmentId& attachment_id,
  85       const attachment_store_pb::RecordMetadata& record_metadata);
  86
  87   const base::FilePath path_;
  88   scoped_ptr<leveldb::DB> db_;
  89
  90   DISALLOW_COPY_AND_ASSIGN(OnDiskAttachmentStore);
  91 };
  92
  93 }  // namespace syncer
  94
  95 #endif  // SYNC_INTERNAL_API_PUBLIC_ATTACHMENTS_ON_DISK_ATTACHMENT_STORE_H_