remote_change_processor.h revision 4e180b6a0b4720a9b8e9e959a882386f690f08ff
1// Copyright (c) 2012 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 CHROME_BROWSER_SYNC_FILE_SYSTEM_REMOTE_CHANGE_PROCESSOR_H_ 6#define CHROME_BROWSER_SYNC_FILE_SYSTEM_REMOTE_CHANGE_PROCESSOR_H_ 7 8#include "base/basictypes.h" 9#include "base/callback_forward.h" 10#include "chrome/browser/sync_file_system/sync_callbacks.h" 11#include "chrome/browser/sync_file_system/sync_status_code.h" 12 13namespace base { 14class FilePath; 15} 16 17namespace fileapi { 18class FileSystemURL; 19} 20 21namespace sync_file_system { 22 23class FileChange; 24class FileChangeList; 25class SyncFileMetadata; 26 27// Represents an interface to process one remote change and applies 28// it to the local file system. 29// This interface is to be implemented/backed by LocalSyncFileService. 30class RemoteChangeProcessor { 31 public: 32 // Callback type for PrepareForProcessRemoteChange. 33 // |file_type| indicates the current file/directory type of the target 34 // URL in the local filesystem. If the target URL does not exist it is 35 // set to SYNC_FILE_TYPE_UNKNOWN. 36 // |changes| indicates a set of pending changes for the target URL. 37 typedef base::Callback<void( 38 SyncStatusCode status, 39 const SyncFileMetadata& metadata, 40 const FileChangeList& changes)> PrepareChangeCallback; 41 42 RemoteChangeProcessor() {} 43 virtual ~RemoteChangeProcessor() {} 44 45 // This must be called before processing the change for the |url|. 46 // This tries to lock the target |url| and returns the local changes 47 // if any. (The change returned by the callback is to make a decision 48 // on conflict resolution, but NOT for applying local changes to the remote, 49 // which is supposed to be done by LocalChangeProcessor) 50 virtual void PrepareForProcessRemoteChange( 51 const fileapi::FileSystemURL& url, 52 const PrepareChangeCallback& callback) = 0; 53 54 // This is called to apply the remote |change|. If the change type is 55 // ADD_OR_UPDATE for a file, |local_path| needs to point to a 56 // local file path that contains the latest file image (e.g. a path 57 // to a temporary file which has the data downloaded from the server). 58 // This may fail with an error but should NOT result in a conflict 59 // (as we must have checked the change status in PrepareRemoteSync and 60 // have disabled any further writing). 61 virtual void ApplyRemoteChange( 62 const FileChange& change, 63 const base::FilePath& local_path, 64 const fileapi::FileSystemURL& url, 65 const SyncStatusCallback& callback) = 0; 66 67 // Finalizes the remote sync started by PrepareForProcessRemoteChange. 68 // This clears sync flag on |url| to unlock the file for future writes/sync. 69 // Clears all local changes if |clear_local_changes| is true. 70 // This should be set to true when the remote sync service reconciled or 71 // processed the existing local changes while processing a remote change. 72 virtual void FinalizeRemoteSync( 73 const fileapi::FileSystemURL& url, 74 bool clear_local_changes, 75 const base::Closure& completion_callback) = 0; 76 77 // Records a fake local change so that the change will be processed in the 78 // next local sync. 79 // This is called when the remote side wants to trigger a local sync 80 // to propagate the local change to the remote change (e.g. to 81 // resolve a conflict by uploading the local file). 82 virtual void RecordFakeLocalChange( 83 const fileapi::FileSystemURL& url, 84 const FileChange& change, 85 const SyncStatusCallback& callback) = 0; 86 87 private: 88 DISALLOW_COPY_AND_ASSIGN(RemoteChangeProcessor); 89}; 90 91} // namespace sync_file_system 92 93#endif // CHROME_BROWSER_SYNC_FILE_SYSTEM_REMOTE_CHANGE_PROCESSOR_H_ 94