{
* This Source Code Form is subject to the terms of the Mozilla Public License,
* v. 2.0. If a copy of the MPL was not distributed with this file, You can
* obtain one at http://mozilla.org/MPL/2.0/
*
* Copyright (C) 2006-2012, Peter Johnson (www.delphidabbler.com).
*
* $Rev$
* $Date$
*
* Static class that manages backups of data files. It can back up the local
* database directory, restore the backup and delete it.
}
unit UDataBackupMgr;
interface
uses
// Project
UBaseObjects;
type
{
TDataBackupMgr:
Static class that manages backups of main database. The database is backed
up into a single file.
}
TDataBackupMgr = class(TNoConstructObject)
strict private
const cBakFileID = SmallInt($CBAC); // Main database backup file ID
class function BackupFileName: string;
{Name of file used to receive database backup.
@return Required file name.
}
class function DataDir: string;
{Name of directory that contains main database files.
@return Required directory name.
}
class function BackupDir: string;
{Gets name of directory where backup file is stored.
@return Required directory name.
}
class function BackupExists: Boolean;
{Checks if a current backup file exists.
@return True if backup file exists, False if not.
}
class procedure DeleteFilesFromDir(const Dir: string);
{Deletes all files in a directory. Any sub directories are left untouched.
Takes no action if directory doesn't exist.
@param Dir [in] Name of directory files to be deleted from.
}
public
class procedure Backup;
{Backs up CodeSnip data files into a single file.
}
class procedure RestoreBackup;
{Restores back up, replacing current data files. If no backup exists the
database directory is cleared.
}
class procedure DeleteBackup;
{Deletes current backup file.
}
end;
implementation
uses
// Delphi
SysUtils, Windows {for inlining},
// Project
UAppInfo, UFolderBackup, UUtils;
{ TDataBackupMgr }
class procedure TDataBackupMgr.Backup;
{Backs up CodeSnip data files into a single file.
}
begin
EnsureFolders(BackupDir);
SysUtils.DeleteFile(BackupFileName);
EnsureFolders(DataDir);
with TFolderBackup.Create(DataDir, BackupFileName, cBakFileID) do
try
Backup;
finally
Free;
end;
end;
class function TDataBackupMgr.BackupDir: string;
{Gets name of directory where backup file is stored.
@return Required directory name.
}
begin
Result := ExcludeTrailingPathDelimiter(TAppInfo.UserAppDir);
end;
class function TDataBackupMgr.BackupExists: Boolean;
{Checks if a current backup file exists.
@return True if backup file exists, False if not.
}
begin
Result := FileExists(BackupFileName);
end;
class function TDataBackupMgr.BackupFileName: string;
{Name of file used to receive database backup.
@return Required file name.
}
begin
Result := IncludeTrailingPathDelimiter(BackupDir) + 'main-db.bak';
end;
class function TDataBackupMgr.DataDir: string;
{Name of directory that contains main database files.
@return Required directory name.
}
begin
Result := TAppInfo.AppDataDir;
end;
class procedure TDataBackupMgr.DeleteBackup;
{Deletes current backup file.
}
begin
if BackupExists then
SysUtils.DeleteFile(BackupFileName);
end;
class procedure TDataBackupMgr.DeleteFilesFromDir(const Dir: string);
{Deletes all files in a directory. Any sub directories are left untouched.
Takes no action if directory doesn't exist.
@param Dir [in] Name of directory files to be deleted from.
}
begin
if IsDirectory(Dir) then
DeleteFiles(Dir, '*.*');
end;
class procedure TDataBackupMgr.RestoreBackup;
{Restores back up, replacing current data files. If no backup exists the
database directory is cleared.
}
begin
EnsureFolders(DataDir);
DeleteFilesFromDir(DataDir);
if BackupExists then
begin
with TFolderBackup.Create(DataDir, BackupFileName, cBakFileID) do
try
Restore;
finally
Free;
end;
end;
end;
end.
