/// <summary>
/// Saves this object to a file asynchronously
/// </summary>
/// <returns>A task that represents the asynchronous operation to save this object to a file</returns>
public Task SaveAsync()
{
return(Task.Run(() =>
{
if (!Directory.Exists(_directoryToStore))
{
Directory.CreateDirectory(_directoryToStore);
}
if (_isBackupEnabled && File.Exists(_filePath))
{
if (!Directory.Exists(_backupFolder))
{
Directory.CreateDirectory(_backupFolder);
}
var backupStamp = DateTime.Now;
var backUpPath =
Path.Combine(_backupFolder,
$"{_fileName}_{backupStamp.Day}-{backupStamp.Month}-{backupStamp.Year}-{backupStamp.Hour}-{backupStamp.Minute}-{backupStamp.Second}.bck");
if (File.Exists(backUpPath))
{
File.Delete(backUpPath);
}
File.Move(_filePath, backUpPath);
}
else if (!_isBackupEnabled && File.Exists(_filePath))
{
File.Delete(_filePath);
}
using (var fs = new FileStream(_filePath, FileMode.CreateNew))
{
using (var sw = new StreamWriter(fs))
{
sw.Write(_cryptoService.EncryptString(ObjectExtensions_Json.SerializeToJson(this)));
}
}
OnSaveFinished();
}));
}
/// <summary>
/// Loads this object from a file
/// </summary>
/// <typeparam name="T">Inherited type from <see cref="ApplicationFile"/></typeparam>
/// <param name="applicationFolder">The path to the directory for storing the file</param>
/// <param name="fileName">Name of the file</param>
/// <param name="cryptoService"><see cref="CoreLib.CORE.Interfaces.ICryptoService"/> implementation for file decryption</param>
/// <param name="isBackupEnabled">A flag indicating that backup files will be created. The backup will be stored in subdirectory named "Backup". The default value is false</param>
/// <returns>A task that represents the asynchronous operation of loading this object from a file. If there was a deserialization or decryption error, it deletes corrupted file and the return value will be null. If <paramref name="isBackupEnabled"/> is set to true, it tries to get an object from backup files</returns>
protected internal static Task <T> LoadAsync <T>(string applicationFolder, string fileName,
CryptoService cryptoService, bool isBackupEnabled = false) where T : ApplicationFile
{
return(Task.Run(() =>
{
var filePath = Path.Combine(applicationFolder, fileName);
var backupFolder = Path.Combine(applicationFolder, "Backup");
T applicationFile = null;
if (File.Exists(filePath))
{
try
{
using (var fs = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
{
using (var sr = new StreamReader(fs))
{
var jsonString = cryptoService.DecryptString(sr.ReadToEnd());
if (jsonString.IsNullOrEmptyOrWhiteSpace())
{
throw new ArgumentNullException(nameof(jsonString));
}
applicationFile = ObjectExtensions_Json.DeserializeFromJson <T>(jsonString);
}
}
}
catch
{
File.Delete(filePath);
if (!Directory.Exists(backupFolder))
{
return null;
}
foreach (var file in new DirectoryInfo(backupFolder).GetFiles($"{fileName}*")
.OrderByDescending(f => f.LastWriteTime))
{
try
{
using (var fs = new FileStream(file.FullName, FileMode.Open, FileAccess.Read,
FileShare.Read))
{
using (var sr = new StreamReader(fs))
{
var jsonString = cryptoService.DecryptString(sr.ReadToEnd());
if (jsonString.IsNullOrEmptyOrWhiteSpace())
{
throw new ArgumentNullException(nameof(jsonString));
}
applicationFile = ObjectExtensions_Json
.DeserializeFromJson <T>(jsonString);
}
File.Copy(file.FullName, filePath, true);
break;
}
}
catch
{
File.Delete(file.FullName);
}
}
}
}
applicationFile?.Init(applicationFolder, fileName, cryptoService, isBackupEnabled);
return applicationFile;
}));
}
