async Task BackupAsync()
{
this.events.StartingBackup();
Guid backupId = Guid.NewGuid();
string dbBackupDirectory = Path.Combine(this.backupPath, backupId.ToString());
BackupMetadata newBackupMetadata = new BackupMetadata(backupId, this.dataBackupRestore.DataBackupFormat, DateTime.UtcNow, this.dbStores.Keys.ToList());
BackupMetadataList backupMetadataList = new BackupMetadataList(new List <BackupMetadata> {
newBackupMetadata
});
try
{
Directory.CreateDirectory(dbBackupDirectory);
// Backup other stores.
foreach (string store in this.dbStores.Keys)
{
IDbStore dbStore = this.dbStoreProvider.GetDbStore(store);
await this.DbStoreBackupAsync(store, dbStore, dbBackupDirectory);
}
using (StreamWriter file = File.CreateText(Path.Combine(this.backupPath, BackupMetadataFileName)))
{
JsonSerializer serializer = new JsonSerializer();
serializer.Serialize(file, backupMetadataList);
}
this.events.BackupComplete();
// Clean any old backups.
this.CleanupUnknownBackups(this.backupPath, backupMetadataList);
}
catch (Exception exception)
{
this.events.BackupFailure($"The backup operation failed with error ${exception}.");
// Clean up any artifacts of the attempted backup.
this.CleanupKnownBackups(this.backupPath, backupMetadataList);
}
}
void CleanupKnownBackups(string backupPath, BackupMetadataList metadataList)
{
DirectoryInfo backupDirInfo = new DirectoryInfo(backupPath);
HashSet <string> knownBackupDirNames = new HashSet <string>(metadataList.Backups.Select(x => x.Id.ToString()), StringComparer.OrdinalIgnoreCase);
foreach (DirectoryInfo dir in backupDirInfo.GetDirectories())
{
if (knownBackupDirNames.Contains(dir.Name))
{
try
{
dir.Delete(true);
}
catch (Exception ex)
{
this.events.DeletionError(dir.FullName, ex);
}
}
}
this.events.BackupArtifactsCleanedUp();
}
async Task RestoreAsync()
{
string backupMetadataFilePath = Path.Combine(this.backupPath, BackupMetadataFileName);
if (!File.Exists(backupMetadataFilePath))
{
this.events.NoBackupsForRestore();
return;
}
try
{
string fileText = File.ReadAllText(backupMetadataFilePath);
BackupMetadataList backupMetadataList = JsonConvert.DeserializeObject <BackupMetadataList>(fileText);
BackupMetadata backupMetadata = backupMetadataList.Backups[0];
this.events.BackupInformation(backupMetadata.Id, backupMetadata.SerializationFormat, backupMetadata.TimestampUtc, backupMetadata.Stores);
string latestBackupDirPath = Path.Combine(this.backupPath, backupMetadata.Id.ToString());
if (Directory.Exists(latestBackupDirPath))
{
this.events.RestoringFromBackup(backupMetadata.Id);
foreach (string store in backupMetadata.Stores)
{
IDbStore dbStore;
if (!store.Equals(DefaultStoreBackupName, StringComparison.OrdinalIgnoreCase))
{
dbStore = this.GetDbStore(store);
}
else
{
dbStore = this.GetDbStore();
}
await this.DbStoreRestoreAsync(store, dbStore, latestBackupDirPath);
}
this.events.RestoreComplete();
}
else
{
this.events.NoBackupsForRestore();
}
}
catch (Exception exception)
{
this.events.RestoreFailure($"The restore operation failed with error ${exception}.");
// Clean up any restored state in the dictionary if the backup fails midway.
foreach (string store in this.dbStores.Keys.ToList())
{
this.RemoveDbStore(store);
}
this.RemoveDbStore();
}
finally
{
// Delete all other backups as we've either:
// 1. Restored successfully.
// 2. Failed during restore which would indicate a bad backup.
this.CleanupAllBackups(this.backupPath);
}
}
