/// <summary>
/// Tries to get the latest database with a prefix 'backup'
/// </summary>
/// <param name="cstr">Connection string to the server from which the latest database is picked</param>
/// <returns></returns>
private async Task <string> GetLatestOnlineBackupDatabase(SqlConnectionStringBuilder cstr)
{
// Connect to the master database
using (var connection = await cstr.ConnectToMaster())
{
// Get databases
var databases = await GetDatabases(connection, DatabaseState.ONLINE);
// Gather backups with matching prefix and order descending
var ordered = from db in databases
let backupMeta = db.GetBackupMetadata()
where backupMeta != null &&
String.Equals(
ExportPrefix,
backupMeta.Prefix,
StringComparison.OrdinalIgnoreCase)
orderby backupMeta.Timestamp descending
select backupMeta;
// Take the most recent one and check it's time
var mostRecent = ordered.FirstOrDefault();
if (mostRecent != null)
{
return(mostRecent.Db.name);
}
}
return(null);
}
private async Task <bool> DoesDBExist(SqlConnectionStringBuilder cstr, string name)
{
// Connect to the master database
using (var connection = await cstr.ConnectToMaster())
{
var db = await GetDatabase(connection, name);
return(db != null);
}
}
private async Task CleanExports(SqlConnectionStringBuilder cstr, DateTime timestampUtc)
{
using (var connection = await cstr.ConnectToMaster())
{
// Get databases
var databases = await GetDatabases(connection);
// Delete matching DBs
var toDelete = from d in databases
let backupMeta = d.GetBackupMetadata()
where backupMeta != null &&
String.Equals(
ExportPrefix,
backupMeta.Prefix,
StringComparison.OrdinalIgnoreCase) &&
backupMeta.Timestamp.UtcDateTime <= timestampUtc
select d;
foreach (var db in toDelete)
{
Log.DroppingDatabase(db.name);
await connection.ExecuteAsync("DROP DATABASE [" + db.name + "]");
}
}
}
