/// <summary>
/// <inheritdoc />
/// </summary>
public async Task <TransportMessage[]> Retrieve(CancellationToken cancellationToken, int topMessages)
{
var messages = new List <TransportMessage>();
using (var connection = await _connectionFactory().ConfigureAwait(false))
{
if (connection.State != ConnectionState.Open)
{
await connection.OpenAsync(cancellationToken).ConfigureAwait(false);
}
using (var command = connection.CreateCommand())
{
command.CommandText =
$@"
DELETE TOP({topMessages})
FROM {_tableName} WITH (READPAST, ROWLOCK, READCOMMITTEDLOCK)
OUTPUT deleted.headers, deleted.body
";
using (var reader = await command.ExecuteReaderAsync(cancellationToken).ConfigureAwait(false))
{
while (await reader.ReadAsync(cancellationToken).ConfigureAwait(false))
{
var headers = _headerSerializer.DeserializeFromString((string)reader["headers"]);
var body = (byte[])reader["body"];
messages.Add(new TransportMessage(headers, body));
}
}
}
}
return(messages.ToArray());
}
/// <summary>
/// Gets messages due for delivery at the current time
/// </summary>
public async Task <DueMessagesResult> GetDueMessages()
{
var connection = await _connectionProvider.GetConnection();
try
{
var dueMessages = new List <DueMessage>();
const int maxDueTimeouts = 1000;
using (var command = connection.CreateCommand())
{
command.CommandText =
$@"
SELECT
[id],
[headers],
[body]
FROM {_tableName.QualifiedName} WITH (UPDLOCK, READPAST, ROWLOCK)
WHERE [due_time] <= @current_time
ORDER BY [due_time] ASC
";
command.Parameters.Add("current_time", SqlDbType.DateTime2).Value = RebusTime.Now.UtcDateTime;
using (var reader = command.ExecuteReader())
{
while (reader.Read())
{
var id = (int)reader["id"];
var headersString = (string)reader["headers"];
var headers = HeaderSerializer.DeserializeFromString(headersString);
var body = (byte[])reader["body"];
var sqlTimeout = new DueMessage(headers, body, async() =>
{
using (var deleteCommand = connection.CreateCommand())
{
deleteCommand.CommandText = $"DELETE FROM {_tableName.QualifiedName} WHERE [id] = @id";
deleteCommand.Parameters.Add("id", SqlDbType.Int).Value = id;
await deleteCommand.ExecuteNonQueryAsync();
}
});
dueMessages.Add(sqlTimeout);
if (dueMessages.Count >= maxDueTimeouts)
{
break;
}
}
}
return(new DueMessagesResult(dueMessages, async() =>
{
using (connection)
{
await connection.Complete();
}
}));
}
}
catch (Exception)
{
connection.Dispose();
throw;
}
}
/// <summary>
/// Gets messages due for delivery at the current time
/// </summary>
public async Task <DueMessagesResult> GetDueMessages()
{
var connection = await _connectionProvider.GetConnectionAsync().ConfigureAwait(false);
try
{
var dueMessages = new List <DueMessage>();
const int maxDueTimeouts = 1000;
using (var command = connection.CreateCommand())
{
var tableName = _tableName.QualifiedName;
command.CommandText = $@"
SELECT id,
headers,
body
FROM {tableName}
WHERE due_time <= @current_time
ORDER BY due_time ASC
FOR UPDATE";
command.Parameters.Add("current_time", MySqlDbType.DateTime).Value = _rebusTime.Now.UtcDateTime;
using (var reader = await command.ExecuteReaderAsync().ConfigureAwait(false))
{
while (await reader.ReadAsync().ConfigureAwait(false))
{
var id = (long)reader["id"];
var headersString = (string)reader["headers"];
var headers = HeaderSerializer.DeserializeFromString(headersString);
var body = (byte[])reader["body"];
var sqlTimeout = new DueMessage(headers, body, async() =>
{
using (var deleteCommand = connection.CreateCommand())
{
deleteCommand.CommandText = $"DELETE FROM {tableName} WHERE id = {id}";
await deleteCommand.ExecuteNonQueryAsync().ConfigureAwait(false);
}
});
dueMessages.Add(sqlTimeout);
if (dueMessages.Count >= maxDueTimeouts)
{
break;
}
}
}
return(new DueMessagesResult(dueMessages, async() =>
{
using (connection)
{
await connection.CompleteAsync().ConfigureAwait(false);
}
}));
}
}
catch (Exception)
{
connection.Dispose();
throw;
}
}
