async Task Cancel(bool async, CancellationToken cancellationToken = default)
{
_state = ImporterState.Cancelled;
_buf.Clear();
_buf.EndCopyMode();
await _connector.WriteCopyFail(async, cancellationToken);
await _connector.Flush(async, cancellationToken);
try
{
using var registration = _connector.StartNestedCancellableOperation(cancellationToken, attemptPgCancellation: false);
var msg = await _connector.ReadMessage(async);
// The CopyFail should immediately trigger an exception from the read above.
throw _connector.Break(
new NpgsqlException("Expected ErrorResponse when cancelling COPY but got: " + msg.Code));
}
catch (PostgresException e)
{
if (e.SqlState != PostgresErrorCodes.QueryCanceled)
{
throw;
}
}
}
internal static PregeneratedMessage Generate(NpgsqlWriteBuffer buf, QueryMessage queryMessage, string query, int responseMessageCount = 2)
{
Debug.Assert(query != null && query.All(c => c < 128));
queryMessage.Populate(query);
var description = queryMessage.ToString();
queryMessage.Write(buf, false).Wait();
var bytes = buf.GetContents();
buf.Clear();
return(new PregeneratedMessage(bytes, description, responseMessageCount));
}
internal static byte[] Generate(NpgsqlWriteBuffer buf, string query)
{
Debug.Assert(query.All(c => c < 128));
var queryByteLen = Encoding.ASCII.GetByteCount(query);
buf.WriteByte(FrontendMessageCode.Query);
buf.WriteInt32(4 + // Message length (including self excluding code)
queryByteLen + // Query byte length
1); // Null terminator
buf.WriteString(query, queryByteLen, false).Wait();
buf.WriteByte(0);
var bytes = buf.GetContents();
buf.Clear();
return(bytes);
}