public async Task SendMessage(AddPrivateMessageDto message)
{
var connectionId = Context.ConnectionId;
var from = _userManager.GetUserById(connectionId);
message.From = from.Login;
var addedMessage = await _messageService.AddMessage(message);
var receiver = _userManager.GetUserByLogin(message.To);
var toConnectionId = string.Empty;
if (receiver != null)
{
toConnectionId = receiver.ConnectionId;
}
await Clients.Clients(toConnectionId, connectionId).MessageAdded(addedMessage);
}