import { MessageSender, SentMessage, Email, EmailAddress } from '../../api';
import { EmailError } from '../../api/exception/MessageError';
import { SmtpConfiguration, ConfigureSmtpTransport } from './email-utils';
export declare class SmtpError extends EmailError {
}
export declare class SmtpEmailSender implements MessageSender {
    private smtpConf;
    private defaults;
    private mailer;
    constructor(smtpConf: SmtpConfiguration, defaults: Partial<Email>, mailer: ConfigureSmtpTransport);
    private transporter;
    send(email: Email): Promise<SentMessage>;
    toSmtpMessage(email: Email): any;
    toSmtpAddress(address?: EmailAddress | string): string | null;
}