Method dial

email/email.go:181–236

()

}

func (e *Email) dial() (*smtp.Client, error) {
	host, port, err := net.SplitHostPort(e.smtpAddress)
	if err != nil {
		return nil, err
	}

	// Always clone so we never mutate the caller's TLSConfig.
	var tlsConfig *tls.Config
	if e.TLSConfig == nil {
		tlsConfig = &tls.Config{ServerName: host}
	} else {
		tlsConfig = e.TLSConfig.Clone()
		if tlsConfig.ServerName == "" {
			tlsConfig.ServerName = host
		}
	}

	dialer := &net.Dialer{Timeout: e.DialTimeout}

	if port == "465" {
		conn, err := tls.DialWithDialer(dialer, "tcp", e.smtpAddress, tlsConfig)
		if err != nil {
			return nil, err
		}
		c, err := smtp.NewClient(conn, host)
		if err != nil {
			conn.Close()
			return nil, err
		}
		return c, nil
	}

	conn, err := dialer.Dial("tcp", e.smtpAddress)
	if err != nil {
		return nil, err
	}
	c, err := smtp.NewClient(conn, host)
	if err != nil {
		conn.Close()
		return nil, err
	}
	// Drive EHLO explicitly so we can surface its error. (*Client).Extension
	// triggers a lazy hello() and swallows its error, which would silently
	// treat a failed EHLO as "STARTTLS not advertised" and stay cleartext.
	if err := c.Hello("localhost"); err != nil {
		c.Close()
		return nil, err
	}
	if ok, _ := c.Extension("STARTTLS"); ok {
		if err := c.StartTLS(tlsConfig); err != nil {
			c.Close()
			return nil, err
		}
	}
	return c, nil
}