DATA & lines starting with . (dot)

[karel-m]

send() method does not correctly handle a situation when data contains a line starting with . (dot).

According to: http://tools.ietf.org/html/rfc5321#section-4.5.2

Before sending a line of mail text, the SMTP client checks the
first character of the line.  If it is a period, one additional
period is inserted at the beginning of the line.

The current way of handling data value might be a feature. In that case I propose adding named argument data_esc which will handle the above mentioned escaping.

Here is a demonstration - in both cases the second line is missing the dot at the beginning. It also demonstrates that it cannot be "solved" by feeding data with a string created by MIME::Lite->new(..)->as_string. IMHO this escaping should happen in Mojo::SMTP::Client.

warn "A=" . $smtp->send(
        from => 'noreply@testdom.com',
        to   => 'karel@dom.com',
        data => join("\r\n", 'From: noreply@testdom.com',
                             'To: karel@dom.com',
                             'Subject: Dot test A',
                             '',
                             'first line',
                             '.second line starting with dot',
                             'last line',
                ),
        quit => 1
);

my $msg = MIME::Lite->new(
        From    => 'noreply@testdom.com',
        To      => 'karel@dom.com',
        Subject => 'Dot test B',
        Data    => join("\r\n", 
                             'first line',
                             '.second line starting with dot',
                             'last line',
                   ),
);

warn "B=" . $smtp->send(
        from => 'noreply@testdom.com',
        to   => 'karel@dom.com',
        data => $msg->as_string,
        quit => 1,
);

[olegwtf]

I agree, data should handle this. Can you provide patch?
I haven't time to fix this now.

[karel-m]

Initial idea is here: https://github.com/karel-m/p5-Mojo-SMTP-Client/commit/ea75bd07ad0650d0c3b627a4d6f29ff709832a16

After looking at https://metacpan.org/source/SHAY/libnet-3.08/lib/Net/Cmd.pm#L507 I am not sure whether we shouldn't also normalize newlines LF >> CRLF. Unfortunately straightforward replace like $line =~ s/\015?\012(\.?)/\015\012$1$1/sg; caused t/03_smtp_nb.t failure. I'll try to investigate more (basically the logic in Net::Cmd is even more complicated).

[karel-m]

Another improvement: https://github.com/karel-m/p5-Mojo-SMTP-Client/commit/259918048b79524ab25a0d11afa848198f929783

Now the replacing regexp is handling . escaping as well as CRLF normalization.

It works fine when data is the scalar with actual data (all at once), however there might be troubles when data is coderef and the sequence \r\n, is not in one chunk - like blexxxxx\r\n in one chunk and .blexxx in the next chunk.

It seems like we will inevitably end up mimicing sub datasend from Net::Cmd https://metacpan.org/source/SHAY/libnet-3.08/lib/Net/Cmd.pm#L459 (see $first_ch / $last_ch kung-fu)

[olegwtf]

Thanks
Just released version 0.11