MIME Attachment Extractor

[httptech]

Description:

This is a short piece of code I wrote to enhance a online helpdesk system. It parses incoming emails, finds any attachments and saves them, then inserts into the email a link to where the saved attachments can be downloaded from.

In this code, the email is being read from STDIN, and the "cleaned" message (headers and body) is returned as a scalar.

You should take precautionary security measures on the directory that will hold the attachments; you obviously don't want to allow anyone to email you arbitrary code and run it from your public html directories.

use MIME::Parser;

sub read_email {
  my $dir = "/home/foo/public_html/attachments";
  my $url = "http://www.foo.bar/attachments";

  my $parser = new MIME::Parser;
  $parser->output_dir($dir);
  my $entity = $parser->read(\*STDIN) || die "couldn't parse MIME stre
+am";
  my $head = $entity->head;
  my $content = $head->as_string . "\n";

  my @parts = $entity->parts;
  my $body = $entity->bodyhandle;

  $content .= $body->as_string if defined $body;
  my $part;
  for $part (@parts) {
    my $path = ($part->bodyhandle) ? $part->bodyhandle->path : undef;
    if ($path =~ /msg-\d+.*\.doc/) {
      open(IN, $path) || warn "Couldn't open $path\n";
      local $/ = undef;
      $content .= <IN> . "\n";
      close IN;
      unlink ($path) || warn "Couldn't unlink $path\n";       
    }   
    else {
      my $file = $path;
      $file =~ s/$dir//o;
      $content .= "\n--\nSaved attachment: $url$file\n--\n"; }
    }

return $content;
}

[Punto]

I have 1 question: if the e-mail has only 1 part (the body of the msg), the .doc file is created, @parts is empty, and the file never gets deleted on the "for $part (@parts)" loop. Is there a way to get the name of the file when there are no attachments?

[Punto]

I got it! :)
Instead of using:

$content .= $body->as_string if defined $body;

I do:

if (defined $body) {
   $content .= $body->as_string;
   $filename = $body->path;
   unlink($filename);
};

and it works fine.. Thanks..

[httptech]

Yes, the bodies are always saved with the prefix "msg-" (unless you override it). So you can just unlink anything that starts with that prefix to clean out the message bodies.

[Punto]

What if while I'm deleting, another program is creating a file, and it's not done with it yet? The module Mime::Parse may lock the file, but then the sub open the file..