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[Thomas Berry <address@concealed>]

I have finally sorted out how to use message related variables (vars) 
within scenario rule conditions.

Scenario condition, message vars include:
 [msg_body]
 [msg_part->body]


When creating scenario rules that evaluate message content, two rules 
must be created when passing the contents of a message to a condition: 
one rule for plain text messages (msg_body) and a second rule for 
multi-part MIME messages (msg_part).

For example, I wrote a CustomCondition module that parses the URLs in a 
message and compares them with a list of approved URLs:

(send.url_eval)

title.us Moderated with URL verification
CustomCondition::urlreview([listname],[sender],[msg_body]) 
smtp,smime,md5 -> reject()
CustomCondition::urlreview([listname],[sender],[msg_part->body]) 
smtp,smime,md5 -> reject()
true() smtp,smime,md5 -> editorkey

The CustomCondition module returns undef if the message contents are not 
provided by the rule.  If the message contents are multi-part MIME, then 
the [msg_body] passed by the first rule is undefined, and the 
CustomCondition module returns undef causing the scenario to move on to 
the next rule which passes the parts of the multi-part MIME message to 
the module.


As for the CustomCondition module, it was written to evaluate both plain 
text (SCALAR) and multi-part MIME (ARRAY reference) being passed to the 
condition:

(urlreview.pm)

package CustomCondition::urlreview;
...
sub verify {
  my $listname = shift or return;
  my $sender   = shift or return;
  my $body;
  foreach my $part (@_) {
     $body .= ref $part eq "ARRAY" ? join " ", @{$part} : $part;
  }
  return unless defined $body;
...
}
...
1;


Scenario INCLUDE rule option:

Another thing to keep in mind when developing send rules that parse 
message content is that these rules must be added directly to the parent 
send scenario; when I was testing, it appears that the message vars 
(msg_body|msg_part) were not available to rules added to a scenario 
using the "include" [rule] option.

Thomas