use strict;
package Email::Filter;
  $Email::Filter::VERSION = '1.034';
# ABSTRACT: Library for creating easy email filters

use Email::LocalDelivery;
use Email::Simple;
use Class::Trigger;
use IPC::Run qw(run);

use constant DELIVERED => 0;
use constant TEMPFAIL  => 75;
use constant REJECTED  => 100;

sub done_ok {
    my $self = shift;
    $self->{delivered} = 1;
    exit DELIVERED unless $self->{noexit};

sub fail_badly {
    my $self = shift;
    $self->{giveup} = 1; # Don't get caught by DESTROY
    exit TEMPFAIL unless $self->{noexit};
    warn "Message ".$self->simple->header("Message-ID").
          "was never handled properly\n";

sub fail_gracefully {
    my $self = shift;
    if ($self->{emergency} and ! $FAILING_GRACEFULLY) {
      local $FAILING_GRACEFULLY = 1;
      $self->done_ok if $self->accept($self->{emergency});

    my $self = shift;
    return if $self->{delivered}   # All OK.
           or $self->{giveup}      # Tried emergency, didn't work.
           or !$self->{emergency}; # Not much we can do.

sub new {
    my $class = shift;
    my %stuff = @_;
    my $data;

      local $/;
      $data = exists $stuff{data} ? $stuff{data} : scalar <STDIN>;
      # shave any leading From_ line
      $data =~ s/^From .*?[\x0a\x0d]//

    my $obj = bless {
        mail       => Email::Simple->new($data),
        emergency  => $stuff{emergency},
        noexit     => ($stuff{noexit} || 0)
    }, $class;
    return $obj;

sub exit { $_[0]->{noexit} = !$_[1]; }
sub noexit { $_[0]->{noexit} = $_[1]; }

sub simple {
    my ($filter, $mail) = @_;
    if ($mail) { $filter->{mail} = $mail; }
    return $filter->{mail};

sub header { my ($mail, $head) = @_; $mail->simple->header($head); }

sub body { $_[0]->simple->body }

{   no strict 'refs';
    for my $head (qw(From To CC Bcc Subject Received)) {
        *{lc $head} = sub { $_[0]->header($head) }

sub ignore {

sub accept {
    my ($self, @where) = @_;
    $self->call_trigger("before_accept", \@where);
    # Unparsing and reparsing is so fast we prefer to do that in order
    # to keep to LocalDelivery's clean interface.
    if (Email::LocalDelivery->deliver($self->simple->as_string, @where)) {
        $self->call_trigger("after_accept", \@where);
    } else {

sub reject {
    my $self = shift;
    $self->{delivered} = 1;
    $! = REJECTED; die @_,"\n";

sub pipe {
    my ($self, @program) = @_;
    my $arg;
    $arg = (ref $program[-1] eq 'HASH') ? (pop @program) : {};

    my $stdout;

    my $string = $arg->{header_only}
               ? $self->simple->header_obj->as_string
               : $self->simple->as_string;

    $self->call_trigger("pipe", \@program, $arg);
    if (eval {run(\@program, \$string, \$stdout)} ) {
        return $stdout;
    $self->fail_gracefully() unless $self->{noexit};




=encoding UTF-8

=head1 NAME

Email::Filter - Library for creating easy email filters

=head1 VERSION

version 1.034


    use Email::Filter;
    my $mail = Email::Filter->new(emergency => "~/emergency_mbox");
    $mail->pipe("listgate", "p5p")         if $mail->from =~ /perl5-porters/;
    $mail->accept("perl")                  if $mail->from =~ /perl/;
    $mail->reject("We do not accept spam") if $mail->subject =~ /enlarge/;
    $mail->ignore                          if $mail->subject =~ /boring/i;


This module replaces C<procmail> or C<Mail::Audit>, and allows you to write
programs describing how your mail should be filtered.

=head1 METHODS

=head2 new

    Email::Filter->new();                # Read from STDIN
    Email::Filter->new(data => $string); # Read from string

    Email::Filter->new(emergency => "~simon/urgh");
    # Deliver here in case of error

This takes an email either from standard input, the usual case when
called as a mail filter, or from a string.

You may also provide an "emergency" option, which is a filename to
deliver the mail to if it couldn't, for some reason, be handled

=over 3

=item Hint

If you put your constructor in a C<BEGIN> block, like so:

    use Email::Filter;
    BEGIN { $item = Email::Filter->new(emergency => "~simon/urgh"); }

right at the top of your mail filter script, you'll even be protected
from losing mail even in the case of syntax errors in your script. How
neat is that?


This method provides the C<new> trigger, called once an object is

=head2 exit


Sets or clears the 'exit' flag which determines whether or not the
following methods exit after successful completion.

The sense-inverted 'noexit' method is also provided for backwards
compatibility with C<Mail::Audit>, but setting "noexit" to "yes" got a
bit mind-bending after a while.

=head2 simple


Gets and sets the underlying C<Email::Simple> object for this filter;
see L<Email::Simple> for more details.

=head2 header


Returns the specified mail headers. In scalar context, returns the
first such header; in list context, returns them all.

=head2 body


Returns the body text of the email

=head2 from

=head2 to

=head2 cc

=head2 bcc

=head2 subject

=head2 received


Convenience accessors for C<header($header)>

=head2 ignore

Ignores this mail, exiting unconditionally unless C<exit> has been set
to false.

This method provides the "ignore" trigger.

=head2 accept


Accepts the mail into a given mailbox or mailboxes.
Unix C<~/> and C<~user/> prefices are resolved. If no mailbox is given,
the default is determined according to L<Email::LocalDelivery>:
C<$ENV{MAIL}>, F</var/spool/mail/you>, F</var/mail/you>, or

This provides the C<before_accept> and C<after_accept> triggers, and
exits unless C<exit> has been set to false.  They are passed a reference to the
C<@where> array.

=head2 reject

    $mail->reject("Go away!");

This rejects the email; if called in a pipe from a mail transport agent, (such
as in a F<~/.forward> file) the mail will be bounced back to the sender as
undeliverable. If a reason is given, this will be included in the bounce.

This calls the C<reject> trigger. C<exit> has no effect here.

=head2 pipe

    $mail->pipe(qw[sendmail foo\]);

Pipes the mail to an external program, returning the standard output
from that program if C<exit> has been set to false. The program and each
of its arguments must be supplied in a list. This allows you to do
things like:


in the absence of decent C<Mail::SpamAssassin> support.

If the program returns a non-zero exit code, the behaviour is dependent
on the status of the C<exit> flag. If this flag is set to true (the
default), then C<Email::Filter> tries to recover. (See L</ERROR RECOVERY>)
If not, nothing is returned.

If the last argument to C<pipe> is a reference to a hash, it is taken to
contain parameters to modify how C<pipe> itself behaves.  The only useful
parameter at this time is:

  header_only - only pipe the header, not the body


Users of C<Mail::Audit> will note that this class is much leaner than
the one it replaces. For instance, it has no logging; the concept of
"local options" has gone away, and so on. This is a deliberate design
decision to make the class as simple and maintainable as possible.

To make up for this, however, C<Email::Filter> contains a trigger
mechanism provided by L<Class::Trigger>, to allow you to add your own
functionality. You do this by calling the C<add_trigger> method:

    Email::Filter->add_trigger( after_accept => \&log_accept );

Hopefully this will also help subclassers.

The methods below will list which triggers they provide.


If something bad happens during the C<accept> or C<pipe> method, or
the C<Email::Filter> object gets destroyed without being properly
handled, then a fail-safe error recovery process is called. This first
checks for the existence of the C<emergency> setting, and tries to
deliver to that mailbox. If there is no emergency mailbox or that
delivery failed, then the program will either exit with a temporary
failure error code, queuing the mail for redelivery later, or produce a
warning to standard error, depending on the status of the C<exit>

=head1 AUTHORS

=over 4

=item *

Simon Cozens

=item *

Casey West

=item *

Ricardo SIGNES <>



This software is copyright (c) 2003 by Simon Cozens.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.