#!/bin/sh
# -*- sh -*-

: << =cut

=head1 NAME

postfix_mailqueue - Plugin to monitor postfix mail spools

=head1 ABOUT

A guide to postfix mail queue manageent can be found at
L<http://www.postfix.org/QSHAPE_README.html#queues>

A summary:

=over 4

=item maildrop

Messages that have been submitted via the Postfix sendmail(1) command,
but not yet brought into the main Postfix queue by the pickup(8)
service.

=item hold

Messages placed in the "hold" queue stay there until the administrator
intervenes

=item incoming

Inbound mail from the network.

=item outgoing

Mails that are sent to the network.

=item deferred

Mail that could not be delivered upon the first attempt. The queue manager
implements exponential backoff by doubling the time between delivery attempts.

=item corrupt

Unreadable or damaged queue files are moved here for inspection.

=back

=head1 CONFIGURATION

By default "postconf -h queue_directory" is used to determine the
spool directory.  Is postconf is not available in the $PATH then
/var/spool/postfix is assumed.  This can be overridden by the
"spooldir" environment variable like so:

 [postfix_mailqueue]
    env.spooldir /var/spool/postfix
    env.maillog /var/log/mail.log

=head1 AUTHOR

Unknown.

=head1 LICENSE

Unknown.

=head1 MAGIC MARKERS

=begin comment

These magic markers are used by munin-node-configure when installing
munin-node.

=end comment

 #%# family=auto
 #%# capabilities=autoconf

=cut

MAILLOG=${maillog:-/var/log/mail.log}
MINUTES=${minutes:-5}
OUTGOING_REGEX=${outgoing_regex:-"postfix/smtp\[.*status=sent"}
INCOMING_REGEX=${incoming_regex:-"postfix/pipe\[.*status=sent"}

# atempt to get spooldir via postconf, but environment overrides.

# Remember that postconf is not available unless postfix is.
POSTCONFSPOOL="$(postconf -h queue_directory 2>/dev/null || echo /var/spool/postfix)"
SPOOLDIR=${spooldir:-$POSTCONFSPOOL}

. $MUNIN_LIBDIR/plugins/plugin.sh

syslogXmins() {
	MINUTES_MINUS_ONE=`expr $MINUTES - 1`
	#for (( i = $MINUTES; i > 0; i-- )) ; do
	for i in $(seq 0 $MINUTES_MINUS_ONE) ; do
		# In %_d the underscore is important since it demands `date`
		# to pad with spaces (like syslog for e.g. "Jan  1" to "Jan  9")
		# instead of zeros.
		dstring=`LANG=C date -d "-$i min" +"%b %_d %R"`
		#echo "Entries for '$dstring':"
		grep "^$dstring:.. " $1
	done
}

# main logic

case $1 in
    autoconf|detect)
	if [ -d $SPOOLDIR ] ; then
	    echo yes
	    exit 0
        else
	    echo "no (spooldir not found)"
	    exit 0
    fi;;

    config)
	cat <<'EOF'
graph_title Postfix Mailqueue
graph_vlabel Mails in queue
graph_category postfix
outgoing.label outgoing
outgoing.info Outbound mail to the network
deferred.label deferred
deferred.info Mail queued for later delivery
maildrop.label maildrop
maildrop.info Not yet picked up mail submitted via Postfix sendmail(1) command
incoming.label incoming
incoming.info Inbound mail from the network
corrupt.label corrupt
corrupt.info Unreadable or damaged queue files
hold.label held
hold.info Messages placed in the "hold" queue awaiting administrator intervention
EOF
	for field in outgoing deferred maildrop incoming corrupt hold; do
		print_warning $field
		print_critical $field
	done
	exit 0;;
esac

cd $SPOOLDIR >/dev/null 2>/dev/null || {
     echo "# Cannot cd to $SPOOLDIR"
     exit 1
}

cat <<EOF
outgoing.value `syslogXmins $MAILLOG | grep "$OUTGOING_REGEX" | wc -l`
deferred.value `(test -d deferred && find deferred -type f ) | wc -l`
maildrop.value `(test -d maildrop && find maildrop -type f ) | wc -l`
incoming.value `syslogXmins $MAILLOG | grep "$INCOMING_REGEX" | wc -l`
corrupt.value `(test -d corrupt && find corrupt -type f ) | wc -l`
hold.value `( test -d hold && find hold -type f ) | wc -l`
EOF