From 2a72cc32dda5c1311c05d1357bd539faa87162d6 Mon Sep 17 00:00:00 2001
From: Steve Schnepp <steve.schnepp@pwkf.org>
Date: Thu, 5 Sep 2013 00:24:19 +0200
Subject: [PATCH] dovecot: Use DERIVE to avoid ugly computations

Using a timed grep with a state computation is usually mostly wrong. The DERIVE
field type is specifically designed for that very purpose.

Closes #264
---
 plugins/mail/dovecot | 83 +++++++++++++++-----------------------------
 1 file changed, 28 insertions(+), 55 deletions(-)

diff --git a/plugins/mail/dovecot b/plugins/mail/dovecot
index b3b80ed0..0f6b925d 100755
--- a/plugins/mail/dovecot
+++ b/plugins/mail/dovecot
@@ -7,6 +7,7 @@
 # http://developer.gauner.org/munin/
 # Contributions by:
 # - Stephane Enten <tuf@delyth.net>
+# - Steve Schnepp <steve.schnepp@pwkf.org>
 # 
 # Parameters understood:
 #
@@ -28,7 +29,6 @@
 ######################
 # Configuration
 ######################
-STAT_FILE=${STAT_FILE:-/var/lib/munin-node/plugin-state/root/plugin-dovecot.state}
 EXPR_BIN=/usr/bin/expr
 LOGFILE=${logfile:-/var/log/mail.log}
 ######################
@@ -43,37 +43,27 @@ if [ "$1" = "config" ]; then
 	echo 'graph_category Mail'
 	echo 'graph_args --base 1000 -l 0'
 	echo 'graph_vlabel Login Counters'
-	echo 'login_total.label Total Logins'
-	echo 'login_tls.label TLS Logins'
-	echo 'login_ssl.label SSL Logins'
-	echo 'login_imap.label IMAP Logins'
-	echo 'login_pop3.label POP3 Logins'
+
+	for t in Total TLS SSL IMAP POP3
+	do
+		field=$(echo $t | tr '[:upper:]' '[:lower:]')
+		echo "login_$field.label $t Logins"
+		echo "login_$field.type DERIVE"
+		echo "login_$field.min 0"
+	done
+
 	echo 'connected.label Connected Users'
+
 	exit 0
 fi
 
-#############################
-# Initialization
-#############################
-if [ ! -r $STAT_FILE ]; then
-	echo "TOTAL=0" > $STAT_FILE
-	echo "TLS=0" >> $STAT_FILE
-	echo "SSL=0" >> $STAT_FILE
-	echo "IMAP=0" >> $STAT_FILE
-	echo "POP3=0" >> $STAT_FILE
-fi
-#############################
-
-
 ######################
 # Total Logins
 ######################
 echo -en "login_total.value "
-NEW_TOTAL=$(egrep '[dovecot]?.*Login' $LOGFILE | grep "`date '+%b %e'`" | sort | wc -l)
-OLD_TOTAL=$(grep TOTAL $STAT_FILE | cut -f2 -d '=')
-TOTAL=$($EXPR_BIN $NEW_TOTAL - $OLD_TOTAL)
-if [ $TOTAL -gt 0 ]; then
-	echo "$TOTAL"
+VALUE=$(egrep '[dovecot]?.*Login' $LOGFILE | sort | wc -l)
+if [ ! -z "$VALUE" ]; then
+	echo "$VALUE"
 else
 	echo "0"
 fi
@@ -83,8 +73,8 @@ echo -n
 ######################
 DISCONNECTS=$(egrep '[dovecot]?.*Disconnected' $LOGFILE | sort | wc -l)
 CONNECTS=$(egrep '[dovecot]?.*Login' $LOGFILE | sort | wc -l)
-DISCON=$($EXPR_BIN $CONNECTS - $DISCONNECTS)
-if [ $DISCON -lt 0 ]; then
+VALUE=$($EXPR_BIN $CONNECTS - $DISCONNECTS)
+if [ -z "$DISCON" ] || [ "$DISCON" -lt 0 ]; then
 	DISCON=0
 fi
 echo -en "connected.value "
@@ -94,11 +84,9 @@ echo -n
 # TLS Logins
 ######################
 echo -en "login_tls.value "
-NEW_TLS=$(egrep '[dovecot]?.*Login.*TLS' $LOGFILE | grep "`date '+%b %e'`" | sort | wc -l)
-OLD_TLS=$(grep TLS $STAT_FILE | cut -f2 -d '=')
-TLS=$($EXPR_BIN $NEW_TLS - $OLD_TLS)
-if [ $TLS -gt 0 ]; then
-	echo "$TLS"
+VALUE=$(egrep '[dovecot]?.*Login.*TLS' $LOGFILE | sort | wc -l)
+if [ ! -z "$VALUE" ]; then
+        echo "$VALUE"
 else
 	echo "0"
 fi
@@ -107,11 +95,9 @@ echo -n
 # SSL Logins
 ######################
 echo -en "login_ssl.value "
-NEW_SSL=$(egrep '[dovecot]?.*Login.*SSL' $LOGFILE | grep "`date '+%b %e'`" | sort | wc -l)
-OLD_SSL=$(grep SSL $STAT_FILE | cut -f2 -d '=')
-SSL=$($EXPR_BIN $NEW_SSL - $OLD_SSL)
-if [ $SSL -gt 0 ]; then
-	echo "$SSL"
+VALUE=$(egrep '[dovecot]?.*Login.*SSL' $LOGFILE | sort | wc -l)
+if [ ! -z "$VALUE" ]; then
+        echo "$VALUE"
 else
 	echo "0"
 fi
@@ -120,11 +106,9 @@ echo -n
 # IMAP Logins
 ######################
 echo -en "login_imap.value "
-NEW_IMAP=$(egrep '[dovecot]?.*imap.*Login' $LOGFILE | grep "`date '+%b %e'`" | sort | wc -l)
-OLD_IMAP=$(grep IMAP $STAT_FILE | cut -f2 -d '=')
-IMAP=$($EXPR_BIN $NEW_IMAP - $OLD_IMAP)
-if [ $IMAP -gt 0 ]; then
-	echo "$IMAP"
+VALUE=$(egrep '[dovecot]?.*imap.*Login' $LOGFILE | sort | wc -l)
+if [ ! -z "$VALUE" ]; then
+        echo "$VALUE"
 else
 	echo "0"
 fi
@@ -133,21 +117,10 @@ echo -n
 # POP3 Logins
 ######################
 echo -en "login_pop3.value "
-NEW_POP3=$(egrep '[dovecot]?.*pop3.*Login' $LOGFILE | grep "`date '+%b %e'`" | sort | wc -l)
-OLD_POP3=$(grep POP3 $STAT_FILE | cut -f2 -d '=')
-POP3=$($EXPR_BIN $NEW_POP3 - $OLD_POP3)
-if [ $POP3 -gt 0 ]; then
-	echo "$POP3"
+VALUE=$(egrep '[dovecot]?.*pop3.*Login' $LOGFILE | sort | wc -l)
+if [ ! -z "$VALUE" ]; then
+        echo "$VALUE"
 else
 	echo "0"
 fi
 echo -n
-######################
-# Save the new values
-######################
-echo "TOTAL=$NEW_TOTAL" > $STAT_FILE
-echo "TLS=$NEW_TLS" >> $STAT_FILE
-echo "SSL=$NEW_SSL" >> $STAT_FILE 
-echo "IMAP=$NEW_IMAP" >> $STAT_FILE
-echo "POP3=$NEW_POP3" >> $STAT_FILE
-