From 3df80bd30020df6f4081fa09dc686336ef317226 Mon Sep 17 00:00:00 2001
From: Denis Zheleztsov <difrex@bingo-boom.ru>
Date: Fri, 17 Jul 2015 15:08:19 +0300
Subject: [PATCH] mailer handler update

---
 handlers/mailer.pl | 129 +++++++++++++++++++++++++++++++++------------
 1 file changed, 96 insertions(+), 33 deletions(-)

diff --git a/handlers/mailer.pl b/handlers/mailer.pl
index 60aa903..82d5d5f 100755
--- a/handlers/mailer.pl
+++ b/handlers/mailer.pl
@@ -4,49 +4,51 @@ use strict;
 use warnings;
 use JSON;
 
+use Data::Dumper;
+
 my $json = <>;
 
 my $message = decode_json($json);
 
 my $statuses = {
-	'2' => 'Critical',
-	'1' => 'Warning',
-	'0' => 'Ok'
+    '2' => 'Critical',
+    '1' => 'Warning',
+    '0' => 'Ok'
 };
 
-
 # Get client values
 my $client_name = $message->{client}->{name};
 my $client_addr = $message->{client}->{address};
-my $timestamp 	= localtime( $message->{client}->{timestamp} );
+my $timestamp   = localtime( $message->{client}->{timestamp} );
 
 # Get check information
-my $check_name 		= $message->{check}->{name};
-my $check_out 		= $message->{check}->{output};
-my $check_command	= $message->{check}->{command};
-my $check_interval	= $message->{check}->{interval};
-my $check_status 	= $statuses->{ $message->{check}->{status} };
-my @ch 			= $message->{check}->{history};
+my $check_name     = $message->{check}->{name};
+my $check_out      = $message->{check}->{output};
+my $check_command  = $message->{check}->{command};
+my $check_interval = $message->{check}->{interval};
+my $check_status   = $statuses->{ $message->{check}->{status} };
+my @ch             = $message->{check}->{history};
 my @check_history;
+
 foreach my $c (@ch) {
-	@check_history = @$c;
+    @check_history = @$c;
 }
 
 # Count history
-my $ok_count 	= 0;
-my $warn_count 	= 0;
-my $crit_count 	= 0;
-my $total = @check_history;
+my $ok_count   = 0;
+my $warn_count = 0;
+my $crit_count = 0;
+my $total      = @check_history;
 foreach my $stat (@check_history) {
-	if ( $stat eq '2' ) {
-		$crit_count++;
-	}
-	elsif ( $stat eq '1' ) {
-		$warn_count++;
-	}
-	else {
-		$ok_count++;
-	}
+    if ( $stat eq '2' ) {
+        $crit_count++;
+    }
+    elsif ( $stat eq '1' ) {
+        $warn_count++;
+    }
+    else {
+        $ok_count++;
+    }
 }
 
 # Build mail body message
@@ -69,20 +71,81 @@ CRITICAL: $crit_count
 ";
 
 # Send email
-my $mail_cmd 	= 'mail';
-my $mail_subg 	= "$client_name with address $client_addr status: $check_status";
-my $mail_to 	= 'admins@example.com';
+my $mail_cmd = 'mail';
+my $mail_subg
+    = "$client_name with address $client_addr status: $check_status";
+my $mail_to = 'admins@example.com';
 
 # Make text file
-my $mail_file 	= '/tmp/'.$message->{client}->{timestamp}.'mail.txt';
+my $mail_file = '/tmp/' . $message->{client}->{timestamp} . 'mail.txt';
 open my $mail_fh, '>', $mail_file or die "$!\n";
 print $mail_fh $mail_body;
 close $mail_fh;
 
-# Send it now!
-`cat $mail_file | $mail_cmd -s "'$mail_subg'" $mail_to`;
+# Write current status to file
+sub write_status {
+    my ( $check_name, $status ) = @_;
+    my $check_run_file = '/etc/sensu/handlers/run/' . $check_name;
+
+    open my $run, '>', $check_run_file or die "Cannot open file: $!\n";
+    print $run $status;
+    close($run);
+}
+
+# Get previous status
+sub get_previous_status {
+    my ( $check_name, $status ) = @_;
+    my $check_run_file = '/etc/sensu/handlers/run/' . $check_name;
+
+    my $previous_check_status;
+    open my $run, '<', $check_run_file or warn "Cannot open file: $!\n";
+    if ($run) {
+        while (<$run>) {
+            $previous_check_status = $_;
+        }
+        close($run);
+
+        return $previous_check_status;
+    }
+
+    # New checks hack
+    else {
+        write_status( $check_name, $status );
+
+        return -1;
+    }
+}
+
+# Check status
+sub status_change {
+    my ($message) = @_;
+
+    my $check_name = $message->{check}->{name};
+
+    # Current check status
+    my $current_check_status = $message->{check}->{status};
+
+    # Get provious check status
+    my $previous_check_status
+        = get_previous_status( $check_name, $current_check_status );
+
+    if (   ( $previous_check_status == -1 )
+        or ( $previous_check_status eq $current_check_status ) )
+    {
+        return -1;
+    }
+    else {
+        return 0;
+    }
+
+}
+
+# Send it if status changed
+if ( status_change == 0 ) {
+
+    `cat $mail_file | $mail_cmd -v -s "'$mail_subg'" $mail_to`;
+}
 
 # Remove temp file
-my @rm_cmd = ('rm', '-f', $mail_file);
+my @rm_cmd = ( 'rm', '-f', $mail_file );
 system(@rm_cmd) == 0 or die "$!\n";
-