pads_stats

#!/usr/bin/perl
# vim: set filetype=perl sw=4 tabstop=4 expandtab smartindent: #

=head1 NAME

  pads_stats_- plugin to get stats from etherpad lite (must have the ep_pads_stats plugin)

=head1 AUTHOR AND COPYRIGHT

  Copyright 2015 Luc Didry <luc AT didry.org>

=head1 HOWTO CONFIGURE AND USE :

=over

=item - /etc/munin/plugin-conf.d/pads_stats

     [pads_stats]
     env.urls https://pad.example.org https://pad.whatever.org

=item - env.urls

  This is the URLs of the etherpad instances to get stats from (without trailing slash)

  You can specify the port, or a login and a password for HTTP authentication

     https://login:password@pad.example.org:9001

=item - /etc/munin/plugins

     ln -s pads_stats /etc/munin/plugins/pads_stats

=item - restart Munin node

     service munin-node restart

=back

=head1 DEPENDENCIES

  You will need the Perl distribution Mojolicious

  Although it is certainly available in your GNU/Linux packages, it recommended to install it trough the cpan command:

     cpan Mojolicious

  If you want to monitor secured etherpad instances (HTTPS), you need IO::Socket::SSL (may require libssl-dev to install)

     cpan IO::Socket::SSL

=head1 LICENSE

  This program is free software: you can redistribute it and/or modify it under
  the terms of the GNU General Public License as published by the Free Software
  Foundation, either version 3 of the License, or any later version.

  This program is distributed in the hope that it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License along with
  this program.  If not, see <http://www.gnu.org/licenses/>.

=cut

use warnings;
use strict;
use Munin::Plugin;
use Mojo::UserAgent;
use Mojo::JSON qw(decode_json);

my $PLUGIN_NAME = 'pads_stats';

munin_exit_fail() unless (defined($ENV{urls}));

my @urls = split(' ', $ENV{urls});

##### config
if( (defined $ARGV[0]) && ($ARGV[0] eq 'config') ) {
    print "multigraph pads_stats\n";
    print "graph_title Pads Stats\n";
    print "graph_vlabel Number of pads\n";
    print "graph_args --lower-limit 0\n";
    print "graph_category etherpad\n";
    print "graph_total Total\n";
    print "graph_info This graph shows the count of pads across multiple Etherpad lite instance\n";
    my $i = 0;
    for my $url (@urls) {
        my $u    = Mojo::URL->new($url);
        my $host = $u->host;
        $host    =~ s/\./_/g;
        my $draw = ($i++) ? 'AREASTACK' : 'AREA';
        print "$host.label $host\n";
        print "$host.draw $draw\n";
    }
    for my $url (@urls) {
        my $u    = Mojo::URL->new($url);
        my $host = $u->host;
        $host    =~ s/\./_/g;
        print "multigraph pads_stats.$host\n";
        print "graph_title Pads Stats for ".$u->host."\n";
        print "graph_vlabel Number of pads on ".$u->host."\n";
        print "graph_args --lower-limit 0\n";
        print "graph_category etherpad\n";
        print "$host.label $host\n";
        print "$host.draw AREA\n";
    }
    munin_exit_done();
}

##### fetch
my $ua = Mojo::UserAgent->new();
my %cache;
for my $url (@urls) {
    $url   = $url.'/stats.json';
    my $u  = Mojo::URL->new($url);
    my $tx = $ua->get($url);
    if (my $res = $tx->success) {
        my $r = decode_json($res->body);
        my $host = $u->host;
        $host    =~ s/\./_/g;
        print $host, '.value ', $r->{padsCount}, "\n";
        $cache{$host} = $r->{padsCount};
    }
}
for my $url (@urls) {
    my $u  = Mojo::URL->new($url);
    my $host = $u->host;
    $host    =~ s/\./_/g;
    print "multigraph pads_stats.$host\n";
    print $host, '.value ', $cache{$host}, "\n";
}
munin_exit_done();

#
##
### INTERNALS FONCTIONS
###############################################################################
sub munin_exit_done {
    munin_exit(0);
} ## sub munin_exit_done

sub munin_exit_fail {
    munin_exit(1);
} ## sub munin_exit_fail

sub munin_exit {
    my $exitcode = shift;
    exit($exitcode) if(defined $exitcode);
    exit(1);
} ## sub munin_exit