#!/usr/bin/env ruby

=begin

mongrel_process_memory - A munin plugin to monitor memory size of
                         each individual mongrel process
Copyright (C) 2007 Ben VandenBos and Avvo, Inc.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2
as published by the Free Software Foundation.

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, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

Author: Ben VandenBos
Contributors: Adam Jacob (<adam@hjksolutions.com>)
              Ryan Woodrum

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

=end


module Munin
  class MongrelProcessMemory
    def run
      h = get_pids()
      ps_output = ""
      # I have no doubt that this is a terrible way of doing this.
      h.each do |k, v|
        ps_output = ps_output + `ps --no-heading l #{k}`
      end

      if ps_output
        port_list = Hash.new
        ps_output.each_line do |l|
          if l =~ /-p (\d+)/
            port = $1
            l_ary = l.split(/\s+/)
            if l_ary.length > 6
              port_list[port] = l_ary[7].to_i * 1024
            end
          end
        end
        port_list.sort.each do |port|
          puts "mongrel_#{port[0]}.value #{port[1]}"
        end

      end
    end

    def get_pids
      h = Hash.new
      pids = []
      pids = `pgrep mongrel_rails`
      pids.each { |p|
        l = `ps #{p}`
        l =~ /-p (\d+)/
        h[p] = $1
      }
      h
    end

    def autoconf
      pids.length > 0
    end
  end
end

mpm = Munin::MongrelProcessMemory.new

case ARGV[0]
when "config"
  puts "graph_title Mongrel Memory"
  puts "graph_vlabel RSS"
  puts "graph_category memory"
  puts "graph_args --base 1024 -l 0"
  puts "graph_scale yes"
  puts "graph_info Tracks the size of individual mongrel processes"
  mpm.get_pids.values.sort.each do |port|
    puts "mongrel_#{port}.label mongrel_#{port}"
    puts "mongrel_#{port}.info Process memory"
    puts "mongrel_#{port}.type GAUGE"
    puts "mongrel_#{port}.min 0"
  end
when "autoconf"
  if mpm.autoconf
    puts "yes"
    exit 0
  end
  puts "no"
  exit 0
else
  mpm.run
end