#!/usr/bin/env ruby
# put in /etc/munin/plugins and restart munin-node
# by Dan Manges, http://www.dcmanges.com/blog/rails-application-visualization-with-munin
# NOTE: you might need to add munin to allow passwordless sudo for passenger-memory-stats

require "English"

def output_config
  puts <<~CONFIG
    graph_args --base 1024 -l 0 --vertical-label bytes --upper-limit 4056231936
    graph_category passenger
    graph_title Passenger memory

    memory.label memory
  CONFIG
  exit 0
end

def output_values
  status = `/usr/sbin/passenger-memory-stats | tail -1`
  unless $CHILD_STATUS.success?
    warn "failed executing passenger-memory-stats"
    exit 1
  end
  status =~ /(\d+\.\d+)/
  puts "memory.value #{(Regexp.last_match[1].to_f * 1024 * 1024).round}"
end

if ARGV[0] == "config"
  output_config
else
  output_values
end