munin plugin for passenger (adapted for rvm)

passenger_status.rb

#!/usr/bin/env ruby

def output_config
  puts <<-END
graph_category App
graph_title passenger status
graph_vlabel count

sessions.label sessions
max.label max processes
running.label running processes
active.label active processes
END
  exit 0
end

def output_values
  status = `sudo /usr/local/bin/rvm-shell -c passenger-status`
  #or use the line bellow if not using rvm
  #status = `sudo /usr/bin/passenger-status`
  unless $?.success?
    $stderr.puts "failed executing passenger-status"
    exit 1
  end
  status =~ /max\s+=\s+(\d+)/
  puts "max.value #{$1}"

  status =~ /count\s+=\s+(\d+)/
  puts "running.value #{$1}"

  status =~ /active\s+=\s+(\d+)/
  puts "active.value #{$1}"

  total_sessions = 0
  status.scan(/Sessions: (\d+)/).flatten.each { |count| total_sessions += count.to_i }
  puts "sessions.value #{total_sessions}"
end

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