#! /usr/bin/env ruby
#
# ceph-osd-metrics
#
# DESCRIPTION:
#   #YELLOW
#
# OUTPUT:
#   plain text
#
# PLATFORMS:
#   Linux
#
# DEPENDENCIES:
#   gem: sensu-plugin
#   gem: json
#   ceph client
#
# USAGE:
#   #YELLOW
#
# NOTES:
#   Dumps performance metrics from Ceph OSD admin socket into graphite-
#   friendly format. It is up to the implementer to create the admin
#   socket(s) and to handle the necessary permissions for sensu to access
#   (sudo, etc.). In the default configuration, admin sockets are expected
#   to reside in /var/run/ceph with a file format of ceph-osd.*.asok.
#
#   If a different file search pattern is specificied, it is expected to
#   have exactly one '*' wildcard denoting the OSD number.
#
# LICENSE:
#   Copyright 2013 Cloudapt, LLC
#   Brian Clark <brian.clark@cloudapt.com> and
#   Mike Dawson <mike.dawson@cloudapt.com>
#   Released under the same terms as Sensu (the MIT license); see LICENSE
#   for details.
#

require 'sensu-plugin/metric/cli'
require 'json'
require 'English'

#
# Ceph Osd Metrics
#
class CephOsdMetrics < Sensu::Plugin::Metric::CLI::Graphite
  option :scheme,
         description: 'Metric naming scheme, text prepended to .$parent.$child',
         long: '--scheme SCHEME',
         default: 'ceph.osd'

  option :pattern,
         description: 'Search pattern for sockets (/var/run/ceph/ceph-osd.*.asok)',
         short: '-p',
         long: '--pattern',
         default: '/var/run/ceph/ceph-osd.*.asok'

  def output_data(h, leader)
    h.each_pair do |key, val|
      if val.is_a?(Hash)
        val.each do |k, v|
          output "#{config[:scheme]}.#{leader}.#{key}_#{k}", v
        end
      else
        output "#{config[:scheme]}.#{leader}.#{key}", val
      end
    end
  end

  def run # rubocop:disable all
    # #YELLOW
    Dir.glob(config[:pattern]).each do |socket| # rubocop:disable Style/Next
      data = `ceph --admin-daemon #{socket} perf dump`
      if $CHILD_STATUS.exitstatus == 0
        # Left side of wildcard
        strip1 = config[:pattern].match(/^.*\*/).to_s.gsub(/\*/, '')
        # Right side of wildcard
        strip2 = config[:pattern].match(/\*.*$/).to_s.gsub(/\*/, '')
        osd_num = socket.gsub(strip1, '').gsub(strip2, '')
        JSON.parse(data).each do |k, v|
          k = k.gsub(/\/$/, '').gsub(/\//, '_')
          output_data(v, "#{osd_num}.#{k}")
        end
      end
    end
    ok
  end
end