gistfile1.rb

#!/usr/bin/env oo-ruby

require 'openshift-origin-node'
require 'strscan'

gears = %w(533c34e04b85e4913e000009
533c38384b85e4913e000031
533c38294b85e4a2d6000015
533c38384b85e49c3c000003
533c38024b85e4913e00001d
533c38024b85e4a2d6000001)

class CggetMetricsParser
  def initialize
    @gear = nil
    @saved = ''
    @group = nil
  end

  # Processes output from cgget and sends each metric to Syslog
  #
  # The ouput has the following sequences/types of data
  #
  # HEADER
  # /openshift/$gear_uuid:
  #
  # SINGLE KEY-VALUE PAIR
  # cpu.rt_period_us: 1000000
  #
  # PARENT-CHILD KEY-VALUE PAIRS
  # cpu.stat: nr_periods 6266
  #     nr_throttled 0
  #     throttled_time 0
  #
  # SEPARATOR
  # <a blank line separates gears>
  #
  # This method will take each chunk of output from cgget, keep track
  # of what it is in the middle of processing, and emit individual
  # metrics to Syslog as it sees them.
  #
  def <<(data)
    scanner = StringScanner.new(data)
    loop do
      # look for a newline
      line = scanner.scan_until(/\n/)
      if line.nil?
        # no newline, save what we got and wait for the next call to <<
        @saved += scanner.rest
        break
      end

      # got a full line
      line = @saved + line

      # clear out anything we might have previously saved
      @saved = ''

      # strip off any newline
      line.chomp!

      # HEADER check
      # see if we're looking for the gear
        if @gear.nil?
          # line must be a gear of the form /openshift/$uuid
          @gear = line[0..-2].gsub('/openshift/', '')
        
          # there may be more data to process, so move on to the next
          # loop iteration
          next
        end
        
        # SEPARATOR check
        # see if we've reached the end of data for the current gear
        # i.e. a blank line
        if line =~ /^\s*$/
          # clear out the gear
          @gear = nil
        
          # there may be more data to process, so move on to the next
          # loop iteration
          next
        end
        
        # CHILD check
        # currently in a group
        if line =~ /^\s/
          key, value = line.split
          publish(key, value)
        else
          # no longer in a group if we previously were
          @group = nil
        
          key, value = line.split(':')
          value.strip!
        
          if key == 'cpuacct.usage_percpu'
            # got a line of the form "cpuacct.usage_percpu: 3180064217 3240110361"
            value.split.each_with_index do |usage, i|
              publish("#{key}.#{i}", usage)
            end
          elsif value =~ /\s/
            # got a line of the form "cpu.stat: nr_periods 6266"
            # so we're now in a group
            @group = "#{key}."
            key, value = value.split
            publish(key, value)
          else
            # not in a group, got a line of the form "cpu.rt_runtime_us: 0"
            publish(key, value)
          end
        end
      end
    end

    def publish(key, value)
      Syslog.info("type=metric app=#{@apps[@gear]} gear=#{@gear} #{@group}#{key}=#{value}"
    end
  end
end

p = CggetMetricsParser.new
OpenShift::Runtime::Utils.oo_spawn("cgget -a #{gears.map {|g| "/openshift/#{g}"}.join(' ')}", out: p)