mdadm.rb

Ohai.plugin(:Mdadm) do
  provides 'mdadm'

  def create_raid_device_mash(stdout)
    device_mash = Mash.new
    device_mash[:device_counts] = Mash.new
    stdout.each do |line|
      case line
      when /Version\s+: ([0-9.]+)/
        device_mash[:version] = Regexp.last_match[1].to_f
      when /Raid Level\s+: raid([0-9]+)/
        device_mash[:level] = Regexp.last_match[1].to_i
      when /Array Size.*\(([0-9.]+)/
        device_mash[:size] = Regexp.last_match[1].to_f
      when /State\s+: ([a-z]+)/
        device_mash[:state] = Regexp.last_match[1]
      when /Total Devices\s+: ([0-9]+)/
        device_mash[:device_counts][:total] = Regexp.last_match[1].to_i
      when /Raid Devices\s+: ([0-9]+)/
        device_mash[:device_counts][:raid] = Regexp.last_match[1].to_i
      when /Working Devices\s+: ([0-9]+)/
        device_mash[:device_counts][:working] = Regexp.last_match[1].to_i
      when /Failed Devices\s+: ([0-9]+)/
        device_mash[:device_counts][:failed] = Regexp.last_match[1].to_i
      when /Active Devices\s+: ([0-9]+)/
        device_mash[:device_counts][:active] = Regexp.last_match[1].to_i
      when /Spare Devices\s+: ([0-9]+)/
        device_mash[:device_counts][:spare] = Regexp.last_match[1].to_i
      end
    end
    device_mash
  end

  collect_data(:linux) do
    # gather a list of all raid arrays
    if File.exists?('/proc/mdstat')
      devices = []
      File.open('/proc/mdstat').each do |line|
        devices << Regexp.last_match[1] if line =~ /(md[0-9]+)/
      end

      # create the mdadm mash and gather individual information if devices are present
      unless devices.empty?
        mdadm Mash.new
        devices.sort.each do |device|
          mdadm[device] = Mash.new

          # gather detailed information on the array
          so = shell_out("mdadm --detail /dev/#{device}")
          # if the mdadm command was sucessful pass stdout to create_raid_device_mash to grab the tidbits we want
          mdadm[device] = create_raid_device_mash(so.stdout.lines) if so.exitstatus == 0
        end
      end
    end
  end
end

mdadm_spec.rb

require File.expand_path(File.dirname(__FILE__) + '/../../../spec_helper.rb')

describe Ohai::System, "Linux Mdadm Plugin" do
  before(:each) do
    @md0 = <<-MD
    /dev/md0:
            Version : 1.2
      Creation Time : Thu Jan 30 03:11:40 2014
         Raid Level : raid10
         Array Size : 2929893888 (2794.16 GiB 3000.21 GB)
      Used Dev Size : 976631296 (931.39 GiB 1000.07 GB)
       Raid Devices : 6
      Total Devices : 6
        Persistence : Superblock is persistent

        Update Time : Tue May  6 23:30:32 2014
              State : clean
     Active Devices : 6
    Working Devices : 6
     Failed Devices : 0
      Spare Devices : 0

             Layout : near=2
         Chunk Size : 256K

               Name : host.therealtimsmith.com:3  (local to host host.therealtimsmith.com)
               UUID : 5ed74d5b:70bfe21d:8cd57792:c1e13d65
             Events : 155

        Number   Major   Minor   RaidDevice State
           0       8       32        0      active sync   /dev/sdc
           1       8       48        1      active sync   /dev/sdd
           2       8       64        2      active sync   /dev/sde
           3       8       80        3      active sync   /dev/sdf
           4       8       96        4      active sync   /dev/sdg
           5       8      112        5      active sync   /dev/sdh
MD

    @plugin = get_plugin("linux/mdadm")
    @plugin.stub(:collect_os).and_return(:linux)
    @double_file = double("/proc/mdstat")
    @double_file.stub(:each).
    and_yield("Personalities : [raid1] [raid6] [raid5] [raid4] [linear] [multipath] [raid0] [raid10]").
    and_yield("md0 : active raid10 sdh[5] sdg[4] sdf[3] sde[2] sdd[1] sdc[0]").
    and_yield("      2929893888 blocks super 1.2 256K chunks 2 near-copies [6/6] [UUUUUU]")
    File.stub(:open).with("/proc/mdstat").and_return(@double_file)
    File.stub(:exists?).with("/proc/mdstat").and_return(true)
    @plugin.stub(:shell_out).with("mdadm --detail /dev/md0").and_return(mock_shell_out(0, @md0, ""))
  end

  describe "gathering Mdadm information via /proc/mdstat and mdadm --detail" do

    it "should not raise an error" do
      lambda { @plugin.run }.should_not raise_error
    end

    it "should have a device count of 6 on md0" do
      @plugin.run
      @plugin[:mdadm][:md0][:device_counts][:raid].should be 6
    end
  end
end