Help an rspec newb

gistfile1.rb

WTF am I doing wrong here?

mdadm ohai plugin:

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

  def create_raid_device_mash(stdout)
    device_mash = Mash.new
    device_mash[:device_counts] = Mash.new
    stdout.each_line 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.exist?('/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
          cmd = "mdadm --detail /dev/#{device}"
          status, stdout, stderr = run_command(:command => cmd)

          # 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(stdout) if status == 0
        end
      end
    end
  end
end



output:
"mdadm": {
    "md0": {
      "device_counts": {
        "raid": 6,
        "total": 6,
        "active": 6,
        "working": 6,
        "failed": 0,
        "spare": 0
      },
      "version": 1.2,
      "level": 10,
      "size": 2794.16,
      "state": "clean"
    }
  }
  
  
spec:
require File.expand_path(File.dirname(__FILE__) + '/../../../spec_helper.rb')

@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

describe Ohai::System, "Linux Mdadm Plugin" do
  before(:each) do
    @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


Painful failure where I'm probably missing something horribly obvious:

  1) Ohai::System Linux Mdadm Plugin gathering Mdadm information via /proc/mdstat and mdadm --detail should have a device count of 6 on md0
     Failure/Error: @plugin[:mdadm][:md0][:device_counts][:raid] == 6
     NoMethodError:
       undefined method `[]' for nil:NilClass
     # ./spec/unit/plugins/linux/mdadm_spec.rb:77:in `block (3 levels) in <top (required)>'

See the fork: https://gist.github.com/btm/5fb6b9011f7a3eb3a7b2

I think the initial error you're getting comes from using File.exist? but stubbing File.exists?

Then you're using run_command in the plugin but stubbing shell_out, just use shell_out in the plugin.