add megaraid_serial fact

lib/facter/megaraid_serial.rb

@@ -0,0 +1,13 @@
+Facter.add(:megaraid_serial) do
+  megacli = Facter.value(:megacli)
+
+  setcode do
+    unless megacli.nil?
+      output = Facter::Util::Resolution.exec("#{megacli} -Version -Ctrl -aALL")
+      next if output.nil?
+      m = output.match(/Serial No : (\S+)\s*$/)
+      next unless m.size == 2
+      m[1]
+    end
+  end
+end

spec/unit/facts/megaraid_serial_spec.rb

@@ -0,0 +1,31 @@
+require 'spec_helper'
+
+describe 'megaraid_serial', :type => :fact do
+  before(:each) { Facter.clear }
+
+  context 'megacli fact not set' do
+    it 'should return nil' do
+      Facter.fact(:megacli).stubs(:value).returns(nil)
+      Facter.fact(:megaraid_serial).value.should be_nil
+    end
+  end
+
+  context 'megacli fact is broken' do
+    it 'should return nil' do
+      Facter.fact(:megacli).stubs(:value).returns('foobar')
+      Facter.fact(:megaraid_serial).value.should be_nil
+    end
+  end
+
+  context 'megacli fact is working' do
+    it 'should get the version string' do
+      Facter.fact(:megacli).stubs(:value).returns('/usr/bin/MegaCli')
+      Facter::Util::Resolution.stubs(:exec).
+        with('/usr/bin/MegaCli -Version -Ctrl -aALL').
+        returns(File.read(fixtures('megacli', 'version-ctrl-aall-8.07.07')))
+      Facter.fact(:megaraid_serial).value.should == 'SV22925366'
+    end
+  end
+
+end
+