Chef:Install windows_feature with guard clause not_if - ruby

Question

I'm using Chef 12.4 and using chef-client in local mode. I'm trying to install windows features and detect their current status before I do the installation, or removal. The reason for using the not if, is because when using DISM it takes for ever to check the current state.
Currently I have a server that takes 45 minutes to build and then 20 minutes to run chef even when there is nothing to do.
I used the following Powershell script 'service-check.ps1' to output the status of the package, this is put in place by the recipe itself:
$content = Get-Content .\features.txt
$feature = $args[0]
function grep($f) {
foreach($_ in $content){
$data = $_.split("|")
%{if($($data[0]) -match $f) {return "$($data[1])"}}
}
}
grep $feature
The recipe I'm using writes the 'features.txt' file to the location where Chef is being run, by querying dism for the current features and their status. The recipe file is as follows:
#Check the features and their current state
powershell_script 'installed_features' do
code <<-EOH
dism /online /get-features /format:table > c://chef//features.txt
EOH
end
cookbook_file 'C:\Scripts\service-check.ps1' do
source 'service-check.ps1'
end
windows_feature 'TelnetClient' do
action :remove
only_if {
status = powershell_out("Powershell -f C:\\scripts\\service-check.ps1 TelnetClient").stdout.chop
Disabled != status
}
end
I have tried many different formats in the only_if {} segment, however none of them have worked. I used the example that is here:
http://pdalinis.blogspot.co.uk/2013/09/chef-using-powershell-as-conditional.html
The output I get is:
* windows_feature[TelnetClient] action remove
================================================================================
Error executing action `remove` on resource 'windows_feature[TelnetClient]'
================================================================================
NameError
---------
uninitialized constant Chef::Recipe::Disabled
Resource Declaration:
---------------------
# In C:/chef/local-mode-cache/cache/cookbooks/tester/recipes/default.rb
12: windows_feature 'TelnetClient' do
13: action :remove
14: only_if {
15: status = powershell_out("Powershell -f C:\\scripts\\service-check.ps1 TelnetClient").stdout.chop
16: Disabled != status
17: }
18: end
Compiled Resource:
------------------
# Declared in C:/chef/local-mode-cache/cache/cookbooks/tester/recipes/default.rb:12:in `from_file'
windows_feature("TelnetClient") do
provider LWRP provider windows_feature_dism from cookbook windows
action [:remove]
retries 0
retry_delay 2
default_guard_interpreter :default
declared_type :windows_feature
cookbook_name "tester"
recipe_name "default"
only_if { #code block }
end
I'm a novice at Chef, Ruby and Powershell. I'm assuming that the only_if or not_if are expecting a true or false result, however this seems to be appending the written status that I've added the check against (in this script, disabled).
I have checked the powershell script, it does indeed output Enabed / Disabled depending on the status.
My questions are:
Is it possible to use windows_feature and powershell_out in this way, according to the example it's using powershell_script, but I'd rather use the windows_feature specification to install features.
If it is possible, what am I doing wrong? I have a feeling it might be the output of the script as it seems to insert a space:
" Enabled"
" Disabled"
If it isn't possible, is there another way to do it?
I'd be very grateful for any assistance.
Thank you.

Answer 1

is it possible you just need to quote "Disabled"? Otherwise Ruby is trying to figure out what it is, but doesn't know about any variable or class with that name.