Get Temp Directory on Windows using Puppet

Question

I am trying to download a file using download_file module and want to save it to the temp directory. Is there a built in way to do this using Puppet without hard-coding it to C:\Windows\Temp.

download_file { "Download Flyway" :
    url                   => 'https://bintray.com/artifact/download/business/maven/flyway-commandline-3.2.1-windows-x64.zip',
    destination_directory => 'C:\Windows\Temp'
}

Answer 1

You can create a custom fact to provide that information (named something like modulename/lib/facter/module_temp_dir.rb):

Facter.add('module_temp_dir') do
  setcode do
    if Puppet::Util::Platform.windows?
        require 'win32/registry'

        value = nil
        begin
          # looking at current user may likely fail because it's likely going to be LocalSystem
          hive = Win32::Registry::HKEY_CURRENT_USER
          hive.open('Environment', Win32::Registry::KEY_READ | 0x100) do |reg|
            value = reg['TEMP']
          end
        rescue Win32::Registry::Error => e
          value = nil
        end

        if value.nil?
          begin
            hive = Win32::Registry::HKEY_LOCAL_MACHINE
            hive.open('SYSTEM\CurrentControlSet\Control\Session Manager\Environment', Win32::Registry::KEY_READ | 0x100) do |reg|
              value = reg['TEMP']
            end
          rescue Win32::Registry::Error => e
            value = nil
          end
        end
      end

      value
    end
  end
end

This approach is preferred over simply using ENV['TEMP'] as it is not subject to being tampered with like environment variables could be at runtime.

If you are not concerned with the value being tampered with and/or you may want to change it at runtime locally, you can instead do something like:

Facter.add('module_temp_dir') do
  setcode do
   ENV['TEMP']       
  end
end

As a followup for providing some/all of the environment variables automatically as facts, I've filed https://tickets.puppetlabs.com/browse/FACT-1346. It possible we can quickly move forward on providing more of the important system provided environment variables where to provide all of them, we would need the whitelisting feature that is currently stated as blocking that ticket (https://tickets.puppetlabs.com/browse/FACT-718).

Reference:

https://github.com/chocolatey/puppet-chocolatey/blob/master/lib/facter/choco_install_path.rb and https://github.com/chocolatey/puppet-chocolatey/blob/master/lib/puppet_x/chocolatey/chocolatey_install.rb