New Resource: Chocolatey Package (#2793)

* Adds chocolatey package resource
* Adds docs for chocolatey_package resource
* Differentiate chocolatey package from windows feature

Suggested by @frezbo

Signed-off-by: David Alexander <opensource@thelonelyghost.com>

docs/resources/chocolatey_package.md.erb

@@ -0,0 +1,58 @@
+---
+title: About the chocolatey_package Resource
+platform: windows
+---
+
+# chocolatey_package
+
+Use the `chocolatey_package` InSpec audit resource to test if the named [Chocolatey](https://chocolatey.org/) package and/or package version is installed on the system.
+
+<br>
+
+## Syntax
+
+A `chocolatey_package` resource block declares the name of a Chocolatey package to be tested:
+
+    describe chocolatey_package('name') do
+      it { should be_installed }
+    end
+
+where
+
+* `('name')` must specify the (case-sensitive) name of a package, such as `'nssm'`
+* `be_installed` is a valid matcher for this resource
+
+<br>
+
+## Examples
+
+The following examples show how to use this InSpec audit resource
+
+### Test if NSSM version 2.1.0 is installed
+
+    describe chocolatey_package('nssm') do
+      it { should be_installed }
+      its('version') { should eq '2.1.0' }
+    end
+
+## Matchers
+
+For a full list of available matchers, please visit our [matchers page](https://www.inspec.io/docs/reference/matchers).
+
+### be_installed
+
+The `be_installed` matcher tests if the named package is installed at all.
+
+    it { should be_installed }
+
+### version
+
+The `version` matcher tests if the named package version is on the system:
+
+    its('version') { should eq '2.1.0' }
+
+You can also use the `cmp OPERATOR` matcher to perform comparisons using the version attribute:
+
+    its('version') { should cmp >= '1.93.4-13debug84' }
+
+`cmp` understands version numbers using Gem::Version, and can use the operators `==, <, <=, >=, and >`. It will compare versions by each segment, not as a string - so '7.4' is smaller than '7.30', for example.

lib/inspec/resource.rb

@@ -95,6 +95,7 @@ require 'resources/auditd_conf'
 require 'resources/bash'
 require 'resources/bond'
 require 'resources/bridge'
+require 'resources/chocolatey_package'
 require 'resources/command'
 require 'resources/cran'
 require 'resources/cpan'

lib/resources/chocolatey_package.rb

@@ -0,0 +1,78 @@
+# encoding: utf-8
+# frozen_string_literal: true
+
+# Check for Chocolatey packages to be installed
+module Inspec::Resources
+  class ChocoPkg < Inspec.resource(1)
+    name 'chocolatey_package'
+    supports platform: 'windows'
+    desc 'Use the chocolatey_package Inspec audit resource to test if the named package and/or package version is installed on the system.'
+    example <<-EOH
+      describe chocolatey_package('git') do
+        it { should be_installed }
+        its('version') { should eq '2.15.1' }
+      end
+    EOH
+
+    attr_reader :package_name
+
+    def initialize(package_name, _opts = {})
+      raise 'Chocolatey is not installed' unless inspec.command('choco').exist?
+      @package_name = package_name
+      @cache = base_data.update(generate_cache)
+    end
+
+    def installed?
+      @cache[:installed]
+    end
+
+    def info
+      @cache.dup
+    end
+
+    def respond_to_missing?(method_name, *)
+      @cache.key?(method_name) || super
+    end
+
+    def method_missing(method_name, *args, &block)
+      if @cache.key?(method_name)
+        @cache.fetch(method_name)
+      else
+        super
+      end
+    end
+
+    def to_s
+      "Chocolatey package #{package_name}"
+    end
+
+    private
+
+    def base_data
+      {
+        name: package_name,
+        version: nil,
+        installed: false,
+        type: 'chocolatey',
+      }
+    end
+
+    def generate_cache
+      command = <<-EOH
+      (choco list --local-only --exact --include-programs --limit-output '#{package_name.gsub("'", "\`'")}') -Replace "\\|", "=" | ConvertFrom-StringData | ConvertTo-JSON
+      EOH
+
+      cmd = inspec.powershell(command.strip)
+
+      return {} if cmd.exit_status != 0 || cmd.stdout.strip.empty?
+      out = JSON.parse(cmd.stdout)
+
+      return {
+        version: out.fetch(package_name),
+        installed: true,
+      }
+    rescue JSON::ParserError, KeyError
+      return {}
+    end
+  end
+end

test/helper.rb

@@ -261,6 +261,10 @@ class MockLoader
       '/test/path/pip show django' => cmd.call('pip-show-non-standard-django'),
       "Get-Package -Name 'Mozilla Firefox' | ConvertTo-Json" => cmd.call('get-package-firefox'),
       "Get-Package -Name 'Ruby 2.1.6-p336-x64' | ConvertTo-Json" => cmd.call('get-package-ruby'),
+      'Get-Command "choco"' => empty.call,
+      'bash -c \'type "choco"\'' => cmd_exit_1.call,
+      '(choco list --local-only --exact --include-programs --limit-output \'nssm\') -Replace "\|", "=" | ConvertFrom-StringData | ConvertTo-JSON' => cmd.call('choco-list-nssm'),
+      '(choco list --local-only --exact --include-programs --limit-output \'git\') -Replace "\|", "=" | ConvertFrom-StringData | ConvertTo-JSON' => empty.call,
       "New-Object -Type PSObject | Add-Member -MemberType NoteProperty -Name Service -Value (Get-Service -Name 'dhcp'| Select-Object -Property Name, DisplayName, Status) -PassThru | Add-Member -MemberType NoteProperty -Name WMI -Value (Get-WmiObject -Class Win32_Service | Where-Object {$_.Name -eq 'dhcp' -or $_.DisplayName -eq 'dhcp'} | Select-Object -Property StartMode) -PassThru | ConvertTo-Json" => cmd.call('get-service-dhcp'),
       "New-Object -Type PSObject | Add-Member -MemberType NoteProperty -Name Pip -Value (Invoke-Command -ScriptBlock {where.exe pip}) -PassThru | Add-Member -MemberType NoteProperty -Name Python -Value (Invoke-Command -ScriptBlock {where.exe python}) -PassThru | ConvertTo-Json" => cmd.call('get-windows-pip-package'),
       "Get-WindowsFeature | Where-Object {$_.Name -eq 'dhcp' -or $_.DisplayName -eq 'dhcp'} | Select-Object -Property Name,DisplayName,Description,Installed,InstallState | ConvertTo-Json" => cmd.call('get-windows-feature'),

test/unit/mock/cmd/choco-list-nssm

@@ -0,0 +1,3 @@
+{
+    "nssm":  "2.24.101"
+}

test/unit/resources/chocolatey_package_test.rb

@@ -0,0 +1,27 @@
+# encoding: utf-8
+# author: David Alexander <opensource@thelonelyghost.com>
+
+require 'helper'
+require 'inspec/resource'
+
+def skip(*args)
+  # noop
+end
+
+describe 'Inspec::Resources::ChocoPkg' do
+  it 'can parse output from `choco` when package is installed' do
+    pkg = { name: 'git', installed: false, version: nil, type: 'chocolatey' }
+    resource = MockLoader.new(:windows).load_resource('chocolatey_package', 'git')
+    _(resource.installed?).must_equal pkg[:installed]
+    _(resource.version).must_equal pkg[:version]
+    _(resource.info).must_equal pkg
+  end
+
+  it 'can parse output from `choco` when package not installed' do
+    pkg = { name: 'nssm', installed: true, version: '2.24.101', type: 'chocolatey' }
+    resource = MockLoader.new(:windows).load_resource('chocolatey_package', 'nssm')
+    _(resource.installed?).must_equal pkg[:installed]
+    _(resource.version).must_equal pkg[:version]
+    _(resource.info).must_equal pkg
+  end
+end