New option python_manage to collectd::plugin::python

Particularly on Ubuntu it nescesary to install python explicitly
otherwise the directory `/usr/local/lib/python2.7` does
not exist. Collectd itself only requires python-lib.

The option defaults to `false` and a python package is not
maintained.

README.md

@@ -1407,6 +1407,8 @@ class { 'collectd::plugin::protocols':
 ```
 
 #### Class: `collectd::plugin::python`
+The plugin uses a fact `python_dir` to find the python load path for modules.
+python must be installed for the this fact to give a non-default value.
 
 * `modulepaths` is an array of paths where will be Collectd looking for Python
   modules, Puppet will ensure that each of specified directories exists and it
@@ -1425,6 +1427,10 @@ class { 'collectd::plugin::protocols':
   collectd with the name of the exception and the message (default: `false`)
 * `conf_name` name of the file that will contain the python module configuration
   (default: `python-config.conf`)
+* `python_manage` Should a python package be installed. (default `false`) Python
+  is needed for the fact `python_dir` to function.
+* `python_package` Name of python package to install. (default `python`)
+* `python_package_ensure` Ensure state of python package to install. (default `present`)
 
  See [collectd-python documentation](https://collectd.org/documentation/manpages/collectd-python.5.shtml)
  for more details.

manifests/plugin/python.pp

@@ -1,19 +1,22 @@
 # See http://collectd.org/documentation/manpages/collectd.conf.5.shtml#plugin_python
 class collectd::plugin::python (
   # Python 2 defaults to 'ascii' and Python 3 to 'utf-8'
-  $encoding            = undef,
-  $ensure              = 'present',
+  $encoding              = undef,
+  $ensure                = 'present',
   # Unlike most other plugins, this one should set "Globals true". This will cause collectd
   # to export the name of all objects in the Python interpreter for all plugins to see.
-  Boolean $globals     = true,
-  Boolean $interactive = false,
-  $interval            = undef,
-  Boolean $logtraces   = false,
-  $manage_package      = undef,
-  Array $modulepaths   = [],
-  Hash $modules        = {},
-  $order               = '10',
-  $conf_name           = 'python-config.conf',
+  Boolean $globals              = true,
+  Boolean $interactive          = false,
+  $interval                     = undef,
+  Boolean $logtraces            = false,
+  $manage_package               = undef,
+  Array $modulepaths            = [],
+  Hash $modules                 = {},
+  $order                        = '10',
+  $conf_name                    = 'python-config.conf',
+  Boolean $manage_python        = false,
+  String $python_package        = 'python',
+  String $python_package_ensure = 'present',
 ) {
 
   include ::collectd
@@ -47,6 +50,13 @@
     globals  => $globals,
   }
 
+  if $manage_python {
+    ensure_packages([$python_package], { ensure => $python_package_ensure })
+    $_module_dir_require = [Package[$collectd::package_name],Package[$python_package]]
+  } else {
+    $_module_dir_require = Package[$collectd::package_name]
+  }
+
   $ensure_modulepath = $ensure ? {
     'absent' => $ensure,
     default  => 'directory',
@@ -60,7 +70,7 @@
       'purge'   => $::collectd::purge_config,
       'force'   => true,
       'group'   => $collectd::config_group,
-      'require' => Package[$collectd::package_name]
+      'require' => $_module_dir_require,
     }
   )
 

spec/classes/collectd_plugin_python_spec.rb

@@ -11,6 +11,9 @@
 
       context ':ensure => present' do
         context ':ensure => present and default parameters' do
+          it 'install python package' do
+            is_expected.not_to contain_package('python')
+          end
           it 'ensures that $modulepaths exits' do
             is_expected.to contain_file('/usr/local/lib/python2.7/dist-packages').with(ensure: 'directory')
           end
@@ -48,6 +51,37 @@
             )
           end
         end
+        context ':ensure => present and python package specified' do
+          let :params do
+            {
+              python_package: 'mypython',
+              python_package_ensure: '1.2.3',
+              manage_python: true
+            }
+          end
+
+          it 'install specified python package' do
+            is_expected.to contain_package('mypython').with(ensure: '1.2.3')
+          end
+        end
+
+        context ':ensure => present, moduledirs and manage_python false' do
+          let :params do
+            {
+              modulepaths: ['/tmp/', '/data/'],
+              manage_python: false
+            }
+          end
+
+          it 'install specified python package' do
+            is_expected.not_to contain_package('python')
+          end
+          it 'will ensure one directory is here here' do
+            is_expected.to contain_file('/tmp/').with(
+              require: 'Package[collectd]'
+            )
+          end
+        end
 
         context ':ensure => present and multiple $modulepaths' do
           let :params do
@@ -57,7 +91,9 @@
           end
 
           it 'will ensure the two directories are here' do
-            is_expected.to contain_file('/tmp/')
+            is_expected.to contain_file('/tmp/').with(
+              require: 'Package[collectd]'
+            )
             is_expected.to contain_file('/data/')
           end
           it 'will set two modulepath in the module conf' do

spec/spec_helper_acceptance.rb

@@ -15,6 +15,7 @@
     # Install module and dependencies
     puppet_module_install(source: proj_root, module_name: 'collectd')
     hosts.each do |host|
+      on host, puppet('resource', 'package', 'python', 'ensure=installed')
       on host, puppet('module', 'install', 'puppetlabs-apt'), acceptable_exit_codes: [0]
       on host, puppet('module', 'install', 'puppetlabs-stdlib'), acceptable_exit_codes: [0]
       on host, puppet('module', 'install', 'puppetlabs-concat'), acceptable_exit_codes: [0]