Noop

A Puppet DSL noop() function for setting a whole scope to noop.

Compatibility Notice

Versions of the module above 1.0.0 utilize the "modern" Puppet Function Ruby API and thus will not work on older versions of Puppet. Time to really explore upgrading from Puppet 3 I guess :)

Usage

This is a statement function that accepts one optional Boolean or Undef argument. It can be called at any scope. Its effects will propagate into child scopes.

class ssh {

  noop()
  include ssh::client

  package { 'openssh-server' :
    ensure => installed,
  }

  file { '/etc/ssh/sshd_config':
    ensure => file,
  }

  service { 'sshd':
    ensure  => running,
    require => Package['openssh-server'],
  }
}

class ssh::client {
  noop(undef)

  file { '/etc/ssh/ssh_config':
    ensure => file,
  }
}

In the above example, none of the resources in Class['ssh'] will be enforced. The resources in Class['ssh::client'] WILL be enforced, because the default noop value is reset in the child's scope. Without noop(undef) in Class['ssh::client'], the parent scope's default noop value (as set with the noop() function) would be inherited.

Another option would be to call noop(false) instead of noop(undef) in Class['ssh::client']. The difference between these two options is how the resources will behave if Puppet runs with the --noop setting or CLI argument. When noop(undef) is used to reset the noop default in Class['ssh::client'], the CLI --noop flag will still work to set these resources to noop. If noop(false) is used, however, these resources will never noop—not even when --noop is used on the command line.

Class interface

A convenience function is provided to implement a pattern for controlling noop at the class level. Here's how it works:

# This class demonstrates a standard interface for controlling noop behavior.
# The standard interface consists of two class parameters:
#
#   $class_noop:
#   Required interface parameter. Ensure resources in this class are not
#   enforced even when the Puppet agent is run in enforcement mode. This
#   parameter can be used to "turn off" a class. This parameter may be
#   combined with the noop::true_unless_no_noop() function as its default
#   value so that classes may default to enforcement=off, but can be easily
#   enforced on-demand during a one-time Puppet run using
#   `puppet agent -t --no-noop`.
#
#   $class_noop_override:
#   Optional interface parameter. Ensure resources in this class use the
#   provided noop value regardless of either the $class_noop value OR the
#   agent-level noop value. This parameter can be used to "turn on" a class,
#   even for agents running in noop mode.
#
class example::annotated (
  Boolean           $class_noop          = noop::true_unless_no_noop(), #required
  Optional[Boolean] $class_noop_override = undef, #optional
) {
  noop::class_interface()
  # WARNING: this class should now be considered a "leaf" class. Do not call
  # `include` or similar functions from this point forward without careful
  # consideration of how these scope defaults will propagate. Doing so may
  # cause unexpected side effects!
  #
  #     https://puppet.com/docs/puppet/5.3/lang_scope.html
  #     https://puppet.com/docs/puppet/5.3/lang_defaults.html

  # The noop metaparameter default is set automatically based on scope
  # defaults invoked by the noop::class_interface() function call above, which
  # in turn is determined by the $class_noop parameter, and/or the
  # $class_noop_override parameter. The explicit equivalent has been mocked in
  # as a comment, for illustration.
  file { '/tmp/annotated.txt':
    ensure  => file,
    content => "Content from example::annotated\n",
    # noop    => $value_determined_by_interface_parameters,
  }

}

class profile::unannotated (
  Boolean           $class_noop = noop::true_unless_no_noop(),
  Optional[Boolean] $class_noop_override = undef,
) {
  noop::class_interface()

  file { '/tmp/unannotated.txt':
    ensure  => file,
    content => "Content from example::unannotated\n",
  }

}

License

Copyright 2012 Thomas Linkin [email protected]

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.