lab-03.2-Create-a-module

Lab 3.2: Create a module

We’re going to start off with a relatively simple review module that should manage a named user and some configuration files. We'll also manage a file in a separate class.

First, we will add a single $user parameter to define the username to manage. If the user is root, the path to the user’s home directory will have to change to reflect that. Then we’ll add a class that will manage the /etc/motd.

Since the catalog is compiled on the master, we'll need to use some logic to extrapolate the user’s home directory.

$homedir = $user ? {
  'root'  => '/root',
  default => "/home/${user}",
}

For the rest of this course, we will refer to the /etc/puppetlabs/code/environments/production/modules as [modulepath]. You can find this again with running cd $(puppet agent --configprint environmentpath)/production/modules and will be used for all labs.

We haven't explained to you how to do most of these tasks, so please request assistance from the instructor as needed.

Steps

Create the review module using PDK

1. Change directory to your [modulepath] by running

   cd $(puppet agent --configprint environmentpath)/production/modules

2. Run this command:

   pdk new module

3. You will see several questions requiring an answer. Enter these answers:

   Replace the N in studentN with your student number (for example, student8).

   Question	Answer
   Module Name	review
   Forge Name	studentN
   Credit author	Student N
   License	Apache-2.0
   Operating reviews	RedHat

Update the class

1. Navigate to your review directory.

   cd review

2. Create the class.

   pdk new class review

3. Edit manifests/init.pp

   • Add a single parameter, $user, defaulting to review

4. The class should manage:

   • The $user user with a .bashrc in their home directory.
   • Ensure that the puppet service is stopped.
   • Declare a class named review::motd.

Create a new class

1. Create a class named review::motd in the proper location.

   pdk new class motd

2. Leave the body of the class blank. We'll finish it soon.

Test your work

Expect an error from the following command.

1. Create your smoke test file to validate your work.

   cd examples

2. Edit examples/init.pp

3. Validate your syntax using pdk.

   pdk validate

4. Using puppet apply, validate your smoke test.

   puppet apply examples/init.pp --noop

Solution

Your module structure should resemble

[root@training modules]# tree review/

  review/
  ├── examples
  │   ├── motd.pp
  │   └── init.pp
  ├── files
  │   └── bashrc
  └── manifests
      ├── motd.pp
      └── init.pp

Example file: review/manifests/motd.pp

class review::motd {
}

Example file: review/manifests/init.pp

# A description of what this class does
#
# @summary A short summary of the purpose of this class
#
# @example
#   include review
class review (
  $user = 'review',
) {
  include review::motd

  $homedir = $user ? {
    'root'  => '/root',
    default => "/home/${user}",
  }

  user { $user:
    ensure     => present,
    shell      => '/bin/bash',
    managehome => true,
  }

  file { "${homedir}/.bashrc":
    ensure => file,
    owner  => $user,
    group  => $user,
    mode   => '0644',
    source => 'puppet:///modules/review/bashrc'
  }

  service { 'puppet':
    ensure => stopped,
    enable => false,
  }
}

Example file: review/files/bashrc

# .bashrc
# User specific aliases and functions

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi

| Previous Lab | Next Lab |