This repository has code snippets which are used in

Puppet User Group Berlin Workshop Session

• Best practices
• Hiera
• Roles & Profiles

Best practices

Import

Import can overload classes

Fix the example code in best_practices/manifests/import.pp and best_practices/manifests/nodes.pp

Import in modules can load files which are not in proper namesapce.

Fix the example code in best_practices/modules/imports/manifests/init.pp and best_practices/modules/imports/manifests/imports.pp

Inheritance

Node inheritance

Fix the node code in best_practices/manifests/inheritance.pp

Think about proper solutions for replacement of variables on node level.

Class inheritance

Understand the code in best_practices/modules/inheritance/manifests

Rewrite code to a parameterized class.

Remote Modules

Never change remote modules.

Create alocal bare git repository

add github as upstream remote

push code into a branch with name 'upstream'

merge upstream into master

dont forget to fetch the tags

How to get tags into a local repo?

Scoped Variables

Never rely upon dynamic variable lookup.

Change code in best_practices/modules/variables/manifests/init.pp to use variable from more_variables class instead of local variable

Change code in best_practices/modules/variables/manifests/type_define.pp to pass proper variables to content template.

Change code in best_practices/modules/variables/templates/file.erb to use scoped variables.

Change code in best_practices/modules/variables/templates/file.epp to use parameter in template.

Data Validation

Take a look on code in best_practices/modules/data_validation/manifests/init.pp Think on how to prevent entry of wrong data.

1. Make use of stdlib functions
2. Make use of Puppet 4 Data Types

Check hierdata in best_practices/hieradata/common.yaml

Hyphens and Periods

Hyphens are no longer hyphens. They are now a mathematical sign (substraction). Dots are no longer markers which finish something. They are now the separator between an object and its method.

Clean the code from best_practices/hypens-are.ugly/manifests

Hiera

Hierarchy planning

• What is common?
• What does common mean at all?
• Where are differences?
• How to identify whether a node is different?

Where to put the data?

• global (/etc/puppetlabs/code/hieradata)
• environment (/etc/puppetlabs/code/environments/%{environment}/hieradata)
• module (/data)

Hiera lookups

What data lookup to use?

• hiera
• data in environments
  • hiera lookup
  • lookup lookup
• data in modules
  • hiera lookup
  • lookup lookup

Play around with best_practices/modules/data_in_modules/ and best_practices/modules/data_in_modules2

Roles and Profiles

Node inheritance

Node inheritance is no longer working in Puppet 4

Create Profiles

Profile = Implementation Module

Describes a way how a technical component module should be used on your platform

Create Roles

Role = Business Use Case for a System/Service

Node classification on Roles

Example:

wordpress installation

• what is thebusiness use case?
• what profiles do you need
• what technical component modules do you need?