Testing Ansible roles with Molecule.

1. Testing Ansible roles with Molecule
Werner Dijkerman, Nieuwegein, 17-05-2017

2. Confidential and Business Information
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2

3. 3
Contents
1. Introduction
1. me
2. iWelcome
3. Why testing
2. Molecule v1
3. Molecule v2
4. Walkthrough

4. 4
Introduction
- name: Werner Dijkerman
work:
title: System Engineer (Engineering)
employer: iWelcome
contact:
- @djwasabiman
- www.werner-dijkerman.nl
other:
technical_reviewer:
- Zabbix Network Monitoring 2nd (Packt Pub, book)
- Learning Docker 2nd (Packt Pub, book)
- Advanced IT Automation with Ansible 2 (Packt Pub, Video)
cats: True

5. 5
Identity & Access Management (‘IAM’):
The ICT infrastructure required to provide &
manage the right access for the right people, at
the right place, on the right device to the right IT-
services, and to do that in a safe, simple, cost-
efficient and controllable manner.
IDaaS: 100% delivered as a cloud service

6. 6
Selection of blue chip customers using iWelcome IDaaS for Workforce and / or CIAM use cases

7. 7
Introduction
o Why do we test Ansible roles?
Does the role do what it needs to do:
• Is it installing the application(s)?
• Is it configuring the correct templates?
• Is the service(s) running?
• etc

8. 8
Introduction
What do we get for testing roles:
Improving reliability:
• We get more confidence and see that it works
• Run the tests when Pull Requests are created
Better quality:
• Add functionality and/or tests

9. 9
Molecule v1
“Molecule is designed to aid in the development and testing of
Ansible roles including support for multiple instances, operating
system distributions, virtualization providers and test frameworks.”
pip install molecule
https://github.com/metacloud/molecule
https://molecule.readthedocs.io/

10. 10
Molecule v1
Drivers:
• Vagrant (Default)
• OpenStack
• Docker
New Ansible role:
molecule init --driver docker --role <role_name>
When you already have a role:
molecule init --driver docker
https://molecule.readthedocs.io/en/stable-1.24/driver/index.html

11. 11
Molecule v1
o Providers (Specific to driver: Vagrant)
• Virtualbox (Default)
• Libvrt
• Parallels
• VMware Fusion
https://molecule.readthedocs.io/en/stable-1.24/provider/
index.html

12. 12
Molecule v1
o Verifiers
Used for the validation/testing of the role.
• TestInfra (Default)
• ServerSpec
• Goss
https://molecule.readthedocs.io/en/stable-1.24/verifier.html

13. 13
Molecule v1
o Molecule subcommands
• molecule login ( --host <instance_name> )
• molecule syntax
• molecule create
• molecule converge
• molecule idempotence
• molecule verify
• ansible-lint
• flake
• Testinfra / Serverspec / Goss
• molecule destroy
All can be done with the subcommand: molecule test

14. 14
Molecule v1
Ansible role dependencies
Ansible configuration
Molecule configuration
Docker driver
Verifier configuration
molecule.yml

15. 15
Molecule v2
Molecule v2
• Ansible lint has own sub command
• Docker (Default driver)
• Using Scenarios!
http://molecule.readthedocs.io/en/v2/

16. 16
Molecule v2
http://molecule.readthedocs.io/en/v2/configuration.html#scenario

17. 17
Walkthrough
Using SystemD
https://github.com/dj-wasabi/ansible-zabbix-agent/blob/master/
molecule.yml#L26

18. 18
Walkthrough
Using group_vars
https://github.com/dj-wasabi/ansible-zabbix-server/blob/
master/molecule.yml#L16

19. 19
Walkthrough
Multiple instances like running a cluster
molecule.yml playbook.yml

20. 20
Walkthrough
Execution of role depends on other service
https://github.com/dj-wasabi/ansible-ossec-agent/blob/
master/playbook.yml

21. 21
Walkthrough
TestInfra check per distribution
https://github.com/dj-wasabi/ansible-zabbix-server/blob/
master/tests/test_default.py#L63

22. Thank you for your attention!