Local Facts role

dmccuk.local_facts is an Ansible role that gives you a framework to implement local facts within your server environment with minimal setup. You can create facts relevant to your organisation by updating the files/customFactSetup.sh script with your own defaults.

I have included both AWS and AZURE fact generation to give you an example of how to set this up. Make your own adjustments as required.

This role installs NO packages.
Creates a local /etc/ansible/facts.d/local.fact file in the default ansible location.
Runs a script to collect facts and add them to the local.fact file.
Example: Creates a local /tmp/local_facts file containg some of the custom facts.
Example AWS fact creation can be found in files/customFactSetup.sh

Edit as required.

Installation

Using ansible-galaxy:

$ ansible-galaxy install dmccuk.local_facts

Using ansible-galaxy to install to the current directory:

$ ansible-galaxy install --roles-path . dmccuk.local_facts

Using requirements.yml:

- src: dmccuk.local_facts

Using git:

$ git clone https://github.com/dmccuk/local-facts.git

Requirements

There are no specific requirements to use this role. Just an ansible version of 2.5 or above.

In the code I give examples of creating local facts from AWS meta-data. You can use this or remove it and add your own.

Role Variables

There are no specific role variables. Instead you can configure you're own variables to pull out custom facts and use them in your playbooks.

Dependencies

Ansible >= 2.5

Example Playbook

An example of how to use the role:

- hosts: all
  gather_facts: True
  roles:
    - local_facts

License

BSD

Creating Custom facts

Custom facts are created by running a script that works out the facts and populates the /etc/ansible/fact.d/local.fact file. In this role, you can find the script under ..file/customFactSetup.sh. I have given you some simple examples of creating facts based on AWS meta-data as well as an example case statements to provide logic for how the fact will be populated.

The default/main.yml file converts the ansible_local_facts into varibles we can use in our playbooks. For example:

---
# defaults file for local_facts
server_env: "{{ ansible_local.local.local_facts.support_team }}"
support_team: "{{ ansible_local.local.local_facts.support_team }}"
ec2_region: "{{ ansible_local.local.local_facts.ec2_region }}"

You can update these examples to fit your needs.

Example clone and run

In this example, I clone the role and run it against the localhost. To run against your inventory, just change the - hosts: <server> to what you need it to be.

$ ansible-galaxy install --roles-path . dmccuk.local_facts
- downloading role 'local_facts', owned by dmccuk
- downloading role from https://github.com/dmccuk/local-facts/archive/master.tar.gz
- extracting dmccuk.local_facts to /home/ubuntu/dmccuk.local_facts
- dmccuk.local_facts (master) was installed successfully

$ vi deploy.yaml
- hosts: localhost
  connection: local
  gather_facts: True
  roles:
    - dmccuk.local_facts

$ ansible-playbook deploy.yaml
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match
'all'

PLAY [localhost] *****************************************************************************************************

TASK [Gathering Facts] ***********************************************************************************************
ok: [localhost]

TASK [dmccuk.local_facts : Create custom fact directory] *************************************************************
changed: [localhost]

TASK [dmccuk.local_facts : Insert empty local fact file] *************************************************************
changed: [localhost]

TASK [dmccuk.local_facts : Insert custom fact script] ****************************************************************
changed: [localhost]

TASK [dmccuk.local_facts : add Instance facts] ***********************************************************************
changed: [localhost]

TASK [dmccuk.local_facts : local facts] ******************************************************************************
ok: [localhost] => {
    "ansible_local": "VARIABLE IS NOT DEFINED!"
}

TASK [dmccuk.local_facts : reload facts] *****************************************************************************
ok: [localhost]

TASK [dmccuk.local_facts : create a local facts file] ****************************************************************
changed: [localhost]

PLAY RECAP ***********************************************************************************************************
localhost                  : ok=8    changed=5    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

$ cat /etc/ansible/facts.d/local.fact
[local_facts]
EC2_INSTANCE_TYPE: t2.micro
EC2_AVAIL_ZONE: eu-central-1b
EC2_REGION: eu-central-1
AMI_ID: ami-09356619876445425
environment: Dev
Support_Team: web
Callout: 8-6

$ cat /tmp/local_facts
These are the ansible variables from the playbook:
you can use them in a template like this:

environment is web
The server support team is the web team.
Your EC2 regions is eu-central-1.

View the local facts using JQ

To view the local facts file you just created, make sure JQ is installed and run the following:

$ ansible localhost -m setup | sed '1 s/^.*$/{/' | jq '.ansible_facts.ansible_local.local'
{
  "local_facts": {
    "ami_id": "ami-093762347983f511b",
    "avail_zone": "eu-west-2b",
    "callout": "8-6",
    "cloud": "AWS",
    "environment": "Dev",
    "instance_type": "t2.micro",
    "region": "eu-west-2",
    "support_team": "web"
  }
}

Or to greab a specific fact, you can run the following:

$ ansible localhost -m setup | sed '1 s/^.*$/{/' | jq '.ansible_facts.ansible_local.local.local_facts.instance_type'
"t2.micro"

Now make the changes you need for your environment re-run.

Author Information

Dennis McCarthy

dmccuk/local_facts