Ansible - Templates

Templates are an incredibly powerful feature.

Super Simple Example

Most simple template ever:

deployments/test.conf.j2



This is a test template.
Selected color is {{ color }}
That's it.

Playbook, variable defined here:

deployments/test_playbook.yaml



- name: Test Playbook
  hosts: all
  vars:
    color: blue

  tasks:
    - name: Template test
      template:
        src: deployments/test.conf.j2
        dest: /data/test.conf

Bigger Example - Features

The template:

deployments/test.conf.j2



Selected color is {{ color }}


{% if size > 25 %}
Large enough
 {% else %}
Too small
{% endif %}


Here is the list:
{% for f in food %}
{{ f }}
{% endfor %}

The playbook:

deployments/test_playbook.yaml



- name: Playbook to test templates
  hosts: all
  vars:
    color: blue
    size: 30
    volume: 12
    food:
      - apple
      - pizza
      - rice
      - taco

  tasks:
    - name: Template test
      template:
        src: deployments/test.conf.j2
        dest: /data/test.conf

Real Example

web_deploy.yaml


---
- name: A Test Playbook
  hosts: webservers
  tasks:

    - name: Update repo cache and install nginx package
      ansible.builtin.apt:
        name: nginx
        update_cache: yes

    - name: Make sure a service is started, enabled, and not masked
      ansible.builtin.systemd_service:
        state: started
        name: nginx
        enabled: true
        masked: no

    - template:
        src: templates/index.html.j2
        dest: /var/www/html/index.html
        var1: "TEST STRING"
        mode: a+r

The actual template:

templates/index.html.j2



This is a sample page.
Here is the test value: {{ var1 }}
That is it.

Another Real Example

Playbook, variable defined here:

deployments/test_playbook.yaml



---
- name: Test Playbook
  hosts: all
  become: yes
  vars
    nameserver: 192.168.3.2
    domain: lab.net
    data:
     - host: localhost
       IP: 127.0.0.1
     - host: silly-wombat1
       IP: 104.131.68.105
     - host: sneaky-dingo1
       IP: 167.99.9.15
     - host: chirpy-bird1
       IP: 159.65.234.12
     - host: serious-squid1
       IP: 68.183.109.62
     - host: hyper-snail
       IP: 159.89.48.164
     - host: hairy-hog1
       IP: 45.33.72.164

 tasks:

   - name: Resolve File
     template:
       src: deployments/resolv.conf.j2
       dest: /tmp/etc/resolv.conf

   - name: Hosts File
     template:
       src: deployments/hosts.conf.j2
       dest: /tmp/etc/hosts.conf

First template:

deployments/resolv.conf.j2



nameserver {{ nameserver }}
search {{ domain }}

Second template:

deployments/hosts.conf.j2



{% for x in data %}
{{ x['IP'] }} {{ x['host'] }}
{% endfor %}

More Info

You can also configure permissions and ownership for templated files:

- name: Template a file to /etc/my_settings.conf
  ansible.builtin.template:
    src: /templates/my_settings.j2
    dest: /etc/my_settings.conf
    owner: bin
    group: wheel
    mode: '0644'