ansible.builtin.template: Deploy Jinja2 Templates with Ansible (Guide)

By Luca Berton · Published 2024-01-01 · Category: installation

Learn to create and use templates in Ansible Playbooks, including an example of deploying an HTML placeholder using Jinja2 templates in your Nginx webserver.

ansible.builtin.template: Deploy Jinja2 Templates with Ansible (Guide)

How to apply a file template to the target host with Ansible? This is extremely useful for service configuration files, placeholder web pages, reports, and so much more use cases. I'm going to show you a live Playbook with some simple Ansible code. I'm Luca Berton and welcome to today's episode of Ansible Pilot.

Ansible applies a file template

• ansible.builtin.template • Template a file out to a target host • ansible_managed, template_host, template_uid, template_path, template_fullpath, template_destpath, and template_run_date

Today we're talking about Ansible module template. The full name is ansible.builtin.template, it's part of ansible-core and is included in all Ansible installations. It templates a file out to a target host. Templates are processed by the Jinja2 templating language. Also you could use also some special variables in your templates: ansible_managed, template_host, template_uid, template_path, template_fullpath, template_destpath, and template_run_date. It supports a large variety of Operating Systems. For basic text formatting, use the Ansible ansible.builtin.copy module or for empty file Ansible ansible.builtin.file module. For Windows, use the ansible.windows.win_template module instead.

Parameters

• src path - template ("templates/" dir) • dest path - target location • validate string - validation command before ("%s") • backup boolean - no/yes • mode/owner/group - permission • setype/seuser/selevel - SELinux

Let me highlight the most useful parameters for template module. The only required parameters are "src" and "dest". The "src" parameter specifies the template file name. Templates usually are stored under "templates" directories with ".j2" file extension. The "dest" parameter specifies the path where to render the template on the remote machine. The "validate" parameters allow you to specify the validation command to run before copying it into place. It's very useful with configuration files for services. Please note that the special escape sequence "%s" is going to be expanded by Ansible with the destination path. If the "backup" parameter is enabled Ansible creates a backup file including the timestamp information before copying it to the destination. Let me also highlight that we could also specify the permissions and SELinux properties.

## Playbook

Apply a file template with Ansible Playbook

code

• template.yml

---
- name: template module Playbook
  hosts: all
  become: true
  vars:
    page_title: "Placeholder"
    page_description: |
      This is my placeholder page example.
      Multiline is possible ;-)
  tasks:
    - name: install Nginx
      ansible.builtin.apt:
        name: nginx
        state: latest
- name: apply page template
      ansible.builtin.template:
        src: templates/placeholder.html.j2
        dest: /var/www/html/index.html

• templates/placeholder.html.j2

<html>
<head>
  <title>{{ page_title }}</title>
</head>
<body>
  <h1>{{ page_title }}</h1>
  <p>{{ page_description }}</p>
</body>
</html>

execution

$ ansible-playbook -i virtualmachines/ubuntu/inventory apply\ template/template.yml
PLAY [template module Playbook] ***********************************************************************
TASK [Gathering Facts] ****************************************************************************
ok: [ubuntu.example.com]
TASK [install Nginx] ******************************************************************************
changed: [ubuntu.example.com]
TASK [apply page template] ************************************************************************
changed: [ubuntu.example.com]
PLAY RECAP ****************************************************************************************
ubuntu.example.com         : ok=3    changed=2    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

before execution

$ ssh devops@ubuntu.example.com devops@ubuntu:~ $ sudo su root@ubuntu:/home/devops# lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 20.04.3 LTS Release: 20.04 Codename: focal root@ubuntu:/home/devops# apt list installed nginx -a Listing... Done nginx/focal-updates,focal-updates,focal-security,focal-security 1.18.0-0ubuntu1.2 all nginx/focal,focal 1.17.10-0ubuntu1 all

root@ubuntu:/home/devops# ls -al /var/ total 52 drwxr-xr-x 13 root root 4096 Oct 27 15:38 . drwxr-xr-x 19 root root 4096 Oct 27 16:05 .. drwxr-xr-x 2 root root 4096 Apr 15 2020 backups drwxr-xr-x 12 root root 4096 Oct 27 15:43 cache drwxrwxrwt 2 root root 4096 Oct 27 15:38 crash drwxr-xr-x 41 root root 4096 Oct 27 15:49 lib drwxrwsr-x 2 root staff 4096 Apr 15 2020 local lrwxrwxrwx 1 root root 9 Oct 27 15:35 lock -> /run/lock drwxrwxr-x 10 root syslog 4096 Nov 22 11:56 log drwxrwsr-x 2 root mail 4096 Jul 31 2020 mail drwxr-xr-x 2 root root 4096 Jul 31 2020 opt lrwxrwxrwx 1 root root 4 Oct 27 15:35 run -> /run drwxr-xr-x 2 root root 4096 Jul 10 2020 snap drwxr-xr-x 4 root root 4096 Oct 27 15:35 spool drwxrwxrwt 5 root root 4096 Nov 22 11:56 tmp root@ubuntu:/home/devops# ls -al /var/www ls: cannot access '/var/www': No such file or directory

after execution

$ ssh devops@ubuntu.example.com
devops@ubuntu:~ $ sudo su
root@ubuntu:/home/devops# apt list installed nginx -a
Listing... Done
nginx/focal-updates,focal-updates,focal-security,focal-security,now 1.18.0-0ubuntu1.2 all [installed]
nginx/focal,focal 1.17.10-0ubuntu1 all
root@ubuntu:/home/devops# ls -al /var/www/
total 12
drwxr-xr-x  3 root root 4096 Nov 22 12:06 .
drwxr-xr-x 14 root root 4096 Nov 22 12:06 ..
drwxr-xr-x  2 root root 4096 Nov 22 12:06 html
root@ubuntu:/home/devops# ls -al /var/www/html/
total 16
drwxr-xr-x 2 root root 4096 Nov 22 12:06 .
drwxr-xr-x 3 root root 4096 Nov 22 12:06 ..
-rw-r--r-- 1 root root  173 Nov 22 12:06 index.html
-rw-r--r-- 1 root root  612 Nov 22 12:06 index.nginx-debian.html
root@ubuntu:/home/devops# less /var/www/html/index.html
root@ubuntu:/home/devops# cat /var/www/html/index.html
<html>
<head>
<title>Placeholder</title>
</head>
<body>
<h1>Placeholder</h1>
<p>This is my placeholder page example.
Multiline is possible ;-)
</p>
</body>

code with ❤️ in GitHub