Extending Jinja2 Templates

Jinja2 templates can use the {% extends %} directive to inherit file fragments which might be common to many configuration files.

Use the “jinja2_include” suffix for file fragments you will extend.

/var/lib/bcfg2/Cfg/foo/common.jinja2_include

[global]
setting1 = true
setting2 = false
{% block setting3 %}setting3 = "default value"{% endblock %}

{% block section1 -%}
[section1]
setting4 = true
setting5 = false
{%- endblock %}

{% block section2 -%}
[section2]
setting6 = true
setting7 = false
{%- endblock %}

/var/lib/bcfg2/Cfg/foo/foo.H_hostname.jinja2

{% extends "common.jinja2_include" %}
{% block setting3 %}setting3 = "new value"{% endblock %}
{% block section1 -%}
[section1]
setting4 = false
setting5 = false
{%- endblock %}

Output

[global]
setting1 = true
setting2 = false
setting3 = "new value"

[section1]
setting4 = false
setting5 = false

[section2]
setting6 = true
setting7 = false