Jinja (template engine)

Jinja is a web template engine for the Python programming language. It was created by Armin Ronacher and is licensed under a BSD License. Jinja is similar to the Django template engine, but provides Python-like expressions while ensuring that the templates are evaluated in a sandbox. It is a text-based template language and thus can be used to generate any markup as well as source code.
The Jinja template engine allows customization of tags, filters, tests, and globals. Also, unlike the Django template engine, Jinja allows the template designer to call functions with arguments on objects.
Jinja is the default template engine for Flask, as well as Home Assistant's Automations. It is also used by Ansible, Trac, and Salt. It is also used to make SQL macros, for example for use with dbt.

WWW Official Site

Features

Some of the features of Jinja are:

sandboxed execution
automatic HTML escaping to prevent cross-site scripting attacks
template inheritance
compiles down to the optimal Python code just-in-time
optional ahead-of-time template compilation
easy to debug
configurable syntax

Jinja, like Smarty, also ships with an easy-to-use filter system similar to the Unix pipeline.

Syntax

The syntax for printing output in Jinja is using the double curly braces, for example .
Statements which set variables in jinja or those which do not have an output can be wrapped within , using the set keyword. For example sets a variable called foo with a value of 42.
Similar to above, comments in jinja can be written using a number sign instead of a percentage, for example, .
The syntax for creating a filter in Jinja is a vertical bar.
The syntax for creating a test in Jinja is the keyword is as well as the conditions for evaluating the validity of a test, such as for example do something).
For loops can be used to iterate over sequences, while retaining their object properties. The following example demonstrates iterating over a list of users with and fields.

Although and are not allowed inside loops, sequences can be filtered.

Example

Here is a small example of a template file example.html.jinja:

,

and templating code:
from jinja2 import Template
with open as f:
tmpl = Template)
print

This produces the HTML string:

Value with <unsafe> <a href="/wiki/Data">data</a>

1,
2,
3,
4,
5,
6

Note the minus sign after the tag