Template Tags & Filters¶

Duck allows you to extend templates using template tags and filters, supporting both Jinja2 and Django template engines.

This gives you the flexibility to write reusable logic directly in templates 🌟.

Syntax Overview¶

Default Template Tag¶

Django: {% sometag 'inputs' %} — inputs are the arguments.
Jinja2: {{ sometag('inputs') }} — inputs are the arguments.

Block Template Tag¶

Django: {% sometag %} Some data {% endsometag %}
Jinja2: {% sometag %} Some data {% endsometag %}

Template Filter¶

Django: {{ somevalue | somefilter }}
Jinja2: {{ somevalue | somefilter }}

Quick Cheatsheet¶

Feature	Django Syntax	Jinja2 Syntax
Default Template Tag	`{% tag 'args' %}`	`{{ tag('args') }}`
Block Template Tag	`{% tag %} ... {% endtag %}`	`{% tag %} ... {% endtag %}`
Template Filter	`{{ value	filter }}`

Example Usage¶

# templatetags.py
from duck.template.templatetags import TemplateTag, TemplateFilter, BlockTemplateTag

# Define a regular template tag
def mytag(arg1, context):
    # Custom logic here
    return "some data"

# Define a template filter
def myfilter(data):
    # Process data
    return data

# Define a block template tag
def myblocktag(content):
    # Process block content
    return content

# Register your tags and filters
TEMPLATETAGS = [
    TemplateTag("name_here", mytag, takes_context=True),  # takes_context defaults to False
    TemplateFilter("name_here", myfilter),
    BlockTemplateTag("name_here", myblocktag)
]

Notes¶

For Django templates rendered via django.shortcuts.render, insert this at the top of your template:

{% load ducktags %}

This is only required if the Django project is integrated into Duck.
If using Duck’s internal render functions or classes like TemplateResponse, no extra loading is needed.
Use this primarily for standalone Django templates unrelated to Duck’s template system.

✨ With Duck template tags & filters, you can write cleaner templates, reuse logic, and mix powerful Python code into templates effortlessly 🏷️