Django importing Models from template

Question

In my django project, I have a base.html from which all my templates {% extends 'base.html' %}. In that base template I want to do this to a list of all my algorithms.

{% for algorithm in algorithms %}
   # list them out as links in nav bar
{% endfor %}

But I'm not passing algorithms to the base since it's just extending other templates.

I don't know how to solve this. My thought was to use {% load %} in the base template which would basically.

from algorithms.models import Algorithm
from django import template


register = template.Library()

def GetAlgorithmObjects():

  a = Algorithm.objects.all()

  return {'algorithms': a}

I'm not sure of how load works which would explain this failure. How would you actually implement this or should I go a different path.

Answer 1

You can make it with inclusion tag https://docs.djangoproject.com/en/dev/howto/custom-template-tags/#inclusion-tags

In your app algorithms create directory templatetags and put a file in it named algorithms_tags.py (of course in this directory there must be a file named __init__.py)

Then the content of the file is similar to what you wrote:

from algorithms.models import Algorithm
from django import template

register = template.Library()

@register.inclusion_tag('algorithms/show_algorithms.html')
def show_algorithms():
    a = Algorithm.objects.all()
    return {'algorithms': a}

Then you need a template located at algorithms/templates/algorithms/show_algorithms.html with the following content:

{% for algorithm in algorithms %}
   # list them out as links in nav bar
{% endfor %}

You can use it in your base.html as follows:

{% load algorithms_tags %}

{% show_algorithms %}

Some explanations:

• In {% load algorithms_tags %} "algorithms_tags" is the name of the .py file created in the templatetags directory (without the extension)
• In {% show_algorithms %} "show_algorithms" is the name of the function decorated with register.inclusion_tag in inclusion_tag.py