Question

I have two models news.article and portfolio.entry. Both models have a BooleanField for setting “is_campaign” to true.

Im trying to write a custom templatetag so I can get the latest campaign article (There should only be one)

Here is my templatetag: campaign_article.py

from itertools import chain
from django import template

from news.models import Article
from portfolio.models import Entry

register = template.Library()

def get_campaign():
        #Get the newest news article with is_campaign=True
        article = Article.objects.filter(is_campaign=True).order_by('-pub_date')[:1]

        #Get the newest portfolio entry with is_campaign=True
        portfolio = Portfolio_entry.objects.filter(is_campaign=True).order_by('-pub_date')[:1]

        #combine article, and entry and display only the newest
        campaign_article = list(chain(article, portfolio))[:1]


        return {'campaign_article': campaign_article}



register.tag('campaign', get_campaign)

I have tried this in my template:

{% load campaign_article %}
{% for campaign_article in campaign %}

{{ campaign_article.id }}

{% endfor %}

But I don’t get any output. Is this the wrong method ?

Answer 1

You would want to create assignment_tag rather than a generic tag.
So you can update your tag as:

def get_campaign():
    #your stuff
    ....

    return campaign_article

register.assignment_tag(get_campaign, name='campaign')

And update template as:

{% load campaign_article %}
{% campaign as campaign_list %} {# loads the tags and creates campaign_list context variable #}
{% for campaign_article in campaign_list %}
    {{ campaign_article.id }}
{% endfor %}