Globally getting context in Wagtail site

Question

I am working on a Wagtail project consisting of a few semi-static pages (homepage, about, etc.) and a blog. In the homepage, I wanted to list the latest blog entries, which I could do adding the following code to the HomePage model:

def blog_posts(self):
    # Get list of live blog pages that are descendants of this page
    posts = BlogPost.objects.live().order_by('-date_published')[:4]

    return posts


def get_context(self, request):
    context = super(HomePage, self).get_context(request)
    context['posts'] = self.blog_posts()
    return context

However, I would also like to add the last 3 entries in the footer, which is a common element of all the pages in the site. I'm not sure of what is the best way to do this — surely I could add similar code to all the models, but maybe there's a way to extend the Page class as a whole or somehow add "global" context? What is the best approach to do this?

Damn

Answer 1

This sounds like a good case for a custom template tag.

A good place for this would be in blog/templatetags/blog_tags.py:

import datetime
from django import template
from blog.models import BlogPost

register = template.Library()

@register.inclusion_tag('blog/includes/blog_posts.html', takes_context=True)
def latest_blog_posts(context):
    """ Get list of live blog pages that are descendants of this page """
    page = context['page']
    posts = BlogPost.objects.descendant_of(page).live().public().order_by('-date_published')[:4]

    return {'posts': posts}

You will need to add a partial template for this, at blog/templates/blog/includes/blog_posts.html. And then in each page template that must include this, include at the top:

{% load blog_tags %}

and in the desired location:

{% latest_blog_posts %}

I note that your code comment indicates you want descendants of the given page, but your code doesn't do that. I have included this in my example. Also, I have used an inclusion tag, so that you do not have to repeat the HTML for the blog listing on each page template that uses this custom template tag.

Shipload

Thanks! This works like a charm. Since there will be only one "blog index", all BlogPost should be descendant of this index, that's why I didn't include it. – Damn

@Shipload does wagtail have any of it's own method or process to solve this? – Scene