TagCloud

tag_cloud.html

<ul class="tag-cloud">
{% for tag in tags %}
    <li class="{{ tag.style_class }}">
        <a href="{% url 'tag-detail' tag.slug %}">{{ tag }}</a>
    </li>
{% endfor %}
</ul>

tag_cloud.py

from django import template
from django.db.models import Count, Max
from classytags.core import Tag as ClassyTag

from static_blog.models import Tag


register = template.Library()


class TagCloud(ClassyTag):
    name = 'tag_cloud'

    def render_tag(self, context):
        tags_with_count = Tag.objects.annotate(count=Count('articles'), last_used=Max('articles__date_published'))\
            .order_by('-count', '-last_used')

        # tags_with_count = sorted(tags_with_count, key=lambda i: i.count, reverse=True)
        max_count = tags_with_count[0].count
        min_count = tags_with_count[30].count
        tags_with_count = [tag for tag in tags_with_count if tag.count >= min_count][:50]

        styles = []
        for x in range(1, 12):
            style = 'size{}'.format(x)
            styles.append(style)

            if x >= 8:
                style += '-plus'
                styles.append(style)

        styles = {index: value for index, value in enumerate(styles)}
        counts_per_group = max_count / float(len(styles))

        for tag in tags_with_count:
            index = int(round(tag.count / counts_per_group))
            tag.style_class = styles[index - 1]

        t = template.loader.get_template('blog/tag_cloud.html')
        tags_with_count.sort(key=lambda tag: tag.name)
        return t.render(template.Context({'tags': tags_with_count}))
register.tag(TagCloud)