boards/templatetags/board.py

import re
from django.shortcuts import get_object_or_404
from django import template


IMG_ACTION_URL = '[<a href="{}">{}</a>]'


register = template.Library()

actions = [
    {
        'name': 'google',
        'link': 'http://google.com/searchbyimage?image_url=%s',
    },
    {
        'name': 'iqdb',
        'link': 'http://iqdb.org/?url=%s',
    },
]


@register.simple_tag(name='post_url')
def post_url(*args, **kwargs):
    post_id = args[0]

    post = get_object_or_404('Post', id=post_id)

    return post.get_absolute_url()


@register.simple_tag(name='image_actions')
def image_actions(*args, **kwargs):
    image_link = args[0]
    if len(args) > 1:
        image_link = 'http://' + args[1] + image_link  # TODO https?

    return ', '.join([IMG_ACTION_URL.format(
        action['link'] % image_link, action['name']) for action in actions])


@register.simple_tag(name='post_view')
def post_view(post, *args, **kwargs):
    return post.get_view(*args, **kwargs)