open_graph.py

# -*- coding: utf-8 -*- #
"""Open Graph.

This plugin adds Open Graph Protocol tags to articles.

Use like this in your base.html template:

.. code-block:: jinja2

  {% if article %}
  {% for tag in article.ogtags %}
  <meta property="{{tag[0]}}" content="{{tag[1]|striptags|e}}" />
  {% endfor %}
  {% endif %}

  {% if page  %}
  {% for tag in page.ogtags %}
  <meta property="{{tag[0]}}" content="{{tag[1]|striptags|e}}" />
  {% endfor %}
  {% endif %}

"""
from __future__ import unicode_literals

import os.path

from bs4 import BeautifulSoup
from pelican import generators
from pelican import signals
from pelican.utils import strftime


def open_graph_tag_articles(content_generators):
    """Get different Pelican objects."""
    for generator in content_generators:
        if isinstance(generator, generators.ArticlesGenerator):
            for article in (
                    generator.articles +
                    generator.translations +
                    generator.drafts):
                open_graph_tag(article)
        elif isinstance(generator, generators.PagesGenerator):
            for page in generator.pages:
                open_graph_tag(page)

    return True


def open_graph_tag(item):  # pylint: disable=too-many-branches
    """Open Graph items."""
    ogtags = [('og:title', item.title),
              ('og:type', 'article')]

    image = item.metadata.get('og_image', '')
    if image:
        ogtags.append(('og:image', image))
    else:
        soup = BeautifulSoup(
            item.content,
            'html.parser')
        img_links = soup.find_all('img')
        if img_links:
            img_src = img_links[0].get('src')
            if "http" not in img_src:
                if item.settings.get('SITEURL', ''):
                    img_src = item.settings.get('SITEURL', '') + "/" + img_src
            ogtags.append(('og:image', img_src))

    url = os.path.join(
        item.settings.get(
            'SITEURL',
            ''),
        item.url)
    ogtags.append(('og:url', url))

    default_summary = item.summary
    description = item.metadata.get('og_description', default_summary)
    ogtags.append(('og:description', description))

    default_locale = item.settings.get('LOCALE', [])
    if len(default_locale[0]) > 3:
        default_locale = default_locale[0]
        ogtags.append(
            ('og:locale', item.metadata.get('og_locale', default_locale)))

    ogtags.append(('og:site_name', item.settings.get('SITENAME', '')))

    if hasattr(item, 'date'):
        ogtags.append(('article:published_time',
                       strftime(item.date, "%Y-%m-%d")))

    if hasattr(item, 'modified'):
        ogtags.append(('article:modified_time', strftime(
            item.modified, "%Y-%m-%d")))

    if hasattr(item, 'related_posts'):
        for related_post in item.related_posts:
            url = os.path.join(
                item.settings.get(
                    'SITEURL',
                    ''),
                related_post.url)
            ogtags.append(('og:see_also', url))

    author_fb_profiles = item.settings.get('AUTHOR_FB_ID', {})
    if author_fb_profiles:
        for author in item.authors:
            if author.name in author_fb_profiles:
                ogtags.append(
                    ('article:author', author_fb_profiles[author.name]))

    ogtags.append(('article:section', item.category.name))

    try:
        for tag in item.tags:
            ogtags.append(('article:tag', tag.name))
    except AttributeError:
        pass

    item.ogtags = ogtags


def register():
    """Register pelican plugin."""
    signals.all_generators_finalized.connect(open_graph_tag_articles)