splinext/forum/frontpage_sources.py

   1 from collections import namedtuple
   2
   3 from sqlalchemy.orm import contains_eager, joinedload
   4 from pylons import url
   5
   6 from spline.model import meta
   7
   8 from splinext.forum import model as forum_model
   9 from splinext.frontpage.sources import Source
  10
  11 def frontpage_hook(limit, max_age, forum_id):
  12     """Hook to return recent news for the front page."""
  13
  14 FrontPageThread = namedtuple('FrontPageThread', ['source', 'time', 'post'])
  15 class ForumSource(Source):
  16     """Represents a forum whose threads are put on the front page.
  17
  18     ``link``, ``title``, and ``icon`` are all optional; the link and title
  19     default to the forum's thread list and name, and the icon defaults to a
  20     newspaper.
  21
  22     Extra properties:
  23
  24     ``forum_id``
  25         id of the forum to check for new threads.
  26     """
  27
  28     template = '/forum/front_page.mako'
  29
  30     def __init__(self, forum_id, **kwargs):
  31         forum = meta.Session.query(forum_model.Forum).get(forum_id)
  32
  33         # Link is tricky.  Needs url(), which doesn't exist when this class is
  34         # loaded.  Lazy-load it in poll() below, instead
  35         kwargs.setdefault('link', None)
  36         kwargs.setdefault('title', forum.name)
  37         kwargs.setdefault('icon', 'newspapers')
  38         super(ForumSource, self).__init__(**kwargs)
  39
  40         self.forum_id = forum_id
  41
  42     def _poll(self, limit, max_age):
  43         if not self.link:
  44             self.link = url(
  45                 controller='forum', action='threads', forum_id=self.forum_id)
  46
  47         thread_q = meta.Session.query(forum_model.Thread) \
  48             .filter_by(forum_id=self.forum_id) \
  49             .join((forum_model.Post, forum_model.Thread.first_post)) \
  50             .options(
  51                 contains_eager(forum_model.Thread.first_post, alias=forum_model.Post),
  52                 contains_eager(forum_model.Thread.first_post, forum_model.Post.thread, alias=forum_model.Thread),
  53                 joinedload(forum_model.Thread.first_post, forum_model.Post.author),
  54             )
  55
  56         if max_age:
  57             thread_q = thread_q.filter(forum_model.Post.posted_time >= max_age)
  58
  59         threads = thread_q \
  60             .order_by(forum_model.Post.posted_time.desc()) \
  61             [:limit]
  62
  63         updates = []
  64         for thread in threads:
  65             update = FrontPageThread(
  66                 source = self,
  67                 time = thread.first_post.posted_time,
  68                 post = thread.first_post,
  69             )
  70             updates.append(update)
  71
  72         return updates