splinext/frontpage/controllers/frontpage.py

   1 from collections import defaultdict
   2 import datetime
   3 import logging
   4 import re
   5
   6 from pylons import config, request, response, session, tmpl_context as c, url
   7 from pylons.controllers.util import abort, redirect_to
   8 from routes import request_config
   9 from sqlalchemy.orm.exc import NoResultFound
  10
  11 from spline.lib import helpers as h
  12 from spline.lib.base import BaseController, render
  13 from spline.lib.plugin.load import run_hooks
  14
  15 log = logging.getLogger(__name__)
  16
  17 class FrontPageController(BaseController):
  18
  19     def index(self):
  20         """Magicaltastic front page.
  21
  22         Plugins can register a hook called 'frontpage_updates_<type>' to add
  23         updates to the front page.  `<type>` is an arbitrary string indicating
  24         the sort of update the plugin knows how to handle; for example,
  25         spline-forum has a `frontpage_updates_forum` hook for posting news from
  26         a specific forum.
  27
  28         Hook handlers should return a list of FrontPageUpdate objects.
  29
  30         Standard hook parameters are:
  31         `limit`, the maximum number of items that should ever be returned.
  32         `max_age`, the number of seconds after which items expire.
  33         `title`, a name for the source.
  34         `icon`, an icon to show next to its name.
  35
  36         `limit` and `max_age` are also global options.
  37
  38         Updates are configured in the .ini like so:
  39
  40             spline-frontpage.sources.foo = updatetype
  41             spline-frontpage.sources.foo.opt1 = val1
  42             spline-frontpage.sources.foo.opt2 = val2
  43
  44         Note that the 'foo' name is completely arbitrary and is only used for
  45         grouping options together.  This will result in a call to:
  46
  47             run_hooks('frontpage_updates_updatetype', opt1=val1, opt2=val2)
  48
  49         Local plugins can override the fairly simple index.mako template to
  50         customize the front page layout.
  51         """
  52         # XXX no reason to do this on the fly; cache it on server startup
  53         update_config = defaultdict(dict)  # source_name => config
  54         key_rx = re.compile(
  55             '(?x) ^ spline-frontpage [.] sources [.] (\w+) (?: [.] (\w+) )? $')
  56         for key, val in config.iteritems():
  57             match = key_rx.match(key)
  58             if not match:
  59                 continue
  60
  61             source_name, subkey = match.groups()
  62             if not subkey:
  63                 # This is the type declaration; use a special key
  64                 subkey = '__type__'
  65
  66             if subkey in ('limit', 'max_age'):
  67                 val = int(val)
  68             update_config[source_name][subkey] = val
  69
  70         global_limit = int(config.get('spline-frontpage.limit', 10))
  71         now = datetime.datetime.now()
  72         try:
  73             global_max_age = now - datetime.timedelta(
  74                 seconds=int(config['spline-frontpage.max_age']))
  75         except KeyError:
  76             global_max_age = None
  77
  78         # Ask plugins to deal with this stuff for us!
  79         updates = []
  80         for source, source_config in update_config.iteritems():
  81             hook_name = 'frontpage_updates_' + source_config['__type__']
  82
  83             # Merge with the global config
  84             merged_config = source_config.copy()
  85             del merged_config['__type__']
  86
  87             merged_config['limit'] = min(
  88                 merged_config.get('limit', global_limit),
  89                 global_limit,
  90             )
  91
  92             try:
  93                 local_max_age = now - datetime.timedelta(
  94                     seconds=merged_config['max_age'])
  95             except KeyError:
  96                 local_max_age = None
  97
  98             if global_max_age and local_max_age:
  99                 merged_config['max_age'] = max(global_max_age, local_max_age)
 100             else:
 101                 merged_config['max_age'] = global_max_age or local_max_age
 102
 103             # Hooks should return a list of FrontPageUpdate-like objects,
 104             # making this return value a list of lists
 105             updates_lol = run_hooks(hook_name, **merged_config)
 106             updates += sum(updates_lol, [])
 107
 108             # Little optimization: maximum age effectively becomes the age of
 109             # the oldest thing that would still appear on the page, as anything
 110             # older would drop off the end no matter what.
 111             # So sort by descending time and crop each iteration...
 112             updates.sort(key=lambda obj: obj.time, reverse=True)
 113             updates = updates[:global_limit]
 114
 115             if updates:
 116                 global_max_age = updates[-1].time
 117
 118         c.updates = updates
 119
 120         return render('/index.mako')