splinext/frontpage/__init__.py

   1 from collections import defaultdict, namedtuple
   2 from pkg_resources import resource_filename
   3 import re
   4 import subprocess
   5
   6 from pylons import config
   7
   8 from spline.lib import helpers
   9 from spline.lib.plugin import PluginBase, PluginLink, Priority
  10 from spline.lib.plugin.load import run_hooks
  11
  12 import splinext.frontpage.controllers.frontpage
  13 from splinext.frontpage.sources import FeedSource, GitSource
  14
  15 def add_routes_hook(map, *args, **kwargs):
  16     """Hook to inject some of our behavior into the routes configuration."""
  17     map.connect('/', controller='frontpage', action='index')
  18
  19 def load_sources_hook(config, *args, **kwargs):
  20     """Hook to load all the known sources and stuff them in config.  Run once,
  21     on server startup.
  22
  23     Frontpage hooks are also passed the `config` hash, as it's not available
  24     during setup.
  25     """
  26     # Extract source definitions from config and store as source_name => config
  27     update_config = defaultdict(dict)
  28     key_rx = re.compile(
  29         '(?x) ^ spline-frontpage [.] sources [.] (\w+) (?: [.] (\w+) )? $')
  30     for key, val in config.iteritems():
  31         # Match against spline-frontpage.source.(source).(key)
  32         match = key_rx.match(key)
  33         if not match:
  34             continue
  35
  36         source_name, subkey = match.groups()
  37         if not subkey:
  38             # This is the type declaration; use a special key
  39             subkey = '__type__'
  40
  41         update_config[source_name][subkey] = val
  42
  43     # Figure out the global limit and expiration time, with reasonable
  44     # defaults.  Make sure they're integers.
  45     global_limit = int(config.get('spline-frontpage.limit', 10))
  46     # max_age is optional and can be None
  47     try:
  48         global_max_age = int(config['spline-frontpage.max_age'])
  49     except KeyError:
  50         global_max_age = None
  51
  52     config['spline-frontpage.limit'] = global_limit
  53     config['spline-frontpage.max_age'] = global_max_age
  54
  55     # Ask plugins to turn configuration into source objects
  56     sources = []
  57     for source, source_config in update_config.iteritems():
  58         hook_name = 'frontpage_updates_' + source_config['__type__']
  59         del source_config['__type__']  # don't feed this to constructor!
  60
  61         # Default to global limit and max age.  Source takes care of making
  62         # integers and whatnot
  63         source_config.setdefault('limit', global_limit)
  64         source_config.setdefault('max_age', global_max_age)
  65
  66         # Hooks return a list of sources; combine with running list
  67         sources += run_hooks(hook_name, config=config, **source_config)
  68
  69     # Save the list of sources, and done
  70     config['spline-frontpage.sources'] = sources
  71
  72 def source_cron_hook(*args, **kwargs):
  73     """Hook to pass on cron tics to all sources, should they need it for e.g.
  74     caching.
  75     """
  76     for source in config['spline-frontpage.sources']:
  77         source.do_cron(*args, **kwargs)
  78
  79 class FrontPagePlugin(PluginBase):
  80     def controllers(self):
  81         return dict(
  82             frontpage = splinext.frontpage.controllers.frontpage.FrontPageController,
  83         )
  84
  85     def template_dirs(self):
  86         return [
  87             (resource_filename(__name__, 'templates'), Priority.FIRST)
  88         ]
  89
  90     def hooks(self):
  91         return [
  92             ('routes_mapping',          Priority.NORMAL,    add_routes_hook),
  93             ('after_setup',             Priority.NORMAL,    load_sources_hook),
  94             ('cron',                    Priority.NORMAL,    source_cron_hook),
  95             ('frontpage_updates_rss',   Priority.NORMAL,    FeedSource),
  96             ('frontpage_updates_git',   Priority.NORMAL,    GitSource),
  97         ]