git.maemo.org Git - feedingit/blob - psa_harmattan/feedingit/pysrc/wc.py

   1 # Copyright (c) 2011 Neal H. Walfield
   2 #
   3 # This program is free software: you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation, either version 3 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 import logging
  17 logger = logging.getLogger(__name__)
  18 import traceback
  19
  20 # Don't fail if the Woodchuck modules are not available.  Just disable
  21 # Woodchuck's functionality.
  22
  23 # Whether we imported the woodchuck modules successfully.
  24 woodchuck_imported = True
  25 try:
  26     import pywoodchuck
  27     from pywoodchuck import PyWoodchuck
  28     from pywoodchuck import woodchuck
  29 except ImportError, exception:
  30     logger.info(
  31         "Unable to load Woodchuck modules: disabling Woodchuck support: %s"
  32         % traceback.format_exc ())
  33     woodchuck_imported = False
  34     class PyWoodchuck (object):
  35         def available(self):
  36             return False
  37     woodchuck = None
  38
  39 # The default channel refresh interval: 6 hours.
  40 refresh_interval = 6 * 60 * 60
  41
  42 class mywoodchuck (PyWoodchuck):
  43     def __init__(self, listing, human_readable_name, identifier,
  44                  request_feedback):
  45         try:
  46             PyWoodchuck.__init__ (self, human_readable_name, identifier,
  47                                   request_feedback)
  48         except Exception, e:
  49             logger.error(
  50                 "Failed to establish a connection to the Woodchuck server: %s"
  51                 % (str(e),))
  52             self.available = self.not_available
  53             return
  54
  55         self.listing = listing
  56
  57     def not_available(self):
  58         return False
  59
  60     # Woodchuck upcalls.
  61     def stream_update_cb(self, stream, *args, **kwargs):
  62         logger.debug("stream update called on %s (%s)"
  63                      % (stream.human_readable_name, stream.identifier,))
  64
  65         # Make sure no one else is concurrently updating this
  66         # feed.
  67         try:
  68             self.listing.updateFeed(stream.identifier)
  69         except:
  70             logger.debug("Updating %s: %s"
  71                          % (stream.identifier, traceback.format_exc ()))
  72
  73     def object_transfer_cb(self, stream, object,
  74                            version, filename, quality,
  75                            *args, **kwargs):
  76         logger.debug ("object transfer called on %s (%s) in stream %s (%s)"
  77                       % (object.human_readable_name, object.identifier,
  78                          stream.human_readable_name, stream.identifier))
  79         try:
  80             self[stream.identifier][object.identifier].dont_transfer = True
  81         except Exception, e:
  82             logger.warn("Setting '%s'(%s).'%s'(%s).DontTransfer: %s"
  83                         % (stream.human_readable_name, stream.identifier,
  84                            object.human_readable_name, object.identifier,
  85                            str(e)))
  86
  87 _w = None
  88 def wc_init(listing, request_feedback=False):
  89     """Connect to the woodchuck server and initialize any state."""
  90     global _w
  91     assert _w is None
  92
  93     _w = mywoodchuck (listing, "FeedingIt", "org.marcoz.feedingit",
  94                       request_feedback)
  95
  96     if not woodchuck_imported or not _w.available ():
  97         logger.info("Unable to contact Woodchuck server.")
  98     else:
  99         logger.debug("Woodchuck appears to be available.")
 100
 101 def wc():
 102     """Return the Woodchuck singleton."""
 103     global _w
 104     assert _w is not None
 105     return _w