vcs.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, *args, **kwargs):
  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, config, 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.config = config
  56         self.listing = listing
  57
  58         try:
  59             self.enabled = config.getWoodchuckEnabled()
  60         except Exception:
  61             logging.exception("Setting enabled")
  62
  63     def available(self, check_config=True):
  64         if not PyWoodchuck.available(self):
  65             return False
  66         if check_config:
  67             return self.config.getWoodchuckEnabled()
  68         return True
  69
  70     def not_available(self, *args, **kwargs):
  71         return False
  72
  73     # Woodchuck upcalls.
  74     def stream_update_cb(self, stream, *args, **kwargs):
  75         logger.debug("stream update called on %s (%s)"
  76                      % (stream.human_readable_name, stream.identifier,))
  77
  78         # Make sure no one else is concurrently updating this
  79         # feed.
  80         try:
  81             self.listing.updateFeed(stream.identifier)
  82         except:
  83             logger.debug("Updating %s: %s"
  84                          % (stream.identifier, traceback.format_exc ()))
  85
  86     def object_transfer_cb(self, stream, object,
  87                            version, filename, quality,
  88                            *args, **kwargs):
  89         logger.debug ("object transfer called on %s (%s) in stream %s (%s)"
  90                       % (object.human_readable_name, object.identifier,
  91                          stream.human_readable_name, stream.identifier))
  92         try:
  93             self[stream.identifier][object.identifier].dont_transfer = True
  94         except Exception, e:
  95             logger.warn("Setting '%s'(%s).'%s'(%s).DontTransfer: %s"
  96                         % (stream.human_readable_name, stream.identifier,
  97                            object.human_readable_name, object.identifier,
  98                            str(e)))
  99
 100 _w = None
 101 def wc_init(config, listing, request_feedback=False):
 102     """Connect to the woodchuck server and initialize any state."""
 103     global _w
 104     assert _w is None
 105
 106     _w = mywoodchuck (config, listing, "FeedingIt", "org.marcoz.feedingit",
 107                       request_feedback)
 108
 109     if not woodchuck_imported or not _w.available ():
 110         logger.info("Unable to contact Woodchuck server.")
 111     else:
 112         logger.debug("Woodchuck appears to be available.")
 113
 114 def wc_disable_set(disable=True):
 115     """Disable Woodchuck."""
 116     if disable:
 117         logger.info("Disabling Woodchuck")
 118     else:
 119         logger.info("Enabling Woodchuck")
 120
 121     global _w
 122     if _w is None:
 123         logging.info("Woodchuck not loaded.  Not doing anything.")
 124         return
 125
 126     if not _w.available(check_config=False):
 127         logging.info("Woodchuck not available.  Not doing anything.")
 128         return
 129
 130     try:
 131         _w.enabled = not disable
 132     except Exception:
 133         logger.exception("Disabling Woodchuck")
 134
 135 def wc():
 136     """Return the Woodchuck singleton."""
 137     global _w
 138     assert _w is not None
 139     return _w