mediagoblin/process_media/__init__.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2011 Free Software Foundation, Inc
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU Affero General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU Affero General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 import Image
  18 from mediagoblin.db.util import ObjectId
  19 from celery.task import task
  20
  21 from mediagoblin import mg_globals as mgg
  22 from contextlib import contextmanager
  23
  24
  25 THUMB_SIZE = 180, 180
  26 MEDIUM_SIZE = 640, 640
  27
  28
  29 def create_pub_filepath(entry, filename):
  30     return mgg.public_store.get_unique_filepath(
  31             ['media_entries',
  32              unicode(entry['_id']),
  33              filename])
  34
  35 @contextmanager
  36 def closing(callback):
  37     try:
  38         yield callback
  39     finally:
  40         pass
  41
  42 @task
  43 def process_media_initial(media_id):
  44     workbench = mgg.workbench_manager.create_workbench()
  45
  46     entry = mgg.database.MediaEntry.one(
  47         {'_id': ObjectId(media_id)})
  48
  49     queued_filepath = entry['queued_media_file']
  50     queued_filename = workbench.localized_file(
  51         mgg.queue_store, queued_filepath,
  52         'source')
  53
  54     thumb = Image.open(queued_filename)
  55     thumb.thumbnail(THUMB_SIZE, Image.ANTIALIAS)
  56     # ensure color mode is compatible with jpg
  57     if thumb.mode != "RGB":
  58         thumb = thumb.convert("RGB")
  59
  60     thumb_filepath = create_pub_filepath(entry, 'thumbnail.jpg')
  61
  62     thumb_file = mgg.public_store.get_file(thumb_filepath, 'w')
  63     with closing(thumb_file):
  64         thumb.save(thumb_file, "JPEG", quality=90)
  65
  66     """
  67     If the size of the original file exceeds the specified size of a `medium`
  68     file, a `medium.jpg` files is created and later associated with the media
  69     entry.
  70     """
  71     medium = Image.open(queued_filename)
  72     medium_processed = False
  73
  74     if medium.size[0] > MEDIUM_SIZE[0] or medium.size[1] > MEDIUM_SIZE[1]:
  75         medium.thumbnail(MEDIUM_SIZE, Image.ANTIALIAS)
  76
  77         if medium.mode != "RGB":
  78             medium = medium.convert("RGB")
  79
  80         medium_filepath = create_pub_filepath(entry, 'medium.jpg')
  81
  82         medium_file = mgg.public_store.get_file(medium_filepath, 'w')
  83         with closing(medium_file):
  84             medium.save(medium_file, "JPEG", quality=90)
  85             medium_processed = True
  86
  87     # we have to re-read because unlike PIL, not everything reads
  88     # things in string representation :)
  89     queued_file = file(queued_filename, 'rb')
  90
  91     with queued_file:
  92         original_filepath = create_pub_filepath(entry, queued_filepath[-1])
  93
  94         with closing(mgg.public_store.get_file(original_filepath, 'wb')) as original_file:
  95             original_file.write(queued_file.read())
  96
  97     mgg.queue_store.delete_file(queued_filepath)
  98     entry['queued_media_file'] = []
  99     media_files_dict = entry.setdefault('media_files', {})
 100     media_files_dict['thumb'] = thumb_filepath
 101     media_files_dict['original'] = original_filepath
 102     if medium_processed:
 103         media_files_dict['medium'] = medium_filepath
 104     entry['state'] = u'processed'
 105     entry.save()
 106
 107     # clean up workbench
 108     workbench.destroy_self()