# along with this program. If not, see <http://www.gnu.org/licenses/>.
import Image
-from mediagoblin.db.util import ObjectId
-from celery.task import task
+from contextlib import contextmanager
+from celery.task import Task
+from celery import registry
+
+from mediagoblin.db.util import ObjectId
from mediagoblin import mg_globals as mgg
+from mediagoblin.process_media.errors import BaseProcessingFail, BadMediaFail
THUMB_SIZE = 180, 180
filename])
-@task
-def process_media_initial(media_id):
- workbench = mgg.workbench_manager.create_workbench()
+@contextmanager
+def closing(callback):
+ try:
+ yield callback
+ finally:
+ pass
+
+
+################################
+# Media processing initial steps
+################################
+
+class ProcessMedia(Task):
+ """
+ Pass this entry off for processing.
+ """
+ def run(self, media_id):
+ """
+ Pass the media entry off to the appropriate processing function
+ (for now just process_image...)
+ """
+ entry = mgg.database.MediaEntry.one(
+ {'_id': ObjectId(media_id)})
+
+ # Try to process, and handle expected errors.
+ try:
+ process_image(entry)
+ except BaseProcessingFail, exc:
+ mark_entry_failed(entry[u'_id'], exc)
+ return
+
+ entry['state'] = u'processed'
+ entry.save()
+
+ def on_failure(self, exc, task_id, args, kwargs, einfo):
+ """
+ If the processing failed we should mark that in the database.
+
+ Assuming that the exception raised is a subclass of BaseProcessingFail,
+ we can use that to get more information about the failure and store that
+ for conveying information to users about the failure, etc.
+ """
+ entry_id = args[0]
+ mark_entry_failed(entry_id, exc)
+
+
+process_media = registry.tasks[ProcessMedia.name]
+
+
+def mark_entry_failed(entry_id, exc):
+ """
+ Mark a media entry as having failed in its conversion.
- entry = mgg.database.MediaEntry.one(
- {'_id': ObjectId(media_id)})
+ Uses the exception that was raised to mark more information. If the
+ exception is a derivative of BaseProcessingFail then we can store extra
+ information that can be useful for users telling them why their media failed
+ to process.
+
+ Args:
+ - entry_id: The id of the media entry
+
+ """
+ # Was this a BaseProcessingFail? In other words, was this a
+ # type of error that we know how to handle?
+ if isinstance(exc, BaseProcessingFail):
+ # Looks like yes, so record information about that failure and any
+ # metadata the user might have supplied.
+ mgg.database['media_entries'].update(
+ {'_id': entry_id},
+ {'$set': {u'state': u'failed',
+ u'fail_error': exc.exception_path,
+ u'fail_metadata': exc.metadata}})
+ else:
+ # Looks like no, so just mark it as failed and don't record a
+ # failure_error (we'll assume it wasn't handled) and don't record
+ # metadata (in fact overwrite it if somehow it had previous info
+ # here)
+ mgg.database['media_entries'].update(
+ {'_id': entry_id},
+ {'$set': {u'state': u'failed',
+ u'fail_error': None,
+ u'fail_metadata': {}}})
+
+
+def process_image(entry):
+ """
+ Code to process an image
+ """
+ workbench = mgg.workbench_manager.create_workbench()
queued_filepath = entry['queued_media_file']
queued_filename = workbench.localized_file(
mgg.queue_store, queued_filepath,
'source')
- thumb = Image.open(queued_filename)
+ try:
+ thumb = Image.open(queued_filename)
+ except IOError:
+ raise BadMediaFail()
+
thumb.thumbnail(THUMB_SIZE, Image.ANTIALIAS)
# ensure color mode is compatible with jpg
if thumb.mode != "RGB":
thumb_filepath = create_pub_filepath(entry, 'thumbnail.jpg')
thumb_file = mgg.public_store.get_file(thumb_filepath, 'w')
- with thumb_file:
+ with closing(thumb_file):
thumb.save(thumb_file, "JPEG", quality=90)
- """
- If the size of the original file exceeds the specified size of a `medium`
- file, a `medium.jpg` files is created and later associated with the media
- entry.
- """
+ # If the size of the original file exceeds the specified size of a `medium`
+ # file, a `medium.jpg` files is created and later associated with the media
+ # entry.
medium = Image.open(queued_filename)
medium_processed = False
medium_filepath = create_pub_filepath(entry, 'medium.jpg')
medium_file = mgg.public_store.get_file(medium_filepath, 'w')
- with medium_file:
+ with closing(medium_file):
medium.save(medium_file, "JPEG", quality=90)
medium_processed = True
with queued_file:
original_filepath = create_pub_filepath(entry, queued_filepath[-1])
- with mgg.public_store.get_file(original_filepath, 'wb') as original_file:
+ with closing(mgg.public_store.get_file(original_filepath, 'wb')) as original_file:
original_file.write(queued_file.read())
mgg.queue_store.delete_file(queued_filepath)
media_files_dict['original'] = original_filepath
if medium_processed:
media_files_dict['medium'] = medium_filepath
- entry['state'] = u'processed'
- entry.save()
# clean up workbench
workbench.destroy_self()
projects / mediagoblin.git / blobdiff