e4bdc9091c
Fleshing out the base classes and setting up some docstrings. Not everything is totally clear yet, but I think it's on a good track, and getting clearer. This commit sponsored by Ben Finney, on behalf of Free Software Melbourne. Thank you all!
319 lines
11 KiB
Python
319 lines
11 KiB
Python
# GNU MediaGoblin -- federated, autonomous media hosting
|
|
# Copyright (C) 2011, 2012 MediaGoblin contributors. See AUTHORS.
|
|
#
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU Affero General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU Affero General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU Affero General Public License
|
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
import logging
|
|
import os
|
|
|
|
from mediagoblin.db.util import atomic_update
|
|
from mediagoblin import mg_globals as mgg
|
|
|
|
from mediagoblin.tools.translate import lazy_pass_to_ugettext as _
|
|
|
|
_log = logging.getLogger(__name__)
|
|
|
|
|
|
class ProgressCallback(object):
|
|
def __init__(self, entry):
|
|
self.entry = entry
|
|
|
|
def __call__(self, progress):
|
|
if progress:
|
|
self.entry.transcoding_progress = progress
|
|
self.entry.save()
|
|
|
|
|
|
def create_pub_filepath(entry, filename):
|
|
return mgg.public_store.get_unique_filepath(
|
|
['media_entries',
|
|
unicode(entry.id),
|
|
filename])
|
|
|
|
|
|
class FilenameBuilder(object):
|
|
"""Easily slice and dice filenames.
|
|
|
|
Initialize this class with an original file path, then use the fill()
|
|
method to create new filenames based on the original.
|
|
|
|
"""
|
|
MAX_FILENAME_LENGTH = 255 # VFAT's maximum filename length
|
|
|
|
def __init__(self, path):
|
|
"""Initialize a builder from an original file path."""
|
|
self.dirpath, self.basename = os.path.split(path)
|
|
self.basename, self.ext = os.path.splitext(self.basename)
|
|
self.ext = self.ext.lower()
|
|
|
|
def fill(self, fmtstr):
|
|
"""Build a new filename based on the original.
|
|
|
|
The fmtstr argument can include the following:
|
|
{basename} -- the original basename, with the extension removed
|
|
{ext} -- the original extension, always lowercase
|
|
|
|
If necessary, {basename} will be truncated so the filename does not
|
|
exceed this class' MAX_FILENAME_LENGTH in length.
|
|
|
|
"""
|
|
basename_len = (self.MAX_FILENAME_LENGTH -
|
|
len(fmtstr.format(basename='', ext=self.ext)))
|
|
return fmtstr.format(basename=self.basename[:basename_len],
|
|
ext=self.ext)
|
|
|
|
|
|
|
|
class MediaProcessor(object):
|
|
"""A particular processor for this media type.
|
|
|
|
While the ProcessingManager handles all types of MediaProcessing
|
|
possible for a particular media type, a MediaProcessor can be
|
|
thought of as a *particular* processing action for a media type.
|
|
For example, you may have separate MediaProcessors for:
|
|
|
|
- initial_processing: the intial processing of a media
|
|
- gen_thumb: generate a thumbnail
|
|
- resize: resize an image
|
|
- transcode: transcode a video
|
|
|
|
... etc.
|
|
|
|
Some information on producing a new MediaProcessor for your media type:
|
|
|
|
- You *must* supply a name attribute. This must be a class level
|
|
attribute, and a string. This will be used to determine the
|
|
subcommand of your process
|
|
- It's recommended that you supply a class level description
|
|
attribute.
|
|
- Supply a media_is_eligible classmethod. This will be used to
|
|
determine whether or not a media entry is eligible to use this
|
|
processor type. See the method documentation for details.
|
|
- To give "./bin/gmg reprocess run" abilities to this media type,
|
|
supply both gnerate_parser and parser_to_request classmethods.
|
|
- The process method will be what actually processes your media.
|
|
"""
|
|
# You MUST override this in the child MediaProcessor!
|
|
name = None
|
|
|
|
# Optional, but will be used in various places to describe the
|
|
# action this MediaProcessor provides
|
|
description = None
|
|
|
|
def __init__(self, manager):
|
|
self.manager = manager
|
|
|
|
# Should be initialized at time of processing, at least
|
|
self.workbench = None
|
|
|
|
# @with_workbench
|
|
def process(self, **kwargs):
|
|
"""
|
|
Actually process this media entry.
|
|
"""
|
|
raise NotImplementedError
|
|
|
|
@classmethod
|
|
def media_is_eligibile(self, media_entry):
|
|
raise NotImplementedError
|
|
|
|
###############################
|
|
# Command line interface things
|
|
###############################
|
|
|
|
@classmethod
|
|
def generate_parser(self):
|
|
raise NotImplementedError
|
|
|
|
@classmethod
|
|
def parser_to_request(self, parser):
|
|
raise NotImplementedError
|
|
|
|
##########################################
|
|
# THE FUTURE: web interface things here :)
|
|
##########################################
|
|
|
|
|
|
class ProcessingManager(object):
|
|
"""Manages all the processing actions available for a media type
|
|
|
|
Specific processing actions, MediaProcessor subclasses, are added
|
|
to the ProcessingManager.
|
|
"""
|
|
def __init__(self):
|
|
# Dict of all MediaProcessors of this media type
|
|
self.processors = {}
|
|
|
|
def add_processor(self, processor):
|
|
"""
|
|
Add a processor class to this media type
|
|
"""
|
|
name = processor.name
|
|
if name is None:
|
|
raise AttributeError("Processor class's .name attribute not set")
|
|
|
|
self.processors[name] = processor
|
|
|
|
def list_eligible_processors(self, entry):
|
|
"""
|
|
List all processors that this media entry is eligible to be processed
|
|
for.
|
|
"""
|
|
return [
|
|
processor
|
|
for processor in self.processors.keys()
|
|
if processor.media_is_eligible(entry)]
|
|
|
|
def gen_process_request_via_cli(self, subparser):
|
|
# Got to figure out what actually goes here before I can write this properly
|
|
pass
|
|
|
|
def process(self, entry, directive, request):
|
|
"""
|
|
Process a media entry.
|
|
"""
|
|
pass
|
|
|
|
|
|
class ProcessingState(object):
|
|
"""
|
|
The first and only argument to the "processor" of a media type
|
|
|
|
This could be thought of as a "request" to the processor
|
|
function. It has the main info for the request (media entry)
|
|
and a bunch of tools for the request on it.
|
|
It can get more fancy without impacting old media types.
|
|
"""
|
|
def __init__(self, entry):
|
|
self.entry = entry
|
|
self.workbench = None
|
|
self.orig_filename = None
|
|
|
|
def set_workbench(self, wb):
|
|
self.workbench = wb
|
|
|
|
def get_orig_filename(self):
|
|
"""
|
|
Get the a filename for the original, on local storage
|
|
|
|
If the media entry has a queued_media_file, use that, otherwise
|
|
use the original.
|
|
|
|
In the future, this will return the highest quality file available
|
|
if neither the original or queued file are available
|
|
"""
|
|
if self.orig_filename is not None:
|
|
return self.orig_filename
|
|
|
|
if self.entry.queued_media_file:
|
|
orig_filepath = self.entry.queued_media_file
|
|
storage = mgg.queue_store
|
|
else:
|
|
orig_filepath = self.entry.media_files['original']
|
|
storage = mgg.public_store
|
|
|
|
orig_filename = self.workbench.localized_file(
|
|
storage, orig_filepath,
|
|
'source')
|
|
self.orig_filename = orig_filename
|
|
return orig_filename
|
|
|
|
def copy_original(self, target_name, keyname=u"original"):
|
|
self.store_public(keyname, self.get_orig_filename(), target_name)
|
|
|
|
def store_public(self, keyname, local_file, target_name=None):
|
|
if target_name is None:
|
|
target_name = os.path.basename(local_file)
|
|
target_filepath = create_pub_filepath(self.entry, target_name)
|
|
if keyname in self.entry.media_files:
|
|
_log.warn("store_public: keyname %r already used for file %r, "
|
|
"replacing with %r", keyname,
|
|
self.entry.media_files[keyname], target_filepath)
|
|
mgg.public_store.copy_local_to_storage(local_file, target_filepath)
|
|
self.entry.media_files[keyname] = target_filepath
|
|
|
|
def delete_queue_file(self):
|
|
# Remove queued media file from storage and database.
|
|
# queued_filepath is in the task_id directory which should
|
|
# be removed too, but fail if the directory is not empty to be on
|
|
# the super-safe side.
|
|
queued_filepath = self.entry.queued_media_file
|
|
mgg.queue_store.delete_file(queued_filepath) # rm file
|
|
mgg.queue_store.delete_dir(queued_filepath[:-1]) # rm dir
|
|
self.entry.queued_media_file = []
|
|
|
|
|
|
def mark_entry_failed(entry_id, exc):
|
|
"""
|
|
Mark a media entry as having failed in its conversion.
|
|
|
|
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.
|
|
atomic_update(mgg.database.MediaEntry,
|
|
{'id': entry_id},
|
|
{u'state': u'failed',
|
|
u'fail_error': unicode(exc.exception_path),
|
|
u'fail_metadata': exc.metadata})
|
|
else:
|
|
_log.warn("No idea what happened here, but it failed: %r", exc)
|
|
# 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)
|
|
atomic_update(mgg.database.MediaEntry,
|
|
{'id': entry_id},
|
|
{u'state': u'failed',
|
|
u'fail_error': None,
|
|
u'fail_metadata': {}})
|
|
|
|
|
|
class BaseProcessingFail(Exception):
|
|
"""
|
|
Base exception that all other processing failure messages should
|
|
subclass from.
|
|
|
|
You shouldn't call this itself; instead you should subclass it
|
|
and provid the exception_path and general_message applicable to
|
|
this error.
|
|
"""
|
|
general_message = u''
|
|
|
|
@property
|
|
def exception_path(self):
|
|
return u"%s:%s" % (
|
|
self.__class__.__module__, self.__class__.__name__)
|
|
|
|
def __init__(self, **metadata):
|
|
self.metadata = metadata or {}
|
|
|
|
|
|
class BadMediaFail(BaseProcessingFail):
|
|
"""
|
|
Error that should be raised when an inappropriate file was given
|
|
for the media type specified.
|
|
"""
|
|
general_message = _(u'Invalid file given for media type.')
|