youtube-dl/devscripts/make_lazy_extractors.py
Jaime Marquínez Ferrándiz 779822d945 Add experimental support for lazy loading the info extractors
'make lazy-extractors' creates the youtube_dl/extractor/lazy_extractors.py (imported by youtube_dl/extractor/__init__.py), which contains simplified classes that only have the 'suitable' class method and that load the appropiate class with the '__new__' method when a instance is created.
2016-04-08 21:50:07 +02:00

64 lines
1.7 KiB
Python

from __future__ import unicode_literals, print_function
from inspect import getsource
import os
from os.path import dirname as dirn
import sys
print('WARNING: Lazy loading extractors is an experimental feature that may not always work', file=sys.stderr)
sys.path.insert(0, dirn(dirn((os.path.abspath(__file__)))))
lazy_extractors_filename = sys.argv[1]
if os.path.exists(lazy_extractors_filename):
os.remove(lazy_extractors_filename)
from youtube_dl.extractor import _ALL_CLASSES
from youtube_dl.extractor.common import InfoExtractor
with open('devscripts/lazy_load_template.py', 'rt') as f:
module_template = f.read()
module_contents = [module_template + '\n' + getsource(InfoExtractor.suitable)]
ie_template = '''
class {name}(LazyLoadExtractor):
_VALID_URL = {valid_url!r}
_module = '{module}'
'''
make_valid_template = '''
@classmethod
def _make_valid_url(cls):
return {!r}
'''
def build_lazy_ie(ie, name):
valid_url = getattr(ie, '_VALID_URL', None)
s = ie_template.format(
name=name,
valid_url=valid_url,
module=ie.__module__)
if ie.suitable.__func__ is not InfoExtractor.suitable.__func__:
s += getsource(ie.suitable)
if hasattr(ie, '_make_valid_url'):
# search extractors
s += make_valid_template.format(ie._make_valid_url())
return s
names = []
for ie in _ALL_CLASSES:
name = ie.ie_key() + 'IE'
src = build_lazy_ie(ie, name)
module_contents.append(src)
names.append(name)
module_contents.append(
'_ALL_CLASSES = [{}]'.format(', '.join(names)))
module_src = '\n'.join(module_contents)
with open(lazy_extractors_filename, 'wt') as f:
f.write(module_src)