yt-dlc/devscripts/make_lazy_extractors.py

101 lines
2.8 KiB
Python

from __future__ import unicode_literals, print_function
from inspect import getsource
import io
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_dlc.extractor import _ALL_CLASSES
from youtube_dlc.extractor.common import InfoExtractor, SearchInfoExtractor
with open('devscripts/lazy_load_template.py', 'rt') as f:
module_template = f.read()
module_contents = [
module_template + '\n' + getsource(InfoExtractor.suitable) + '\n',
'class LazyLoadSearchExtractor(LazyLoadExtractor):\n pass\n']
ie_template = '''
class {name}({bases}):
_VALID_URL = {valid_url!r}
_module = '{module}'
'''
make_valid_template = '''
@classmethod
def _make_valid_url(cls):
return {valid_url!r}
'''
def get_base_name(base):
if base is InfoExtractor:
return 'LazyLoadExtractor'
elif base is SearchInfoExtractor:
return 'LazyLoadSearchExtractor'
else:
return base.__name__
def build_lazy_ie(ie, name):
valid_url = getattr(ie, '_VALID_URL', None)
s = ie_template.format(
name=name,
bases=', '.join(map(get_base_name, ie.__bases__)),
valid_url=valid_url,
module=ie.__module__)
if ie.suitable.__func__ is not InfoExtractor.suitable.__func__:
s += '\n' + getsource(ie.suitable)
if hasattr(ie, '_make_valid_url'):
# search extractors
s += make_valid_template.format(valid_url=ie._make_valid_url())
return s
# find the correct sorting and add the required base classes so that subclasses
# can be correctly created
classes = _ALL_CLASSES[:-1]
ordered_cls = []
while classes:
for c in classes[:]:
bases = set(c.__bases__) - set((object, InfoExtractor, SearchInfoExtractor))
stop = False
for b in bases:
if b not in classes and b not in ordered_cls:
if b.__name__ == 'GenericIE':
exit()
classes.insert(0, b)
stop = True
if stop:
break
if all(b in ordered_cls for b in bases):
ordered_cls.append(c)
classes.remove(c)
break
ordered_cls.append(_ALL_CLASSES[-1])
names = []
for ie in ordered_cls:
name = ie.__name__
src = build_lazy_ie(ie, name)
module_contents.append(src)
if ie in _ALL_CLASSES:
names.append(name)
module_contents.append(
'_ALL_CLASSES = [{0}]'.format(', '.join(names)))
module_src = '\n'.join(module_contents) + '\n'
with io.open(lazy_extractors_filename, 'wt', encoding='utf-8') as f:
f.write(module_src)