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.
This commit is contained in:
Jaime Marquínez Ferrándiz 2016-02-10 14:01:31 +01:00
parent 1b3d5e05a8
commit 779822d945
5 changed files with 99 additions and 8 deletions

1
.gitignore vendored
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@ -13,6 +13,7 @@ README.txt
youtube-dl.1
youtube-dl.bash-completion
youtube-dl.fish
youtube_dl/extractor/lazy_extractors.py
youtube-dl
youtube-dl.exe
youtube-dl.tar.gz

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@ -1,7 +1,7 @@
all: youtube-dl README.md CONTRIBUTING.md README.txt youtube-dl.1 youtube-dl.bash-completion youtube-dl.zsh youtube-dl.fish supportedsites
clean:
rm -rf youtube-dl.1.temp.md youtube-dl.1 youtube-dl.bash-completion README.txt MANIFEST build/ dist/ .coverage cover/ youtube-dl.tar.gz youtube-dl.zsh youtube-dl.fish *.dump *.part *.info.json *.mp4 *.flv *.mp3 *.avi CONTRIBUTING.md.tmp ISSUE_TEMPLATE.md.tmp youtube-dl youtube-dl.exe
rm -rf youtube-dl.1.temp.md youtube-dl.1 youtube-dl.bash-completion README.txt MANIFEST build/ dist/ .coverage cover/ youtube-dl.tar.gz youtube-dl.zsh youtube-dl.fish youtube_dl/extractor/lazy_extractors.py *.dump *.part *.info.json *.mp4 *.flv *.mp3 *.avi CONTRIBUTING.md.tmp ISSUE_TEMPLATE.md.tmp youtube-dl youtube-dl.exe
find . -name "*.pyc" -delete
find . -name "*.class" -delete
@ -88,6 +88,12 @@ youtube-dl.fish: youtube_dl/*.py youtube_dl/*/*.py devscripts/fish-completion.in
fish-completion: youtube-dl.fish
lazy-extractors: youtube_dl/extractor/lazy_extractors.py
_EXTRACTOR_FILES != find youtube_dl/extractor -iname '*.py' -and -not -iname 'lazy_extractors.py'
youtube_dl/extractor/lazy_extractors.py: devscripts/make_lazy_extractors.py devscripts/lazy_load_template.py $(_EXTRACTOR_FILES)
$(PYTHON) devscripts/make_lazy_extractors.py $@
youtube-dl.tar.gz: youtube-dl README.md README.txt youtube-dl.1 youtube-dl.bash-completion youtube-dl.zsh youtube-dl.fish
@tar -czf youtube-dl.tar.gz --transform "s|^|youtube-dl/|" --owner 0 --group 0 \
--exclude '*.DS_Store' \

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@ -0,0 +1,17 @@
# flake8: noqa
from __future__ import unicode_literals
import re
class LazyLoadExtractor(object):
_module = None
@classmethod
def ie_key(cls):
return cls.__name__[:-2]
def __new__(cls):
mod = __import__(cls._module, fromlist=(cls.__name__,))
real_cls = getattr(mod, cls.__name__)
return real_cls.__new__(real_cls)

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@ -0,0 +1,63 @@
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)

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@ -1,13 +1,17 @@
from __future__ import unicode_literals
from .extractors import *
try:
from .lazy_extractors import *
from .lazy_extractors import _ALL_CLASSES
except ImportError:
from .extractors import *
_ALL_CLASSES = [
klass
for name, klass in globals().items()
if name.endswith('IE') and name != 'GenericIE'
]
_ALL_CLASSES.append(GenericIE)
_ALL_CLASSES = [
klass
for name, klass in globals().items()
if name.endswith('IE') and name != 'GenericIE'
]
_ALL_CLASSES.append(GenericIE)
def gen_extractor_classes():