youtube-dl

Another place where youtube-dl lives on
git clone git://git.oshgnacknak.de/youtube-dl.git
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make_lazy_extractors.py (2872B)

      1 from __future__ import unicode_literals, print_function
      2 
      3 from inspect import getsource
      4 import io
      5 import os
      6 from os.path import dirname as dirn
      7 import sys
      8 
      9 print('WARNING: Lazy loading extractors is an experimental feature that may not always work', file=sys.stderr)
     10 
     11 sys.path.insert(0, dirn(dirn((os.path.abspath(__file__)))))
     12 
     13 lazy_extractors_filename = sys.argv[1]
     14 if os.path.exists(lazy_extractors_filename):
     15     os.remove(lazy_extractors_filename)
     16 
     17 from youtube_dl.extractor import _ALL_CLASSES
     18 from youtube_dl.extractor.common import InfoExtractor, SearchInfoExtractor
     19 
     20 with open('devscripts/lazy_load_template.py', 'rt') as f:
     21     module_template = f.read()
     22 
     23 module_contents = [
     24     module_template + '\n' + getsource(InfoExtractor.suitable) + '\n',
     25     'class LazyLoadSearchExtractor(LazyLoadExtractor):\n    pass\n']
     26 
     27 ie_template = '''
     28 class {name}({bases}):
     29     _VALID_URL = {valid_url!r}
     30     _module = '{module}'
     31 '''
     32 
     33 make_valid_template = '''
     34     @classmethod
     35     def _make_valid_url(cls):
     36         return {valid_url!r}
     37 '''
     38 
     39 
     40 def get_base_name(base):
     41     if base is InfoExtractor:
     42         return 'LazyLoadExtractor'
     43     elif base is SearchInfoExtractor:
     44         return 'LazyLoadSearchExtractor'
     45     else:
     46         return base.__name__
     47 
     48 
     49 def build_lazy_ie(ie, name):
     50     valid_url = getattr(ie, '_VALID_URL', None)
     51     s = ie_template.format(
     52         name=name,
     53         bases=', '.join(map(get_base_name, ie.__bases__)),
     54         valid_url=valid_url,
     55         module=ie.__module__)
     56     if ie.suitable.__func__ is not InfoExtractor.suitable.__func__:
     57         s += '\n' + getsource(ie.suitable)
     58     if hasattr(ie, '_make_valid_url'):
     59         # search extractors
     60         s += make_valid_template.format(valid_url=ie._make_valid_url())
     61     return s
     62 
     63 
     64 # find the correct sorting and add the required base classes so that subclasses
     65 # can be correctly created
     66 classes = _ALL_CLASSES[:-1]
     67 ordered_cls = []
     68 while classes:
     69     for c in classes[:]:
     70         bases = set(c.__bases__) - set((object, InfoExtractor, SearchInfoExtractor))
     71         stop = False
     72         for b in bases:
     73             if b not in classes and b not in ordered_cls:
     74                 if b.__name__ == 'GenericIE':
     75                     exit()
     76                 classes.insert(0, b)
     77                 stop = True
     78         if stop:
     79             break
     80         if all(b in ordered_cls for b in bases):
     81             ordered_cls.append(c)
     82             classes.remove(c)
     83             break
     84 ordered_cls.append(_ALL_CLASSES[-1])
     85 
     86 names = []
     87 for ie in ordered_cls:
     88     name = ie.__name__
     89     src = build_lazy_ie(ie, name)
     90     module_contents.append(src)
     91     if ie in _ALL_CLASSES:
     92         names.append(name)
     93 
     94 module_contents.append(
     95     '_ALL_CLASSES = [{0}]'.format(', '.join(names)))
     96 
     97 module_src = '\n'.join(module_contents) + '\n'
     98 
     99 with io.open(lazy_extractors_filename, 'wt', encoding='utf-8') as f:
    100     f.write(module_src)