yt_dlp/cache.py

   1 import contextlib
   2 import errno
   3 import json
   4 import os
   5 import re
   6 import shutil
   7 import traceback
   8
   9 from .utils import expand_path, write_json_file
  10
  11
  12 class Cache:
  13     def __init__(self, ydl):
  14         self._ydl = ydl
  15
  16     def _get_root_dir(self):
  17         res = self._ydl.params.get('cachedir')
  18         if res is None:
  19             cache_root = os.getenv('XDG_CACHE_HOME', '~/.cache')
  20             res = os.path.join(cache_root, 'yt-dlp')
  21         return expand_path(res)
  22
  23     def _get_cache_fn(self, section, key, dtype):
  24         assert re.match(r'^[a-zA-Z0-9_.-]+$', section), \
  25             'invalid section %r' % section
  26         assert re.match(r'^[a-zA-Z0-9_.-]+$', key), 'invalid key %r' % key
  27         return os.path.join(
  28             self._get_root_dir(), section, f'{key}.{dtype}')
  29
  30     @property
  31     def enabled(self):
  32         return self._ydl.params.get('cachedir') is not False
  33
  34     def store(self, section, key, data, dtype='json'):
  35         assert dtype in ('json',)
  36
  37         if not self.enabled:
  38             return
  39
  40         fn = self._get_cache_fn(section, key, dtype)
  41         try:
  42             try:
  43                 os.makedirs(os.path.dirname(fn))
  44             except OSError as ose:
  45                 if ose.errno != errno.EEXIST:
  46                     raise
  47             self._ydl.write_debug(f'Saving {section}.{key} to cache')
  48             write_json_file(data, fn)
  49         except Exception:
  50             tb = traceback.format_exc()
  51             self._ydl.report_warning(f'Writing cache to {fn!r} failed: {tb}')
  52
  53     def load(self, section, key, dtype='json', default=None):
  54         assert dtype in ('json',)
  55
  56         if not self.enabled:
  57             return default
  58
  59         cache_fn = self._get_cache_fn(section, key, dtype)
  60         with contextlib.suppress(OSError):
  61             try:
  62                 with open(cache_fn, encoding='utf-8') as cachef:
  63                     self._ydl.write_debug(f'Loading {section}.{key} from cache')
  64                     return json.load(cachef)
  65             except ValueError:
  66                 try:
  67                     file_size = os.path.getsize(cache_fn)
  68                 except OSError as oe:
  69                     file_size = str(oe)
  70                 self._ydl.report_warning(f'Cache retrieval from {cache_fn} failed ({file_size})')
  71
  72         return default
  73
  74     def remove(self):
  75         if not self.enabled:
  76             self._ydl.to_screen('Cache is disabled (Did you combine --no-cache-dir and --rm-cache-dir?)')
  77             return
  78
  79         cachedir = self._get_root_dir()
  80         if not any((term in cachedir) for term in ('cache', 'tmp')):
  81             raise Exception('Not removing directory %s - this does not look like a cache dir' % cachedir)
  82
  83         self._ydl.to_screen(
  84             'Removing cache dir %s .' % cachedir, skip_eol=True)
  85         if os.path.exists(cachedir):
  86             self._ydl.to_screen('.', skip_eol=True)
  87             shutil.rmtree(cachedir)
  88         self._ydl.to_screen('.')