yt_dlp/cache.py

   1 from __future__ import unicode_literals
   2
   3 import errno
   4 import io
   5 import json
   6 import os
   7 import re
   8 import shutil
   9 import traceback
  10
  11 from .compat import compat_getenv
  12 from .utils import (
  13     expand_path,
  14     write_json_file,
  15 )
  16
  17
  18 class Cache(object):
  19     def __init__(self, ydl):
  20         self._ydl = ydl
  21
  22     def _get_root_dir(self):
  23         res = self._ydl.params.get('cachedir')
  24         if res is None:
  25             cache_root = compat_getenv('XDG_CACHE_HOME', '~/.cache')
  26             res = os.path.join(cache_root, 'yt-dlp')
  27         return expand_path(res)
  28
  29     def _get_cache_fn(self, section, key, dtype):
  30         assert re.match(r'^[a-zA-Z0-9_.-]+$', section), \
  31             'invalid section %r' % section
  32         assert re.match(r'^[a-zA-Z0-9_.-]+$', key), 'invalid key %r' % key
  33         return os.path.join(
  34             self._get_root_dir(), section, '%s.%s' % (key, dtype))
  35
  36     @property
  37     def enabled(self):
  38         return self._ydl.params.get('cachedir') is not False
  39
  40     def store(self, section, key, data, dtype='json'):
  41         assert dtype in ('json',)
  42
  43         if not self.enabled:
  44             return
  45
  46         fn = self._get_cache_fn(section, key, dtype)
  47         try:
  48             try:
  49                 os.makedirs(os.path.dirname(fn))
  50             except OSError as ose:
  51                 if ose.errno != errno.EEXIST:
  52                     raise
  53             self._ydl.write_debug(f'Saving {section}.{key} to cache')
  54             write_json_file(data, fn)
  55         except Exception:
  56             tb = traceback.format_exc()
  57             self._ydl.report_warning(
  58                 'Writing cache to %r failed: %s' % (fn, tb))
  59
  60     def load(self, section, key, dtype='json', default=None):
  61         assert dtype in ('json',)
  62
  63         if not self.enabled:
  64             return default
  65
  66         cache_fn = self._get_cache_fn(section, key, dtype)
  67         try:
  68             try:
  69                 with io.open(cache_fn, 'r', encoding='utf-8') as cachef:
  70                     self._ydl.write_debug(f'Loading {section}.{key} from cache')
  71                     return json.load(cachef)
  72             except ValueError:
  73                 try:
  74                     file_size = os.path.getsize(cache_fn)
  75                 except (OSError, IOError) as oe:
  76                     file_size = str(oe)
  77                 self._ydl.report_warning(
  78                     'Cache retrieval from %s failed (%s)' % (cache_fn, file_size))
  79         except IOError:
  80             pass  # No cache available
  81
  82         return default
  83
  84     def remove(self):
  85         if not self.enabled:
  86             self._ydl.to_screen('Cache is disabled (Did you combine --no-cache-dir and --rm-cache-dir?)')
  87             return
  88
  89         cachedir = self._get_root_dir()
  90         if not any((term in cachedir) for term in ('cache', 'tmp')):
  91             raise Exception('Not removing directory %s - this does not look like a cache dir' % cachedir)
  92
  93         self._ydl.to_screen(
  94             'Removing cache dir %s .' % cachedir, skip_eol=True)
  95         if os.path.exists(cachedir):
  96             self._ydl.to_screen('.', skip_eol=True)
  97             shutil.rmtree(cachedir)
  98         self._ydl.to_screen('.')