From 218c423bc042674a8834ffc09520a94fbbe7b138 Mon Sep 17 00:00:00 2001 From: dirkf Date: Thu, 1 Sep 2022 13:28:30 +0100 Subject: [PATCH] [cache] Add cache validation by program version, based on yt-dlp --- test/test_cache.py | 16 ++++++++++++++-- youtube_dl/cache.py | 28 +++++++++++++++++++++++----- 2 files changed, 37 insertions(+), 7 deletions(-) diff --git a/test/test_cache.py b/test/test_cache.py index a16160142..931074aa1 100644 --- a/test/test_cache.py +++ b/test/test_cache.py @@ -3,17 +3,18 @@ from __future__ import unicode_literals -import shutil - # Allow direct execution import os import sys import unittest sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__)))) +import shutil from test.helper import FakeYDL from youtube_dl.cache import Cache +from youtube_dl.utils import version_tuple +from youtube_dl.version import __version__ def _is_empty(d): @@ -54,6 +55,17 @@ class TestCache(unittest.TestCase): self.assertFalse(os.path.exists(self.test_dir)) self.assertEqual(c.load('test_cache', 'k.'), None) + def test_cache_validation(self): + ydl = FakeYDL({ + 'cachedir': self.test_dir, + }) + c = Cache(ydl) + obj = {'x': 1, 'y': ['รค', '\\a', True]} + c.store('test_cache', 'k.', obj) + self.assertEqual(c.load('test_cache', 'k.', min_ver='1970.01.01'), obj) + new_version = '.'.join(('%d' % ((v + 1) if i == 0 else v, )) for i, v in enumerate(version_tuple(__version__))) + self.assertIs(c.load('test_cache', 'k.', min_ver=new_version), None) + if __name__ == '__main__': unittest.main() diff --git a/youtube_dl/cache.py b/youtube_dl/cache.py index 7bdade1bd..4822439d0 100644 --- a/youtube_dl/cache.py +++ b/youtube_dl/cache.py @@ -10,12 +10,21 @@ import traceback from .compat import compat_getenv from .utils import ( + error_to_compat_str, expand_path, + is_outdated_version, + try_get, write_json_file, ) +from .version import __version__ class Cache(object): + + _YTDL_DIR = 'youtube-dl' + _VERSION_KEY = _YTDL_DIR + '_version' + _DEFAULT_VERSION = '2021.12.17' + def __init__(self, ydl): self._ydl = ydl @@ -23,7 +32,7 @@ class Cache(object): res = self._ydl.params.get('cachedir') if res is None: cache_root = compat_getenv('XDG_CACHE_HOME', '~/.cache') - res = os.path.join(cache_root, 'youtube-dl') + res = os.path.join(cache_root, self._YTDL_DIR) return expand_path(res) def _get_cache_fn(self, section, key, dtype): @@ -50,13 +59,22 @@ class Cache(object): except OSError as ose: if ose.errno != errno.EEXIST: raise - write_json_file(data, fn) + write_json_file({self._VERSION_KEY: __version__, 'data': data}, fn) except Exception: tb = traceback.format_exc() self._ydl.report_warning( 'Writing cache to %r failed: %s' % (fn, tb)) - def load(self, section, key, dtype='json', default=None): + def _validate(self, data, min_ver): + version = try_get(data, lambda x: x[self._VERSION_KEY]) + if not version: # Backward compatibility + data, version = {'data': data}, self._DEFAULT_VERSION + if not is_outdated_version(version, min_ver or '0', assume_new=False): + return data['data'] + self._ydl.to_screen( + 'Discarding old cache from version {version} (needs {min_ver})'.format(**locals())) + + def load(self, section, key, dtype='json', default=None, min_ver=None): assert dtype in ('json',) if not self.enabled: @@ -66,12 +84,12 @@ class Cache(object): try: try: with io.open(cache_fn, 'r', encoding='utf-8') as cachef: - return json.load(cachef) + return self._validate(json.load(cachef), min_ver) except ValueError: try: file_size = os.path.getsize(cache_fn) except (OSError, IOError) as oe: - file_size = str(oe) + file_size = error_to_compat_str(oe) self._ydl.report_warning( 'Cache retrieval from %s failed (%s)' % (cache_fn, file_size)) except IOError: