class ImageSimpleCache(ImageCache): """Simple image cache.""" def __init__(self, app=None): """Initialize the cache.""" super(ImageSimpleCache, self).__init__(app=app) self.cache = SimpleCache() def get(self, key): """Return the key value. :param key: the object's key :return: the stored object :rtype: `BytesIO` object """ return self.cache.get(key) def set(self, key, value, timeout=None): """Cache the object. :param key: the object's key :param value: the stored object :type value: `BytesIO` object :param timeout: the cache timeout in seconds """ timeout = timeout or self.timeout self.cache.set(key, value, timeout) self.set_last_modification(key, timeout=timeout) def get_last_modification(self, key): """Get last modification of cached file. :param key: the file object's key """ return self.get(self._last_modification_key_name(key)) def set_last_modification(self, key, last_modification=None, timeout=None): """Set last modification of cached file. :param key: the file object's key :param last_modification: Last modification date of file represented by the key :type last_modification: datetime.datetime :param timeout: the cache timeout in seconds """ if not last_modification: last_modification = datetime.utcnow().replace(microsecond=0) timeout = timeout or self.timeout self.cache.set(self._last_modification_key_name(key), last_modification, timeout) def delete(self, key): """Delete the specific key.""" self.cache.delete(key) self.cache.delete(self._last_modification_key_name(key)) def flush(self): """Flush the cache.""" self.cache.clear()
class RecacheTestCase(unittest.TestCase): def setUp(self): self.recached = False def dispatcher(salt): self.recached = True self.c = SimpleCache() cfg = Config(preemptive_recache_seconds=10, preemptive_recache_callback=dispatcher) self.s = Store(self.c, cfg) self.r = Retrieval(self.c, cfg) def test_preemptive_recaching_predicate(self): m = Metadata(HeaderSet(('foo', 'bar')), 'qux') def mkretr(**kwargs): return Retrieval(self.c, Config(**kwargs)) with a.test_request_context('/'): self.assertFalse( mkretr( preemptive_recache_seconds=10).should_recache_preemptively( 10, m)) self.assertFalse( mkretr(preemptive_recache_callback=lambda x: 0). should_recache_preemptively(10, m)) self.assertFalse(self.r.should_recache_preemptively(11, m)) self.assertTrue(self.r.should_recache_preemptively(10, m)) self.assertFalse(self.r.should_recache_preemptively(10, m)) self.c.clear() self.assertTrue(self.r.should_recache_preemptively(10, m)) def test_preemptive_recaching_cache_bypass(self): fresh = Response('foo') with a.test_request_context('/foo'): self.s.cache_response(fresh) metadata = self.r.fetch_metadata() with a.test_request_context('/foo'): cached = self.r.fetch_response() self.assertEquals(cached.headers[self.r.X_CACHE_HEADER], 'hit') with a.test_request_context('/foo', headers={RECACHE_HEADER: metadata.salt}): self.assertRaises(RecacheRequested, self.r.fetch_response) with a.test_request_context('/foo', headers={RECACHE_HEADER: 'incorrect-salt'}): try: self.r.fetch_response() except RecacheRequested: self.fail('unexpected RecacheRequested for incorrect salt')