feat(storage): full object checksum: implement rolling checksum and v… · googleapis/google-cloud-python@2361ba6

@@ -45,6 +45,48 @@ def test_initialization(self):

4545self.assertEqual(state.bytes_written, 0)4646self.assertEqual(state.next_expected_offset, initial_offset)4747self.assertFalse(state.is_complete)48+self.assertFalse(state.is_full_object_read)49+self.assertIsNone(state.rolling_checksum)50+51+def test_initialization_with_full_object_read(self):52+"""Test that _DownloadState initializes correctly when is_full_object_read is True."""53+initial_offset = 1054+initial_length = 10055+user_buffer = io.BytesIO()56+state_full = _DownloadState(57+initial_offset, initial_length, user_buffer, is_full_object_read=True58+ )59+60+self.assertEqual(state_full.initial_offset, initial_offset)61+self.assertEqual(state_full.initial_length, initial_length)62+self.assertEqual(state_full.user_buffer, user_buffer)63+self.assertEqual(state_full.bytes_written, 0)64+self.assertEqual(state_full.next_expected_offset, initial_offset)65+self.assertFalse(state_full.is_complete)66+self.assertTrue(state_full.is_full_object_read)67+self.assertIsNotNone(state_full.rolling_checksum)68+69+def test_initialization_with_full_object_read_and_checksum_disabled(self):70+"""Test that _DownloadState does not initialize rolling_checksum when enable_checksum is False."""71+initial_offset = 1072+initial_length = 10073+user_buffer = io.BytesIO()74+state_full = _DownloadState(75+initial_offset,76+initial_length,77+user_buffer,78+is_full_object_read=True,79+enable_checksum=False,80+ )81+82+self.assertEqual(state_full.initial_offset, initial_offset)83+self.assertEqual(state_full.initial_length, initial_length)84+self.assertEqual(state_full.user_buffer, user_buffer)85+self.assertEqual(state_full.bytes_written, 0)86+self.assertEqual(state_full.next_expected_offset, initial_offset)87+self.assertFalse(state_full.is_complete)88+self.assertTrue(state_full.is_full_object_read)89+self.assertIsNone(state_full.rolling_checksum)489049915092class TestReadResumptionStrategy(unittest.TestCase):

@@ -53,12 +95,24 @@ def setUp(self):

53955496self.state = {"download_states": {}, "read_handle": None, "routing_token": None}559756-def _add_download(self, read_id, offset=0, length=100, buffer=None):98+def _add_download(99+self,100+read_id,101+offset=0,102+length=100,103+buffer=None,104+is_full_object_read=False,105+enable_checksum=True,106+ ):57107"""Helper to inject a download state into the correct nested location."""58108if buffer is None:59109buffer = io.BytesIO()60110state = _DownloadState(61-initial_offset=offset, initial_length=length, user_buffer=buffer111+initial_offset=offset,112+initial_length=length,113+user_buffer=buffer,114+is_full_object_read=is_full_object_read,115+enable_checksum=enable_checksum,62116 )63117self.state["download_states"][read_id] = state64118return state

@@ -358,3 +412,61 @@ async def run():

358412359413# Token should remain unchanged360414self.assertEqual(self.state["routing_token"], "existing-token")415+416+def test_update_state_full_object_checksum_success(self):417+"""Test that full object checksum verification succeeds on range_end."""418+read_state = self._add_download(419+_READ_ID, offset=0, length=9, is_full_object_read=True420+ )421+self.state["enable_checksum"] = True422+self.state["full_obj_server_crc32c"] = google_crc32c.value(b"testdata1")423+424+resp1 = self._create_response(b"test", _READ_ID, offset=0)425+self.strategy.update_state_from_response(resp1, self.state)426+427+resp2 = self._create_response(b"data1", _READ_ID, offset=4, range_end=True)428+self.strategy.update_state_from_response(resp2, self.state)429+430+self.assertTrue(read_state.is_complete)431+self.assertEqual(read_state.bytes_written, 9)432+433+def test_update_state_full_object_checksum_failure(self):434+"""Test that full object checksum verification raises DataCorruption on mismatch at range_end."""435+self._add_download(_READ_ID, offset=0, length=9, is_full_object_read=True)436+self.state["enable_checksum"] = True437+self.state["full_obj_server_crc32c"] = 111111 # Wrong server checksum!438+439+resp1 = self._create_response(b"test", _READ_ID, offset=0)440+self.strategy.update_state_from_response(resp1, self.state)441+442+resp2 = self._create_response(b"data1", _READ_ID, offset=4, range_end=True)443+with self.assertRaisesRegex(DataCorruption, "Full object checksum mismatch"):444+self.strategy.update_state_from_response(resp2, self.state)445+446+def test_update_state_checksum_mismatch_ignored_when_disabled(self):447+"""Test that a CRC32C mismatch is ignored when enable_checksum is False."""448+self._add_download(_READ_ID)449+self.state["enable_checksum"] = False450+response = self._create_response(b"data", _READ_ID, offset=0, crc=999999)451+452+# Should NOT raise DataCorruption!453+self.strategy.update_state_from_response(response, self.state)454+455+def test_update_state_full_object_checksum_mismatch_ignored_when_disabled(self):456+"""Test that a full-object CRC32C mismatch is ignored when enable_checksum is False."""457+self._add_download(458+_READ_ID,459+offset=0,460+length=9,461+is_full_object_read=True,462+enable_checksum=False,463+ )464+self.state["enable_checksum"] = False465+self.state["full_obj_server_crc32c"] = 111111 # Wrong server checksum!466+467+resp1 = self._create_response(b"test", _READ_ID, offset=0)468+self.strategy.update_state_from_response(resp1, self.state)469+470+resp2 = self._create_response(b"data1", _READ_ID, offset=4, range_end=True)471+# Should NOT raise DataCorruption!472+self.strategy.update_state_from_response(resp2, self.state)