sdk/python/tests/test_keep_client.py

   1 import hashlib
   2 import mock
   3 import os
   4 import re
   5 import socket
   6 import unittest
   7 import urlparse
   8
   9 import arvados
  10 import arvados.retry
  11 import arvados_testutil as tutil
  12 import run_test_server
  13
  14 class KeepTestCase(run_test_server.TestCaseWithServers):
  15     MAIN_SERVER = {}
  16     KEEP_SERVER = {}
  17
  18     @classmethod
  19     def setUpClass(cls):
  20         super(KeepTestCase, cls).setUpClass()
  21         run_test_server.authorize_with("admin")
  22         cls.api_client = arvados.api('v1')
  23         cls.keep_client = arvados.KeepClient(api_client=cls.api_client,
  24                                              proxy='', local_store='')
  25
  26     def test_KeepBasicRWTest(self):
  27         foo_locator = self.keep_client.put('foo')
  28         self.assertRegexpMatches(
  29             foo_locator,
  30             '^acbd18db4cc2f85cedef654fccc4a4d8\+3',
  31             'wrong md5 hash from Keep.put("foo"): ' + foo_locator)
  32         self.assertEqual(self.keep_client.get(foo_locator),
  33                          'foo',
  34                          'wrong content from Keep.get(md5("foo"))')
  35
  36     def test_KeepBinaryRWTest(self):
  37         blob_str = '\xff\xfe\xf7\x00\x01\x02'
  38         blob_locator = self.keep_client.put(blob_str)
  39         self.assertRegexpMatches(
  40             blob_locator,
  41             '^7fc7c53b45e53926ba52821140fef396\+6',
  42             ('wrong locator from Keep.put(<binarydata>):' + blob_locator))
  43         self.assertEqual(self.keep_client.get(blob_locator),
  44                          blob_str,
  45                          'wrong content from Keep.get(md5(<binarydata>))')
  46
  47     def test_KeepLongBinaryRWTest(self):
  48         blob_str = '\xff\xfe\xfd\xfc\x00\x01\x02\x03'
  49         for i in range(0,23):
  50             blob_str = blob_str + blob_str
  51         blob_locator = self.keep_client.put(blob_str)
  52         self.assertRegexpMatches(
  53             blob_locator,
  54             '^84d90fc0d8175dd5dcfab04b999bc956\+67108864',
  55             ('wrong locator from Keep.put(<binarydata>): ' + blob_locator))
  56         self.assertEqual(self.keep_client.get(blob_locator),
  57                          blob_str,
  58                          'wrong content from Keep.get(md5(<binarydata>))')
  59
  60     def test_KeepSingleCopyRWTest(self):
  61         blob_str = '\xff\xfe\xfd\xfc\x00\x01\x02\x03'
  62         blob_locator = self.keep_client.put(blob_str, copies=1)
  63         self.assertRegexpMatches(
  64             blob_locator,
  65             '^c902006bc98a3eb4a3663b65ab4a6fab\+8',
  66             ('wrong locator from Keep.put(<binarydata>): ' + blob_locator))
  67         self.assertEqual(self.keep_client.get(blob_locator),
  68                          blob_str,
  69                          'wrong content from Keep.get(md5(<binarydata>))')
  70
  71     def test_KeepEmptyCollectionTest(self):
  72         blob_locator = self.keep_client.put('', copies=1)
  73         self.assertRegexpMatches(
  74             blob_locator,
  75             '^d41d8cd98f00b204e9800998ecf8427e\+0',
  76             ('wrong locator from Keep.put(""): ' + blob_locator))
  77
  78
  79 class KeepPermissionTestCase(run_test_server.TestCaseWithServers):
  80     MAIN_SERVER = {}
  81     KEEP_SERVER = {'blob_signing_key': 'abcdefghijk0123456789',
  82                    'enforce_permissions': True}
  83
  84     def test_KeepBasicRWTest(self):
  85         run_test_server.authorize_with('active')
  86         keep_client = arvados.KeepClient()
  87         foo_locator = keep_client.put('foo')
  88         self.assertRegexpMatches(
  89             foo_locator,
  90             r'^acbd18db4cc2f85cedef654fccc4a4d8\+3\+A[a-f0-9]+@[a-f0-9]+$',
  91             'invalid locator from Keep.put("foo"): ' + foo_locator)
  92         self.assertEqual(keep_client.get(foo_locator),
  93                          'foo',
  94                          'wrong content from Keep.get(md5("foo"))')
  95
  96         # GET with an unsigned locator => NotFound
  97         bar_locator = keep_client.put('bar')
  98         unsigned_bar_locator = "37b51d194a7513e45b56f6524f2d51f2+3"
  99         self.assertRegexpMatches(
 100             bar_locator,
 101             r'^37b51d194a7513e45b56f6524f2d51f2\+3\+A[a-f0-9]+@[a-f0-9]+$',
 102             'invalid locator from Keep.put("bar"): ' + bar_locator)
 103         self.assertRaises(arvados.errors.NotFoundError,
 104                           keep_client.get,
 105                           unsigned_bar_locator)
 106
 107         # GET from a different user => NotFound
 108         run_test_server.authorize_with('spectator')
 109         self.assertRaises(arvados.errors.NotFoundError,
 110                           arvados.Keep.get,
 111                           bar_locator)
 112
 113         # Unauthenticated GET for a signed locator => NotFound
 114         # Unauthenticated GET for an unsigned locator => NotFound
 115         keep_client.api_token = ''
 116         self.assertRaises(arvados.errors.NotFoundError,
 117                           keep_client.get,
 118                           bar_locator)
 119         self.assertRaises(arvados.errors.NotFoundError,
 120                           keep_client.get,
 121                           unsigned_bar_locator)
 122
 123
 124 # KeepOptionalPermission: starts Keep with --permission-key-file
 125 # but not --enforce-permissions (i.e. generate signatures on PUT
 126 # requests, but do not require them for GET requests)
 127 #
 128 # All of these requests should succeed when permissions are optional:
 129 # * authenticated request, signed locator
 130 # * authenticated request, unsigned locator
 131 # * unauthenticated request, signed locator
 132 # * unauthenticated request, unsigned locator
 133 class KeepOptionalPermission(run_test_server.TestCaseWithServers):
 134     MAIN_SERVER = {}
 135     KEEP_SERVER = {'blob_signing_key': 'abcdefghijk0123456789',
 136                    'enforce_permissions': False}
 137
 138     @classmethod
 139     def setUpClass(cls):
 140         super(KeepOptionalPermission, cls).setUpClass()
 141         run_test_server.authorize_with("admin")
 142         cls.api_client = arvados.api('v1')
 143
 144     def setUp(self):
 145         super(KeepOptionalPermission, self).setUp()
 146         self.keep_client = arvados.KeepClient(api_client=self.api_client,
 147                                               proxy='', local_store='')
 148
 149     def _put_foo_and_check(self):
 150         signed_locator = self.keep_client.put('foo')
 151         self.assertRegexpMatches(
 152             signed_locator,
 153             r'^acbd18db4cc2f85cedef654fccc4a4d8\+3\+A[a-f0-9]+@[a-f0-9]+$',
 154             'invalid locator from Keep.put("foo"): ' + signed_locator)
 155         return signed_locator
 156
 157     def test_KeepAuthenticatedSignedTest(self):
 158         signed_locator = self._put_foo_and_check()
 159         self.assertEqual(self.keep_client.get(signed_locator),
 160                          'foo',
 161                          'wrong content from Keep.get(md5("foo"))')
 162
 163     def test_KeepAuthenticatedUnsignedTest(self):
 164         signed_locator = self._put_foo_and_check()
 165         self.assertEqual(self.keep_client.get("acbd18db4cc2f85cedef654fccc4a4d8"),
 166                          'foo',
 167                          'wrong content from Keep.get(md5("foo"))')
 168
 169     def test_KeepUnauthenticatedSignedTest(self):
 170         # Check that signed GET requests work even when permissions
 171         # enforcement is off.
 172         signed_locator = self._put_foo_and_check()
 173         self.keep_client.api_token = ''
 174         self.assertEqual(self.keep_client.get(signed_locator),
 175                          'foo',
 176                          'wrong content from Keep.get(md5("foo"))')
 177
 178     def test_KeepUnauthenticatedUnsignedTest(self):
 179         # Since --enforce-permissions is not in effect, GET requests
 180         # need not be authenticated.
 181         signed_locator = self._put_foo_and_check()
 182         self.keep_client.api_token = ''
 183         self.assertEqual(self.keep_client.get("acbd18db4cc2f85cedef654fccc4a4d8"),
 184                          'foo',
 185                          'wrong content from Keep.get(md5("foo"))')
 186
 187
 188 class KeepProxyTestCase(run_test_server.TestCaseWithServers):
 189     MAIN_SERVER = {}
 190     KEEP_SERVER = {}
 191     KEEP_PROXY_SERVER = {'auth': 'admin'}
 192
 193     @classmethod
 194     def setUpClass(cls):
 195         super(KeepProxyTestCase, cls).setUpClass()
 196         cls.api_client = arvados.api('v1')
 197
 198     def tearDown(self):
 199         arvados.config.settings().pop('ARVADOS_EXTERNAL_CLIENT', None)
 200         super(KeepProxyTestCase, self).tearDown()
 201
 202     def test_KeepProxyTest1(self):
 203         # Will use ARVADOS_KEEP_PROXY environment variable that is set by
 204         # setUpClass().
 205         keep_client = arvados.KeepClient(api_client=self.api_client,
 206                                          local_store='')
 207         baz_locator = keep_client.put('baz')
 208         self.assertRegexpMatches(
 209             baz_locator,
 210             '^73feffa4b7f6bb68e44cf984c85f6e88\+3',
 211             'wrong md5 hash from Keep.put("baz"): ' + baz_locator)
 212         self.assertEqual(keep_client.get(baz_locator),
 213                          'baz',
 214                          'wrong content from Keep.get(md5("baz"))')
 215         self.assertTrue(keep_client.using_proxy)
 216
 217     def test_KeepProxyTest2(self):
 218         # Don't instantiate the proxy directly, but set the X-External-Client
 219         # header.  The API server should direct us to the proxy.
 220         arvados.config.settings()['ARVADOS_EXTERNAL_CLIENT'] = 'true'
 221         keep_client = arvados.KeepClient(api_client=self.api_client,
 222                                          proxy='', local_store='')
 223         baz_locator = keep_client.put('baz2')
 224         self.assertRegexpMatches(
 225             baz_locator,
 226             '^91f372a266fe2bf2823cb8ec7fda31ce\+4',
 227             'wrong md5 hash from Keep.put("baz2"): ' + baz_locator)
 228         self.assertEqual(keep_client.get(baz_locator),
 229                          'baz2',
 230                          'wrong content from Keep.get(md5("baz2"))')
 231         self.assertTrue(keep_client.using_proxy)
 232
 233
 234 class KeepClientServiceTestCase(unittest.TestCase):
 235     def mock_keep_services(self, *services):
 236         api_client = mock.MagicMock(name='api_client')
 237         api_client.keep_services().accessible().execute.return_value = {
 238             'items_available': len(services),
 239             'items': [{
 240                     'uuid': 'zzzzz-bi6l4-{:015x}'.format(index),
 241                     'owner_uuid': 'zzzzz-tpzed-000000000000000',
 242                     'service_host': host,
 243                     'service_port': port,
 244                     'service_ssl_flag': ssl,
 245                     'service_type': servtype,
 246                     } for index, (host, port, ssl, servtype)
 247                       in enumerate(services)],
 248             }
 249         return api_client
 250
 251     def mock_n_keep_disks(self, service_count):
 252         return self.mock_keep_services(
 253             *[("keep0x{:x}".format(index), 80, False, 'disk')
 254               for index in range(service_count)])
 255
 256     def get_service_roots(self, *services):
 257         api_client = self.mock_keep_services(*services)
 258         keep_client = arvados.KeepClient(api_client=api_client)
 259         services = keep_client.weighted_service_roots('000000')
 260         return [urlparse.urlparse(url) for url in sorted(services)]
 261
 262     def test_ssl_flag_respected_in_roots(self):
 263         services = self.get_service_roots(('keep', 10, False, 'disk'),
 264                                           ('keep', 20, True, 'disk'))
 265         self.assertEqual(10, services[0].port)
 266         self.assertEqual('http', services[0].scheme)
 267         self.assertEqual(20, services[1].port)
 268         self.assertEqual('https', services[1].scheme)
 269
 270     def test_correct_ports_with_ipv6_addresses(self):
 271         service = self.get_service_roots(('100::1', 10, True, 'proxy'))[0]
 272         self.assertEqual('100::1', service.hostname)
 273         self.assertEqual(10, service.port)
 274
 275     # test_get_timeout and test_put_timeout test that
 276     # KeepClient.get and KeepClient.put use the appropriate timeouts
 277     # when connected directly to a Keep server (i.e. non-proxy timeout)
 278
 279     def test_get_timeout(self):
 280         api_client = self.mock_keep_services(('keep', 10, False, 'disk'))
 281         keep_client = arvados.KeepClient(api_client=api_client)
 282         force_timeout = [socket.timeout("timed out")]
 283         with mock.patch('requests.get', side_effect=force_timeout) as mock_request:
 284             with self.assertRaises(arvados.errors.KeepReadError):
 285                 keep_client.get('ffffffffffffffffffffffffffffffff')
 286             self.assertTrue(mock_request.called)
 287             self.assertEqual(
 288                 arvados.KeepClient.DEFAULT_TIMEOUT,
 289                 mock_request.call_args[1]['timeout'])
 290
 291     def test_put_timeout(self):
 292         api_client = self.mock_keep_services(('keep', 10, False, 'disk'))
 293         keep_client = arvados.KeepClient(api_client=api_client)
 294         force_timeout = [socket.timeout("timed out")]
 295         with mock.patch('requests.put', side_effect=force_timeout) as mock_request:
 296             with self.assertRaises(arvados.errors.KeepWriteError):
 297                 keep_client.put('foo')
 298             self.assertTrue(mock_request.called)
 299             self.assertEqual(
 300                 arvados.KeepClient.DEFAULT_TIMEOUT,
 301                 mock_request.call_args[1]['timeout'])
 302
 303     def test_proxy_get_timeout(self):
 304         # Force a timeout, verifying that the requests.get or
 305         # requests.put method was called with the proxy_timeout
 306         # setting rather than the default timeout.
 307         api_client = self.mock_keep_services(('keep', 10, False, 'proxy'))
 308         keep_client = arvados.KeepClient(api_client=api_client)
 309         force_timeout = [socket.timeout("timed out")]
 310         with mock.patch('requests.get', side_effect=force_timeout) as mock_request:
 311             with self.assertRaises(arvados.errors.KeepReadError):
 312                 keep_client.get('ffffffffffffffffffffffffffffffff')
 313             self.assertTrue(mock_request.called)
 314             self.assertEqual(
 315                 arvados.KeepClient.DEFAULT_PROXY_TIMEOUT,
 316                 mock_request.call_args[1]['timeout'])
 317
 318     def test_proxy_put_timeout(self):
 319         # Force a timeout, verifying that the requests.get or
 320         # requests.put method was called with the proxy_timeout
 321         # setting rather than the default timeout.
 322         api_client = self.mock_keep_services(('keep', 10, False, 'proxy'))
 323         keep_client = arvados.KeepClient(api_client=api_client)
 324         force_timeout = [socket.timeout("timed out")]
 325         with mock.patch('requests.put', side_effect=force_timeout) as mock_request:
 326             with self.assertRaises(arvados.errors.KeepWriteError):
 327                 keep_client.put('foo')
 328             self.assertTrue(mock_request.called)
 329             self.assertEqual(
 330                 arvados.KeepClient.DEFAULT_PROXY_TIMEOUT,
 331                 mock_request.call_args[1]['timeout'])
 332
 333     def test_probe_order_reference_set(self):
 334         # expected_order[i] is the probe order for
 335         # hash=md5(sprintf("%064x",i)) where there are 16 services
 336         # with uuid sprintf("anything-%015x",j) with j in 0..15. E.g.,
 337         # the first probe for the block consisting of 64 "0"
 338         # characters is the service whose uuid is
 339         # "zzzzz-bi6l4-000000000000003", so expected_order[0][0]=='3'.
 340         expected_order = [
 341             list('3eab2d5fc9681074'),
 342             list('097dba52e648f1c3'),
 343             list('c5b4e023f8a7d691'),
 344             list('9d81c02e76a3bf54'),
 345             ]
 346         hashes = [
 347             hashlib.md5("{:064x}".format(x)).hexdigest()
 348             for x in range(len(expected_order))]
 349         api_client = self.mock_n_keep_disks(16)
 350         keep_client = arvados.KeepClient(api_client=api_client)
 351         for i, hash in enumerate(hashes):
 352             roots = keep_client.weighted_service_roots(hash)
 353             got_order = [
 354                 re.search(r'//\[?keep0x([0-9a-f]+)', root).group(1)
 355                 for root in roots]
 356             self.assertEqual(expected_order[i], got_order)
 357
 358     def test_probe_waste_adding_one_server(self):
 359         hashes = [
 360             hashlib.md5("{:064x}".format(x)).hexdigest() for x in range(100)]
 361         initial_services = 12
 362         api_client = self.mock_n_keep_disks(initial_services)
 363         keep_client = arvados.KeepClient(api_client=api_client)
 364         probes_before = [
 365             keep_client.weighted_service_roots(hash) for hash in hashes]
 366         for added_services in range(1, 12):
 367             api_client = self.mock_n_keep_disks(initial_services+added_services)
 368             keep_client = arvados.KeepClient(api_client=api_client)
 369             total_penalty = 0
 370             for hash_index in range(len(hashes)):
 371                 probe_after = keep_client.weighted_service_roots(
 372                     hashes[hash_index])
 373                 penalty = probe_after.index(probes_before[hash_index][0])
 374                 self.assertLessEqual(penalty, added_services)
 375                 total_penalty += penalty
 376             # Average penalty per block should not exceed
 377             # N(added)/N(orig) by more than 20%, and should get closer
 378             # to the ideal as we add data points.
 379             expect_penalty = (
 380                 added_services *
 381                 len(hashes) / initial_services)
 382             max_penalty = (
 383                 expect_penalty *
 384                 (120 - added_services)/100)
 385             min_penalty = (
 386                 expect_penalty * 8/10)
 387             self.assertTrue(
 388                 min_penalty <= total_penalty <= max_penalty,
 389                 "With {}+{} services, {} blocks, penalty {} but expected {}..{}".format(
 390                     initial_services,
 391                     added_services,
 392                     len(hashes),
 393                     total_penalty,
 394                     min_penalty,
 395                     max_penalty))
 396
 397
 398 class KeepClientRetryTestMixin(object):
 399     # Testing with a local Keep store won't exercise the retry behavior.
 400     # Instead, our strategy is:
 401     # * Create a client with one proxy specified (pointed at a black
 402     #   hole), so there's no need to instantiate an API client, and
 403     #   all HTTP requests come from one place.
 404     # * Mock httplib's request method to provide simulated responses.
 405     # This lets us test the retry logic extensively without relying on any
 406     # supporting servers, and prevents side effects in case something hiccups.
 407     # To use this mixin, define DEFAULT_EXPECT, DEFAULT_EXCEPTION, and
 408     # run_method().
 409     #
 410     # Test classes must define TEST_PATCHER to a method that mocks
 411     # out appropriate methods in the client.
 412
 413     PROXY_ADDR = 'http://[%s]:65535/' % (tutil.TEST_HOST,)
 414     TEST_DATA = 'testdata'
 415     TEST_LOCATOR = 'ef654c40ab4f1747fc699915d4f70902+8'
 416
 417     def setUp(self):
 418         self.client_kwargs = {'proxy': self.PROXY_ADDR, 'local_store': ''}
 419
 420     def new_client(self, **caller_kwargs):
 421         kwargs = self.client_kwargs.copy()
 422         kwargs.update(caller_kwargs)
 423         return arvados.KeepClient(**kwargs)
 424
 425     def run_method(self, *args, **kwargs):
 426         raise NotImplementedError("test subclasses must define run_method")
 427
 428     def check_success(self, expected=None, *args, **kwargs):
 429         if expected is None:
 430             expected = self.DEFAULT_EXPECT
 431         self.assertEqual(expected, self.run_method(*args, **kwargs))
 432
 433     def check_exception(self, error_class=None, *args, **kwargs):
 434         if error_class is None:
 435             error_class = self.DEFAULT_EXCEPTION
 436         self.assertRaises(error_class, self.run_method, *args, **kwargs)
 437
 438     def test_immediate_success(self):
 439         with self.TEST_PATCHER(self.DEFAULT_EXPECT, 200):
 440             self.check_success()
 441
 442     def test_retry_then_success(self):
 443         with self.TEST_PATCHER(self.DEFAULT_EXPECT, 500, 200):
 444             self.check_success(num_retries=3)
 445
 446     def test_no_default_retry(self):
 447         with self.TEST_PATCHER(self.DEFAULT_EXPECT, 500, 200):
 448             self.check_exception()
 449
 450     def test_no_retry_after_permanent_error(self):
 451         with self.TEST_PATCHER(self.DEFAULT_EXPECT, 403, 200):
 452             self.check_exception(num_retries=3)
 453
 454     def test_error_after_retries_exhausted(self):
 455         with self.TEST_PATCHER(self.DEFAULT_EXPECT, 500, 500, 200):
 456             self.check_exception(num_retries=1)
 457
 458     def test_num_retries_instance_fallback(self):
 459         self.client_kwargs['num_retries'] = 3
 460         with self.TEST_PATCHER(self.DEFAULT_EXPECT, 500, 200):
 461             self.check_success()
 462
 463
 464 @tutil.skip_sleep
 465 class KeepClientRetryGetTestCase(KeepClientRetryTestMixin, unittest.TestCase):
 466     DEFAULT_EXPECT = KeepClientRetryTestMixin.TEST_DATA
 467     DEFAULT_EXCEPTION = arvados.errors.KeepReadError
 468     HINTED_LOCATOR = KeepClientRetryTestMixin.TEST_LOCATOR + '+K@xyzzy'
 469     TEST_PATCHER = staticmethod(tutil.mock_get_responses)
 470
 471     def run_method(self, locator=KeepClientRetryTestMixin.TEST_LOCATOR,
 472                    *args, **kwargs):
 473         return self.new_client().get(locator, *args, **kwargs)
 474
 475     def test_specific_exception_when_not_found(self):
 476         with tutil.mock_get_responses(self.DEFAULT_EXPECT, 404, 200):
 477             self.check_exception(arvados.errors.NotFoundError, num_retries=3)
 478
 479     def test_general_exception_with_mixed_errors(self):
 480         # get should raise a NotFoundError if no server returns the block,
 481         # and a high threshold of servers report that it's not found.
 482         # This test rigs up 50/50 disagreement between two servers, and
 483         # checks that it does not become a NotFoundError.
 484         client = self.new_client()
 485         with tutil.mock_get_responses(self.DEFAULT_EXPECT, 404, 500):
 486             with self.assertRaises(arvados.errors.KeepReadError) as exc_check:
 487                 client.get(self.HINTED_LOCATOR)
 488             self.assertNotIsInstance(
 489                 exc_check.exception, arvados.errors.NotFoundError,
 490                 "mixed errors raised NotFoundError")
 491
 492     def test_hint_server_can_succeed_without_retries(self):
 493         with tutil.mock_get_responses(self.DEFAULT_EXPECT, 404, 200, 500):
 494             self.check_success(locator=self.HINTED_LOCATOR)
 495
 496     def test_try_next_server_after_timeout(self):
 497         side_effects = [
 498             socket.timeout("timed out"),
 499             tutil.fake_requests_response(200, self.DEFAULT_EXPECT)]
 500         with mock.patch('requests.get',
 501                         side_effect=iter(side_effects)):
 502             self.check_success(locator=self.HINTED_LOCATOR)
 503
 504     def test_retry_data_with_wrong_checksum(self):
 505         side_effects = (tutil.fake_requests_response(200, s)
 506                         for s in ['baddata', self.TEST_DATA])
 507         with mock.patch('requests.get', side_effect=side_effects):
 508             self.check_success(locator=self.HINTED_LOCATOR)
 509
 510
 511 @tutil.skip_sleep
 512 class KeepClientRetryPutTestCase(KeepClientRetryTestMixin, unittest.TestCase):
 513     DEFAULT_EXPECT = KeepClientRetryTestMixin.TEST_LOCATOR
 514     DEFAULT_EXCEPTION = arvados.errors.KeepWriteError
 515     TEST_PATCHER = staticmethod(tutil.mock_put_responses)
 516
 517     def run_method(self, data=KeepClientRetryTestMixin.TEST_DATA,
 518                    copies=1, *args, **kwargs):
 519         return self.new_client().put(data, copies, *args, **kwargs)
 520
 521     def test_do_not_send_multiple_copies_to_same_server(self):
 522         with tutil.mock_put_responses(self.DEFAULT_EXPECT, 200):
 523             self.check_exception(copies=2, num_retries=3)