swift/test/unit/cli/test_manage_shard_ranges.py
Matthew Oliver 2641814010 Add sharder daemon, manage_shard_ranges tool and probe tests
The sharder daemon visits container dbs and when necessary executes
the sharding workflow on the db.

The workflow is, in overview:

- perform an audit of the container for sharding purposes.

- move any misplaced objects that do not belong in the container
  to their correct shard.

- move shard ranges from FOUND state to CREATED state by creating
  shard containers.

- move shard ranges from CREATED to CLEAVED state by cleaving objects
  to shard dbs and replicating those dbs. By default this is done in
  batches of 2 shard ranges per visit.

Additionally, when the auto_shard option is True (NOT yet recommeneded
in production), the sharder will identify shard ranges for containers
that have exceeded the threshold for sharding, and will also manage
the sharding and shrinking of shard containers.

The manage_shard_ranges tool provides a means to manually identify
shard ranges and merge them to a container in order to trigger
sharding. This is currently the recommended way to shard a container.

Co-Authored-By: Alistair Coles <alistairncoles@gmail.com>
Co-Authored-By: Tim Burke <tim.burke@gmail.com>
Co-Authored-By: Clay Gerrard <clay.gerrard@gmail.com>

Change-Id: I7f192209d4d5580f5a0aa6838f9f04e436cf6b1f
2018-05-18 18:48:13 +01:00

363 lines
16 KiB
Python

# Licensed under the Apache License, Version 2.0 (the "License"); you may not
# use this file except in compliance with the License. You may obtain a copy
# of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from __future__ import unicode_literals
import json
import os
import unittest
import mock
from shutil import rmtree
from tempfile import mkdtemp
from six.moves import cStringIO as StringIO
from swift.cli.manage_shard_ranges import main
from swift.common import utils
from swift.common.utils import Timestamp, ShardRange
from swift.container.backend import ContainerBroker
from test.unit import mock_timestamp_now
class TestManageShardRanges(unittest.TestCase):
def setUp(self):
self.testdir = os.path.join(mkdtemp(), 'tmp_test_cli_find_shards')
utils.mkdirs(self.testdir)
rmtree(self.testdir)
self.shard_data = [
{'index': 0, 'lower': '', 'upper': 'obj09', 'object_count': 10},
{'index': 1, 'lower': 'obj09', 'upper': 'obj19',
'object_count': 10},
{'index': 2, 'lower': 'obj19', 'upper': 'obj29',
'object_count': 10},
{'index': 3, 'lower': 'obj29', 'upper': 'obj39',
'object_count': 10},
{'index': 4, 'lower': 'obj39', 'upper': 'obj49',
'object_count': 10},
{'index': 5, 'lower': 'obj49', 'upper': 'obj59',
'object_count': 10},
{'index': 6, 'lower': 'obj59', 'upper': 'obj69',
'object_count': 10},
{'index': 7, 'lower': 'obj69', 'upper': 'obj79',
'object_count': 10},
{'index': 8, 'lower': 'obj79', 'upper': 'obj89',
'object_count': 10},
{'index': 9, 'lower': 'obj89', 'upper': '', 'object_count': 10},
]
def tearDown(self):
rmtree(os.path.dirname(self.testdir))
def assert_starts_with(self, value, prefix):
self.assertTrue(value.startswith(prefix),
"%r does not start with %r" % (value, prefix))
def assert_formatted_json(self, output, expected):
try:
loaded = json.loads(output)
except ValueError as err:
self.fail('Invalid JSON: %s\n%r' % (err, output))
# Check this one first, for a prettier diff
self.assertEqual(loaded, expected)
formatted = json.dumps(expected, sort_keys=True, indent=2) + '\n'
self.assertEqual(output, formatted)
def _make_broker(self, account='a', container='c',
device='sda', part=0):
datadir = os.path.join(
self.testdir, device, 'containers', str(part), 'ash', 'hash')
db_file = os.path.join(datadir, 'hash.db')
broker = ContainerBroker(
db_file, account=account, container=container)
broker.initialize()
return broker
def test_find_shard_ranges(self):
db_file = os.path.join(self.testdir, 'hash.db')
broker = ContainerBroker(db_file)
broker.account = 'a'
broker.container = 'c'
broker.initialize()
ts = utils.Timestamp.now()
broker.merge_items([
{'name': 'obj%02d' % i, 'created_at': ts.internal, 'size': 0,
'content_type': 'application/octet-stream', 'etag': 'not-really',
'deleted': 0, 'storage_policy_index': 0,
'ctype_timestamp': ts.internal, 'meta_timestamp': ts.internal}
for i in range(100)])
# Default uses a large enough value that sharding isn't required
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([db_file, 'find'])
self.assert_formatted_json(out.getvalue(), [])
err_lines = err.getvalue().split('\n')
self.assert_starts_with(err_lines[0], 'Loaded db broker for ')
self.assert_starts_with(err_lines[1], 'Found 0 ranges in ')
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([db_file, 'find', '100'])
self.assert_formatted_json(out.getvalue(), [])
err_lines = err.getvalue().split('\n')
self.assert_starts_with(err_lines[0], 'Loaded db broker for ')
self.assert_starts_with(err_lines[1], 'Found 0 ranges in ')
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([db_file, 'find', '99'])
self.assert_formatted_json(out.getvalue(), [
{'index': 0, 'lower': '', 'upper': 'obj98', 'object_count': 99},
{'index': 1, 'lower': 'obj98', 'upper': '', 'object_count': 1},
])
err_lines = err.getvalue().split('\n')
self.assert_starts_with(err_lines[0], 'Loaded db broker for ')
self.assert_starts_with(err_lines[1], 'Found 2 ranges in ')
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([db_file, 'find', '10'])
self.assert_formatted_json(out.getvalue(), [
{'index': 0, 'lower': '', 'upper': 'obj09', 'object_count': 10},
{'index': 1, 'lower': 'obj09', 'upper': 'obj19',
'object_count': 10},
{'index': 2, 'lower': 'obj19', 'upper': 'obj29',
'object_count': 10},
{'index': 3, 'lower': 'obj29', 'upper': 'obj39',
'object_count': 10},
{'index': 4, 'lower': 'obj39', 'upper': 'obj49',
'object_count': 10},
{'index': 5, 'lower': 'obj49', 'upper': 'obj59',
'object_count': 10},
{'index': 6, 'lower': 'obj59', 'upper': 'obj69',
'object_count': 10},
{'index': 7, 'lower': 'obj69', 'upper': 'obj79',
'object_count': 10},
{'index': 8, 'lower': 'obj79', 'upper': 'obj89',
'object_count': 10},
{'index': 9, 'lower': 'obj89', 'upper': '', 'object_count': 10},
])
err_lines = err.getvalue().split('\n')
self.assert_starts_with(err_lines[0], 'Loaded db broker for ')
self.assert_starts_with(err_lines[1], 'Found 10 ranges in ')
def test_info(self):
broker = self._make_broker()
broker.update_metadata({'X-Container-Sysmeta-Sharding':
(True, Timestamp.now().internal)})
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([broker.db_file, 'info'])
expected = ['Sharding enabled = True',
'Own shard range: None',
'db_state = unsharded',
'Metadata:',
' X-Container-Sysmeta-Sharding = True']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
retiring_db_id = broker.get_info()['id']
broker.merge_shard_ranges(ShardRange('.shards/cc', Timestamp.now()))
epoch = Timestamp.now()
with mock_timestamp_now(epoch) as now:
broker.enable_sharding(epoch)
self.assertTrue(broker.set_sharding_state())
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
with mock_timestamp_now(now):
main([broker.db_file, 'info'])
expected = ['Sharding enabled = True',
'Own shard range: {',
' "bytes_used": 0, ',
' "deleted": 0, ',
' "epoch": "%s", ' % epoch.internal,
' "lower": "", ',
' "meta_timestamp": "%s", ' % now.internal,
' "name": "a/c", ',
' "object_count": 0, ',
' "state": "sharding", ',
' "state_timestamp": "%s", ' % now.internal,
' "timestamp": "%s", ' % now.internal,
' "upper": ""',
'}',
'db_state = sharding',
'Retiring db id: %s' % retiring_db_id,
'Cleaving context: {',
' "cleave_to_row": null, ',
' "cleaving_done": false, ',
' "cursor": "", ',
' "last_cleave_to_row": null, ',
' "max_row": -1, ',
' "misplaced_done": false, ',
' "ranges_done": 0, ',
' "ranges_todo": 0, ',
' "ref": "%s"' % retiring_db_id,
'}',
'Metadata:',
' X-Container-Sysmeta-Sharding = True']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
self.assertTrue(broker.set_sharded_state())
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
with mock_timestamp_now(now):
main([broker.db_file, 'info'])
expected = ['Sharding enabled = True',
'Own shard range: {',
' "bytes_used": 0, ',
' "deleted": 0, ',
' "epoch": "%s", ' % epoch.internal,
' "lower": "", ',
' "meta_timestamp": "%s", ' % now.internal,
' "name": "a/c", ',
' "object_count": 0, ',
' "state": "sharding", ',
' "state_timestamp": "%s", ' % now.internal,
' "timestamp": "%s", ' % now.internal,
' "upper": ""',
'}',
'db_state = sharded',
'Metadata:',
' X-Container-Sysmeta-Sharding = True']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
def test_replace(self):
broker = self._make_broker()
broker.update_metadata({'X-Container-Sysmeta-Sharding':
(True, Timestamp.now().internal)})
input_file = os.path.join(self.testdir, 'shards')
with open(input_file, 'wb') as fd:
json.dump(self.shard_data, fd)
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([broker.db_file, 'replace', input_file])
expected = [
'No shard ranges found to delete.',
'Injected 10 shard ranges.',
'Run container-replicator to replicate them to other nodes.',
'Use the enable sub-command to enable sharding.']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
self.assertEqual(
[(data['lower'], data['upper']) for data in self.shard_data],
[(sr.lower_str, sr.upper_str) for sr in broker.get_shard_ranges()])
def _assert_enabled(self, broker, epoch):
own_sr = broker.get_own_shard_range()
self.assertEqual(ShardRange.SHARDING, own_sr.state)
self.assertEqual(epoch, own_sr.epoch)
self.assertEqual(ShardRange.MIN, own_sr.lower)
self.assertEqual(ShardRange.MAX, own_sr.upper)
self.assertEqual(
'True', broker.metadata['X-Container-Sysmeta-Sharding'][0])
def test_enable(self):
broker = self._make_broker()
broker.update_metadata({'X-Container-Sysmeta-Sharding':
(True, Timestamp.now().internal)})
# no shard ranges
out = StringIO()
err = StringIO()
with self.assertRaises(SystemExit):
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([broker.db_file, 'enable'])
expected = ["WARNING: invalid shard ranges: ['No shard ranges.'].",
'Aborting.']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
# success
shard_ranges = []
for data in self.shard_data:
path = ShardRange.make_path(
'.shards_a', 'c', 'c', Timestamp.now(), data['index'])
shard_ranges.append(
ShardRange(path, Timestamp.now(), data['lower'],
data['upper'], data['object_count']))
broker.merge_shard_ranges(shard_ranges)
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
with mock_timestamp_now() as now:
main([broker.db_file, 'enable'])
expected = [
"Container moved to state 'sharding' with epoch %s." %
now.internal,
'Run container-sharder on all nodes to shard the container.']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
self._assert_enabled(broker, now)
# already enabled
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
main([broker.db_file, 'enable'])
expected = [
"Container already in state 'sharding' with epoch %s." %
now.internal,
'No action required.',
'Run container-sharder on all nodes to shard the container.']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
self._assert_enabled(broker, now)
def test_find_replace_enable(self):
db_file = os.path.join(self.testdir, 'hash.db')
broker = ContainerBroker(db_file)
broker.account = 'a'
broker.container = 'c'
broker.initialize()
ts = utils.Timestamp.now()
broker.merge_items([
{'name': 'obj%02d' % i, 'created_at': ts.internal, 'size': 0,
'content_type': 'application/octet-stream', 'etag': 'not-really',
'deleted': 0, 'storage_policy_index': 0,
'ctype_timestamp': ts.internal, 'meta_timestamp': ts.internal}
for i in range(100)])
out = StringIO()
err = StringIO()
with mock.patch('sys.stdout', out), mock.patch('sys.stderr', err):
with mock_timestamp_now() as now:
main([broker.db_file, 'find_and_replace', '10', '--enable'])
expected = [
'No shard ranges found to delete.',
'Injected 10 shard ranges.',
'Run container-replicator to replicate them to other nodes.',
"Container moved to state 'sharding' with epoch %s." %
now.internal,
'Run container-sharder on all nodes to shard the container.']
self.assertEqual(expected, out.getvalue().splitlines())
self.assertEqual(['Loaded db broker for a/c.'],
err.getvalue().splitlines())
self._assert_enabled(broker, now)
self.assertEqual(
[(data['lower'], data['upper']) for data in self.shard_data],
[(sr.lower_str, sr.upper_str) for sr in broker.get_shard_ranges()])