# Copyright 2013-present MongoDB, Inc.
#
# 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.

"""Test the mongo_client module."""

import contextlib
import copy
import datetime
import gc
import os
import signal
import socket
import struct
import sys
import time
import _thread as thread
import threading
import warnings

sys.path[0:0] = [""]

from bson import encode
from bson.codec_options import CodecOptions, TypeEncoder, TypeRegistry
from bson.son import SON
from bson.tz_util import utc
import pymongo
from pymongo import message, monitoring
from pymongo.common import CONNECT_TIMEOUT, _UUID_REPRESENTATIONS
from pymongo.command_cursor import CommandCursor
from pymongo.compression_support import _HAVE_SNAPPY, _HAVE_ZSTD
from pymongo.cursor import Cursor, CursorType
from pymongo.database import Database
from pymongo.errors import (AutoReconnect,
                            ConfigurationError,
                            ConnectionFailure,
                            InvalidName,
                            InvalidURI,
                            NetworkTimeout,
                            OperationFailure,
                            ServerSelectionTimeoutError,
                            WriteConcernError)
from pymongo.monitoring import (ServerHeartbeatListener,
                                ServerHeartbeatStartedEvent)
from pymongo.mongo_client import MongoClient
from pymongo.driver_info import DriverInfo
from pymongo.pool import SocketInfo, _METADATA
from pymongo.read_preferences import ReadPreference
from pymongo.server_description import ServerDescription
from pymongo.server_selectors import (readable_server_selector,
                                      writable_server_selector)
from pymongo.server_type import SERVER_TYPE
from pymongo.settings import TOPOLOGY_TYPE
from pymongo.topology import _ErrorContext
from pymongo.topology_description import TopologyDescription
from pymongo.srv_resolver import _HAVE_DNSPYTHON
from pymongo.write_concern import WriteConcern
from test import (client_context,
                  client_knobs,
                  SkipTest,
                  unittest,
                  IntegrationTest,
                  db_pwd,
                  db_user,
                  MockClientTest,
                  HAVE_IPADDRESS)
from test.pymongo_mocks import MockClient
from test.utils import (assertRaisesExactly,
                        connected,
                        CMAPListener,
                        delay,
                        FunctionCallRecorder,
                        get_pool,
                        gevent_monkey_patched,
                        is_greenthread_patched,
                        lazy_client_trial,
                        NTHREADS,
                        one,
                        remove_all_users,
                        rs_client,
                        rs_or_single_client,
                        rs_or_single_client_noauth,
                        single_client,
                        wait_until)


class ClientUnitTest(unittest.TestCase):
    """MongoClient tests that don't require a server."""

    @classmethod
    @client_context.require_connection
    def setUpClass(cls):
        cls.client = rs_or_single_client(connect=False,
                                         serverSelectionTimeoutMS=100)

    @classmethod
    def tearDownClass(cls):
        cls.client.close()

    def test_keyword_arg_defaults(self):
        client = MongoClient(socketTimeoutMS=None,
                             connectTimeoutMS=20000,
                             waitQueueTimeoutMS=None,
                             replicaSet=None,
                             read_preference=ReadPreference.PRIMARY,
                             ssl=False,
                             tlsCertificateKeyFile=None,
                             tlsAllowInvalidCertificates=True,  # ssl.CERT_NONE
                             tlsCAFile=None,
                             connect=False,
                             serverSelectionTimeoutMS=12000)

        options = client._MongoClient__options
        pool_opts = options.pool_options
        self.assertEqual(None, pool_opts.socket_timeout)
        # socket.Socket.settimeout takes a float in seconds
        self.assertEqual(20.0, pool_opts.connect_timeout)
        self.assertEqual(None, pool_opts.wait_queue_timeout)
        self.assertEqual(None, pool_opts.ssl_context)
        self.assertEqual(None, options.replica_set_name)
        self.assertEqual(ReadPreference.PRIMARY, client.read_preference)
        self.assertAlmostEqual(12, client.server_selection_timeout)

    def test_connect_timeout(self):
        client = MongoClient(connect=False, connectTimeoutMS=None,
                             socketTimeoutMS=None)
        pool_opts = client._MongoClient__options.pool_options
        self.assertEqual(None, pool_opts.socket_timeout)
        self.assertEqual(None, pool_opts.connect_timeout)
        client = MongoClient(connect=False, connectTimeoutMS=0,
                             socketTimeoutMS=0)
        pool_opts = client._MongoClient__options.pool_options
        self.assertEqual(None, pool_opts.socket_timeout)
        self.assertEqual(None, pool_opts.connect_timeout)
        client = MongoClient(
            'mongodb://localhost/?connectTimeoutMS=0&socketTimeoutMS=0',
            connect=False)
        pool_opts = client._MongoClient__options.pool_options
        self.assertEqual(None, pool_opts.socket_timeout)
        self.assertEqual(None, pool_opts.connect_timeout)

    def test_types(self):
        self.assertRaises(TypeError, MongoClient, 1)
        self.assertRaises(TypeError, MongoClient, 1.14)
        self.assertRaises(TypeError, MongoClient, "localhost", "27017")
        self.assertRaises(TypeError, MongoClient, "localhost", 1.14)
        self.assertRaises(TypeError, MongoClient, "localhost", [])

        self.assertRaises(ConfigurationError, MongoClient, [])

    def test_max_pool_size_zero(self):
        with self.assertRaises(ValueError):
            MongoClient(maxPoolSize=0)

    def test_uri_detection(self):
        self.assertRaises(
            ConfigurationError,
            MongoClient,
            "/foo")
        self.assertRaises(
            ConfigurationError,
            MongoClient,
            "://")
        self.assertRaises(
            ConfigurationError,
            MongoClient,
            "foo/")

    def test_get_db(self):
        def make_db(base, name):
            return base[name]

        self.assertRaises(InvalidName, make_db, self.client, "")
        self.assertRaises(InvalidName, make_db, self.client, "te$t")
        self.assertRaises(InvalidName, make_db, self.client, "te.t")
        self.assertRaises(InvalidName, make_db, self.client, "te\\t")
        self.assertRaises(InvalidName, make_db, self.client, "te/t")
        self.assertRaises(InvalidName, make_db, self.client, "te st")

        self.assertTrue(isinstance(self.client.test, Database))
        self.assertEqual(self.client.test, self.client["test"])
        self.assertEqual(self.client.test, Database(self.client, "test"))

    def test_get_database(self):
        codec_options = CodecOptions(tz_aware=True)
        write_concern = WriteConcern(w=2, j=True)
        db = self.client.get_database(
            'foo', codec_options, ReadPreference.SECONDARY, write_concern)
        self.assertEqual('foo', db.name)
        self.assertEqual(codec_options, db.codec_options)
        self.assertEqual(ReadPreference.SECONDARY, db.read_preference)
        self.assertEqual(write_concern, db.write_concern)

    def test_getattr(self):
        self.assertTrue(isinstance(self.client['_does_not_exist'], Database))

        with self.assertRaises(AttributeError) as context:
            self.client._does_not_exist

        # Message should be:
        # "AttributeError: MongoClient has no attribute '_does_not_exist'. To
        # access the _does_not_exist database, use client['_does_not_exist']".
        self.assertIn("has no attribute '_does_not_exist'",
                      str(context.exception))

    def test_iteration(self):
        def iterate():
            [a for a in self.client]

        self.assertRaises(TypeError, iterate)

    def test_get_default_database(self):
        c = rs_or_single_client("mongodb://%s:%d/foo" % (client_context.host,
                                                         client_context.port),
                                connect=False)
        self.assertEqual(Database(c, 'foo'), c.get_default_database())
        # Test that default doesn't override the URI value.
        self.assertEqual(Database(c, 'foo'), c.get_default_database('bar'))

        codec_options = CodecOptions(tz_aware=True)
        write_concern = WriteConcern(w=2, j=True)
        db = c.get_default_database(
            None, codec_options, ReadPreference.SECONDARY, write_concern)
        self.assertEqual('foo', db.name)
        self.assertEqual(codec_options, db.codec_options)
        self.assertEqual(ReadPreference.SECONDARY, db.read_preference)
        self.assertEqual(write_concern, db.write_concern)

        c = rs_or_single_client("mongodb://%s:%d/" % (client_context.host,
                                                      client_context.port),
                                connect=False)
        self.assertEqual(Database(c, 'foo'), c.get_default_database('foo'))

    def test_get_default_database_error(self):
        # URI with no database.
        c = rs_or_single_client("mongodb://%s:%d/" % (client_context.host,
                                                      client_context.port),
                                connect=False)
        self.assertRaises(ConfigurationError, c.get_default_database)

    def test_get_default_database_with_authsource(self):
        # Ensure we distinguish database name from authSource.
        uri = "mongodb://%s:%d/foo?authSource=src" % (
            client_context.host, client_context.port)
        c = rs_or_single_client(uri, connect=False)
        self.assertEqual(Database(c, 'foo'), c.get_default_database())

    def test_get_database_default(self):
        c = rs_or_single_client("mongodb://%s:%d/foo" % (client_context.host,
                                                         client_context.port),
                                connect=False)
        self.assertEqual(Database(c, 'foo'), c.get_database())

    def test_get_database_default_error(self):
        # URI with no database.
        c = rs_or_single_client("mongodb://%s:%d/" % (client_context.host,
                                                      client_context.port),
                                connect=False)
        self.assertRaises(ConfigurationError, c.get_database)

    def test_get_database_default_with_authsource(self):
        # Ensure we distinguish database name from authSource.
        uri = "mongodb://%s:%d/foo?authSource=src" % (
            client_context.host, client_context.port)
        c = rs_or_single_client(uri, connect=False)
        self.assertEqual(Database(c, 'foo'), c.get_database())

    def test_primary_read_pref_with_tags(self):
        # No tags allowed with "primary".
        with self.assertRaises(ConfigurationError):
            MongoClient('mongodb://host/?readpreferencetags=dc:east')

        with self.assertRaises(ConfigurationError):
            MongoClient('mongodb://host/?'
                        'readpreference=primary&readpreferencetags=dc:east')

    def test_read_preference(self):
        c = rs_or_single_client(
            "mongodb://host", connect=False,
            readpreference=ReadPreference.NEAREST.mongos_mode)
        self.assertEqual(c.read_preference, ReadPreference.NEAREST)

    def test_metadata(self):
        metadata = copy.deepcopy(_METADATA)
        metadata['application'] = {'name': 'foobar'}
        client = MongoClient(
            "mongodb://foo:27017/?appname=foobar&connect=false")
        options = client._MongoClient__options
        self.assertEqual(options.pool_options.metadata, metadata)
        client = MongoClient('foo', 27017, appname='foobar', connect=False)
        options = client._MongoClient__options
        self.assertEqual(options.pool_options.metadata, metadata)
        # No error
        MongoClient(appname='x' * 128)
        self.assertRaises(ValueError, MongoClient, appname='x' * 129)
        # Bad "driver" options.
        self.assertRaises(TypeError, DriverInfo, 'Foo', 1, 'a')
        self.assertRaises(TypeError, MongoClient, driver=1)
        self.assertRaises(TypeError, MongoClient, driver='abc')
        self.assertRaises(TypeError, MongoClient, driver=('Foo', '1', 'a'))
        # Test appending to driver info.
        metadata['driver']['name'] = 'PyMongo|FooDriver'
        metadata['driver']['version'] = '%s|1.2.3' % (
            _METADATA['driver']['version'],)
        client = MongoClient('foo', 27017, appname='foobar',
                             driver=DriverInfo('FooDriver', '1.2.3', None), connect=False)
        options = client._MongoClient__options
        self.assertEqual(options.pool_options.metadata, metadata)
        metadata['platform'] = '%s|FooPlatform' % (
            _METADATA['platform'],)
        client = MongoClient('foo', 27017, appname='foobar',
                             driver=DriverInfo('FooDriver', '1.2.3', 'FooPlatform'), connect=False)
        options = client._MongoClient__options
        self.assertEqual(options.pool_options.metadata, metadata)

    def test_kwargs_codec_options(self):
        class MyFloatType(object):
            def __init__(self, x):
                self.__x = x
            @property
            def x(self):
                return self.__x

        class MyFloatAsIntEncoder(TypeEncoder):
            python_type = MyFloatType
            def transform_python(self, value):
                return int(value)

        # Ensure codec options are passed in correctly
        document_class = SON
        type_registry = TypeRegistry([MyFloatAsIntEncoder()])
        tz_aware = True
        uuid_representation_label = 'javaLegacy'
        unicode_decode_error_handler = 'ignore'
        tzinfo = utc
        c = MongoClient(
            document_class=document_class,
            type_registry=type_registry,
            tz_aware=tz_aware,
            uuidrepresentation=uuid_representation_label,
            unicode_decode_error_handler=unicode_decode_error_handler,
            tzinfo=tzinfo,
            connect=False
        )

        self.assertEqual(c.codec_options.document_class, document_class)
        self.assertEqual(c.codec_options.type_registry, type_registry)
        self.assertEqual(c.codec_options.tz_aware, tz_aware)
        self.assertEqual(
            c.codec_options.uuid_representation,
            _UUID_REPRESENTATIONS[uuid_representation_label])
        self.assertEqual(
            c.codec_options.unicode_decode_error_handler,
            unicode_decode_error_handler)
        self.assertEqual(c.codec_options.tzinfo, tzinfo)

    def test_uri_codec_options(self):
        # Ensure codec options are passed in correctly
        uuid_representation_label = 'javaLegacy'
        unicode_decode_error_handler = 'ignore'
        uri = ("mongodb://%s:%d/foo?tz_aware=true&uuidrepresentation="
               "%s&unicode_decode_error_handler=%s" % (
                   client_context.host,
                   client_context.port,
                   uuid_representation_label,
                   unicode_decode_error_handler))
        c = MongoClient(uri, connect=False)

        self.assertEqual(c.codec_options.tz_aware, True)
        self.assertEqual(
            c.codec_options.uuid_representation,
            _UUID_REPRESENTATIONS[uuid_representation_label])
        self.assertEqual(
            c.codec_options.unicode_decode_error_handler,
            unicode_decode_error_handler)

    def test_uri_option_precedence(self):
        # Ensure kwarg options override connection string options.
        uri = ("mongodb://localhost/?ssl=true&replicaSet=name"
               "&readPreference=primary")
        c = MongoClient(uri, ssl=False, replicaSet="newname",
                        readPreference="secondaryPreferred")
        clopts = c._MongoClient__options
        opts = clopts._options

        self.assertEqual(opts['tls'], False)
        self.assertEqual(clopts.replica_set_name, "newname")
        self.assertEqual(
            clopts.read_preference, ReadPreference.SECONDARY_PREFERRED)

    @unittest.skipUnless(
        _HAVE_DNSPYTHON, "DNS-related tests need dnspython to be installed")
    def test_connection_timeout_ms_propagates_to_DNS_resolver(self):
        # Patch the resolver.
        from pymongo.srv_resolver import _resolve
        patched_resolver = FunctionCallRecorder(_resolve)
        pymongo.srv_resolver._resolve = patched_resolver
        def reset_resolver():
            pymongo.srv_resolver._resolve = _resolve
        self.addCleanup(reset_resolver)

        # Setup.
        base_uri = "mongodb+srv://test5.test.build.10gen.cc"
        connectTimeoutMS = 5000
        expected_kw_value = 5.0
        uri_with_timeout = base_uri + "/?connectTimeoutMS=6000"
        expected_uri_value = 6.0

        def test_scenario(args, kwargs, expected_value):
            patched_resolver.reset()
            MongoClient(*args, **kwargs)
            for _, kw in patched_resolver.call_list():
                self.assertAlmostEqual(kw['lifetime'], expected_value)

        # No timeout specified.
        test_scenario((base_uri,), {}, CONNECT_TIMEOUT)

        # Timeout only specified in connection string.
        test_scenario((uri_with_timeout,), {}, expected_uri_value)

        # Timeout only specified in keyword arguments.
        kwarg = {'connectTimeoutMS': connectTimeoutMS}
        test_scenario((base_uri,), kwarg, expected_kw_value)

        # Timeout specified in both kwargs and connection string.
        test_scenario((uri_with_timeout,), kwarg, expected_kw_value)

    def test_uri_security_options(self):
        # Ensure that we don't silently override security-related options.
        with self.assertRaises(InvalidURI):
            MongoClient('mongodb://localhost/?ssl=true', tls=False,
                        connect=False)

        # Matching SSL and TLS options should not cause errors.
        c = MongoClient('mongodb://localhost/?ssl=false', tls=False,
                        connect=False)
        self.assertEqual(c._MongoClient__options._options['tls'], False)

        # Conflicting tlsInsecure options should raise an error.
        with self.assertRaises(InvalidURI):
            MongoClient('mongodb://localhost/?tlsInsecure=true',
                        connect=False, tlsAllowInvalidHostnames=True)

        # Conflicting legacy tlsInsecure options should also raise an error.
        with self.assertRaises(InvalidURI):
            MongoClient('mongodb://localhost/?tlsInsecure=true',
                        connect=False, tlsAllowInvalidCertificates=False)

        # Conflicting kwargs should raise InvalidURI
        with self.assertRaises(InvalidURI):
            MongoClient(ssl=True, tls=False)


class TestClient(IntegrationTest):

    def test_max_idle_time_reaper_default(self):
        with client_knobs(kill_cursor_frequency=0.1):
            # Assert reaper doesn't remove sockets when maxIdleTimeMS not set
            client = rs_or_single_client()
            server = client._get_topology().select_server(
                readable_server_selector)
            with server._pool.get_socket({}) as sock_info:
                pass
            self.assertEqual(1, len(server._pool.sockets))
            self.assertTrue(sock_info in server._pool.sockets)
            client.close()

    def test_max_idle_time_reaper_removes_stale_minPoolSize(self):
        with client_knobs(kill_cursor_frequency=0.1):
            # Assert reaper removes idle socket and replaces it with a new one
            client = rs_or_single_client(maxIdleTimeMS=500,
                                         minPoolSize=1)
            server = client._get_topology().select_server(
                readable_server_selector)
            with server._pool.get_socket({}) as sock_info:
                pass
            # When the reaper runs at the same time as the get_socket, two
            # sockets could be created and checked into the pool.
            self.assertGreaterEqual(len(server._pool.sockets), 1)
            wait_until(lambda: sock_info not in server._pool.sockets,
                       "remove stale socket")
            wait_until(lambda: 1 <= len(server._pool.sockets),
                       "replace stale socket")
            client.close()

    def test_max_idle_time_reaper_does_not_exceed_maxPoolSize(self):
        with client_knobs(kill_cursor_frequency=0.1):
            # Assert reaper respects maxPoolSize when adding new sockets.
            client = rs_or_single_client(maxIdleTimeMS=500,
                                         minPoolSize=1,
                                         maxPoolSize=1)
            server = client._get_topology().select_server(
                readable_server_selector)
            with server._pool.get_socket({}) as sock_info:
                pass
            # When the reaper runs at the same time as the get_socket,
            # maxPoolSize=1 should prevent two sockets from being created.
            self.assertEqual(1, len(server._pool.sockets))
            wait_until(lambda: sock_info not in server._pool.sockets,
                       "remove stale socket")
            wait_until(lambda: 1 == len(server._pool.sockets),
                       "replace stale socket")
            client.close()

    def test_max_idle_time_reaper_removes_stale(self):
        with client_knobs(kill_cursor_frequency=0.1):
            # Assert reaper has removed idle socket and NOT replaced it
            client = rs_or_single_client(maxIdleTimeMS=500)
            server = client._get_topology().select_server(
                readable_server_selector)
            with server._pool.get_socket({}) as sock_info_one:
                pass
            # Assert that the pool does not close sockets prematurely.
            time.sleep(.300)
            with server._pool.get_socket({}) as sock_info_two:
                pass
            self.assertIs(sock_info_one, sock_info_two)
            wait_until(
                lambda: 0 == len(server._pool.sockets),
                "stale socket reaped and new one NOT added to the pool")
            client.close()

    def test_min_pool_size(self):
        with client_knobs(kill_cursor_frequency=.1):
            client = rs_or_single_client()
            server = client._get_topology().select_server(
                readable_server_selector)
            self.assertEqual(0, len(server._pool.sockets))

            # Assert that pool started up at minPoolSize
            client = rs_or_single_client(minPoolSize=10)
            server = client._get_topology().select_server(
                readable_server_selector)
            wait_until(lambda: 10 == len(server._pool.sockets),
                       "pool initialized with 10 sockets")

            # Assert that if a socket is closed, a new one takes its place
            with server._pool.get_socket({}) as sock_info:
                sock_info.close_socket(None)
            wait_until(lambda: 10 == len(server._pool.sockets),
                       "a closed socket gets replaced from the pool")
            self.assertFalse(sock_info in server._pool.sockets)

    def test_max_idle_time_checkout(self):
        # Use high frequency to test _get_socket_no_auth.
        with client_knobs(kill_cursor_frequency=99999999):
            client = rs_or_single_client(maxIdleTimeMS=500)
            server = client._get_topology().select_server(
                readable_server_selector)
            with server._pool.get_socket({}) as sock_info:
                pass
            self.assertEqual(1, len(server._pool.sockets))
            time.sleep(1) #  Sleep so that the socket becomes stale.

            with server._pool.get_socket({}) as new_sock_info:
                self.assertNotEqual(sock_info, new_sock_info)
            self.assertEqual(1, len(server._pool.sockets))
            self.assertFalse(sock_info in server._pool.sockets)
            self.assertTrue(new_sock_info in server._pool.sockets)

            # Test that sockets are reused if maxIdleTimeMS is not set.
            client = rs_or_single_client()
            server = client._get_topology().select_server(
                readable_server_selector)
            with server._pool.get_socket({}) as sock_info:
                pass
            self.assertEqual(1, len(server._pool.sockets))
            time.sleep(1)
            with server._pool.get_socket({}) as new_sock_info:
                self.assertEqual(sock_info, new_sock_info)
            self.assertEqual(1, len(server._pool.sockets))

    def test_constants(self):
        """This test uses MongoClient explicitly to make sure that host and
        port are not overloaded.
        """
        host, port = client_context.host, client_context.port
        kwargs = client_context.default_client_options.copy()
        if client_context.auth_enabled:
            kwargs['username'] = db_user
            kwargs['password'] = db_pwd

        # Set bad defaults.
        MongoClient.HOST = "somedomainthatdoesntexist.org"
        MongoClient.PORT = 123456789
        with self.assertRaises(AutoReconnect):
            connected(MongoClient(serverSelectionTimeoutMS=10,
                                  **kwargs))

        # Override the defaults. No error.
        connected(MongoClient(host, port, **kwargs))

        # Set good defaults.
        MongoClient.HOST = host
        MongoClient.PORT = port

        # No error.
        connected(MongoClient(**kwargs))

    def test_init_disconnected(self):
        host, port = client_context.host, client_context.port
        c = rs_or_single_client(connect=False)
        # is_primary causes client to block until connected
        self.assertIsInstance(c.is_primary, bool)

        c = rs_or_single_client(connect=False)
        self.assertIsInstance(c.is_mongos, bool)
        c = rs_or_single_client(connect=False)
        self.assertIsInstance(c.max_pool_size, int)
        self.assertIsInstance(c.nodes, frozenset)

        c = rs_or_single_client(connect=False)
        self.assertEqual(c.codec_options, CodecOptions())
        self.assertIsInstance(c.max_bson_size, int)
        c = rs_or_single_client(connect=False)
        self.assertFalse(c.primary)
        self.assertFalse(c.secondaries)
        c = rs_or_single_client(connect=False)
        self.assertIsInstance(c.max_write_batch_size, int)
        self.assertIsInstance(c.topology_description, TopologyDescription)
        self.assertEqual(c.topology_description, c._topology._description)

        if client_context.is_rs:
            # The primary's host and port are from the replica set config.
            self.assertIsNotNone(c.address)
        else:
            self.assertEqual(c.address, (host, port))

        bad_host = "somedomainthatdoesntexist.org"
        c = MongoClient(bad_host, port, connectTimeoutMS=1,
                        serverSelectionTimeoutMS=10)
        self.assertRaises(ConnectionFailure, c.pymongo_test.test.find_one)

    def test_init_disconnected_with_auth(self):
        uri = "mongodb://user:pass@somedomainthatdoesntexist"
        c = MongoClient(uri, connectTimeoutMS=1,
                        serverSelectionTimeoutMS=10)
        self.assertRaises(ConnectionFailure, c.pymongo_test.test.find_one)

    def test_equality(self):
        c = connected(rs_or_single_client())
        self.assertEqual(client_context.client, c)

        # Explicitly test inequality
        self.assertFalse(client_context.client != c)

    def test_hashable(self):
        c = connected(rs_or_single_client())
        self.assertIn(c, {client_context.client})

    def test_host_w_port(self):
        with self.assertRaises(ValueError):
            connected(MongoClient("%s:1234567" % (client_context.host,),
                                  connectTimeoutMS=1,
                                  serverSelectionTimeoutMS=10))

    def test_repr(self):
        # Used to test 'eval' below.
        import bson

        client = MongoClient(
            'mongodb://localhost:27017,localhost:27018/?replicaSet=replset'
            '&connectTimeoutMS=12345&w=1&wtimeoutms=100',
            connect=False, document_class=SON)

        the_repr = repr(client)
        self.assertIn('MongoClient(host=', the_repr)
        self.assertIn(
            "document_class=bson.son.SON, "
            "tz_aware=False, "
            "connect=False, ",
            the_repr)
        self.assertIn("connecttimeoutms=12345", the_repr)
        self.assertIn("replicaset='replset'", the_repr)
        self.assertIn("w=1", the_repr)
        self.assertIn("wtimeoutms=100", the_repr)

        self.assertEqual(eval(the_repr), client)

        client = MongoClient("localhost:27017,localhost:27018",
                             replicaSet='replset',
                             connectTimeoutMS=12345,
                             socketTimeoutMS=None,
                             w=1,
                             wtimeoutms=100,
                             connect=False)
        the_repr = repr(client)
        self.assertIn('MongoClient(host=', the_repr)
        self.assertIn(
            "document_class=dict, "
            "tz_aware=False, "
            "connect=False, ",
            the_repr)
        self.assertIn("connecttimeoutms=12345", the_repr)
        self.assertIn("replicaset='replset'", the_repr)
        self.assertIn("sockettimeoutms=None", the_repr)
        self.assertIn("w=1", the_repr)
        self.assertIn("wtimeoutms=100", the_repr)

        self.assertEqual(eval(the_repr), client)

    def test_getters(self):
        wait_until(lambda: client_context.nodes == self.client.nodes,
                   "find all nodes")

    def test_list_databases(self):
        cmd_docs = self.client.admin.command('listDatabases')['databases']
        cursor = self.client.list_databases()
        self.assertIsInstance(cursor, CommandCursor)
        helper_docs = list(cursor)
        self.assertTrue(len(helper_docs) > 0)
        self.assertEqual(helper_docs, cmd_docs)
        for doc in helper_docs:
            self.assertIs(type(doc), dict)
        client = rs_or_single_client(document_class=SON)
        for doc in client.list_databases():
            self.assertIs(type(doc), dict)

        if client_context.version.at_least(3, 4, 2):
            self.client.pymongo_test.test.insert_one({})
            cursor = self.client.list_databases(filter={"name": "admin"})
            docs = list(cursor)
            self.assertEqual(1, len(docs))
            self.assertEqual(docs[0]["name"], "admin")

        if client_context.version.at_least(3, 4, 3):
            cursor = self.client.list_databases(nameOnly=True)
            for doc in cursor:
                self.assertEqual(["name"], list(doc))

    def test_list_database_names(self):
        self.client.pymongo_test.test.insert_one({"dummy": "object"})
        self.client.pymongo_test_mike.test.insert_one({"dummy": "object"})
        cmd_docs = self.client.admin.command("listDatabases")["databases"]
        cmd_names = [doc["name"] for doc in cmd_docs]

        db_names = self.client.list_database_names()
        self.assertTrue("pymongo_test" in db_names)
        self.assertTrue("pymongo_test_mike" in db_names)
        self.assertEqual(db_names, cmd_names)

    def test_drop_database(self):
        self.assertRaises(TypeError, self.client.drop_database, 5)
        self.assertRaises(TypeError, self.client.drop_database, None)

        self.client.pymongo_test.test.insert_one({"dummy": "object"})
        self.client.pymongo_test2.test.insert_one({"dummy": "object"})
        dbs = self.client.list_database_names()
        self.assertIn("pymongo_test", dbs)
        self.assertIn("pymongo_test2", dbs)
        self.client.drop_database("pymongo_test")

        if client_context.version.at_least(3, 3, 9) and client_context.is_rs:
            wc_client = rs_or_single_client(w=len(client_context.nodes) + 1)
            with self.assertRaises(WriteConcernError):
                wc_client.drop_database('pymongo_test2')

        self.client.drop_database(self.client.pymongo_test2)

        raise SkipTest("This test often fails due to SERVER-2329")

        dbs = self.client.list_database_names()
        self.assertNotIn("pymongo_test", dbs)
        self.assertNotIn("pymongo_test2", dbs)

    def test_close(self):
        coll = self.client.pymongo_test.bar

        self.client.close()
        self.client.close()

        coll.count_documents({})

        self.client.close()
        self.client.close()

        coll.count_documents({})

    def test_close_kills_cursors(self):
        if sys.platform.startswith('java'):
            # We can't figure out how to make this test reliable with Jython.
            raise SkipTest("Can't test with Jython")
        # Kill any cursors possibly queued up by previous tests.
        gc.collect()
        self.client._process_periodic_tasks()

        # Add some test data.
        coll = self.client.pymongo_test.test_close_kills_cursors
        docs_inserted = 1000
        coll.insert_many([{"i": i} for i in range(docs_inserted)])

        # Open a cursor and leave it open on the server.
        cursor = coll.find().batch_size(10)
        self.assertTrue(bool(next(cursor)))
        self.assertLess(cursor.retrieved, docs_inserted)

        # Open a command cursor and leave it open on the server.
        cursor = coll.aggregate([], batchSize=10)
        self.assertTrue(bool(next(cursor)))
        del cursor
        # Required for PyPy, Jython and other Python implementations that
        # don't use reference counting garbage collection.
        gc.collect()

        # Close the client and ensure the topology is closed.
        self.assertTrue(self.client._topology._opened)
        self.client.close()
        self.assertFalse(self.client._topology._opened)

        # The killCursors task should not need to re-open the topology.
        self.client._process_periodic_tasks()
        self.assertFalse(self.client._topology._opened)

    def test_close_stops_kill_cursors_thread(self):
        client = rs_client()
        client.test.test.find_one()
        self.assertFalse(client._kill_cursors_executor._stopped)

        # Closing the client should stop the thread.
        client.close()
        self.assertTrue(client._kill_cursors_executor._stopped)

        # Reusing the closed client should restart the thread.
        client.admin.command('isMaster')
        self.assertFalse(client._kill_cursors_executor._stopped)

        # Again, closing the client should stop the thread.
        client.close()
        self.assertTrue(client._kill_cursors_executor._stopped)

    def test_uri_connect_option(self):
        # Ensure that topology is not opened if connect=False.
        client = rs_client(connect=False)
        self.assertFalse(client._topology._opened)

        # Ensure kill cursors thread has not been started.
        kc_thread = client._kill_cursors_executor._thread
        self.assertFalse(kc_thread and kc_thread.is_alive())

        # Using the client should open topology and start the thread.
        client.admin.command('isMaster')
        self.assertTrue(client._topology._opened)
        kc_thread = client._kill_cursors_executor._thread
        self.assertTrue(kc_thread and kc_thread.is_alive())

        # Tear down.
        client.close()

    def test_close_does_not_open_servers(self):
        client = rs_client(connect=False)
        topology = client._topology
        self.assertEqual(topology._servers, {})
        client.close()
        self.assertEqual(topology._servers, {})

    def test_close_closes_sockets(self):
        client = rs_client()
        self.addCleanup(client.close)
        client.test.test.find_one()
        topology = client._topology
        client.close()
        for server in topology._servers.values():
            self.assertFalse(server._pool.sockets)
            self.assertTrue(server._monitor._executor._stopped)
            self.assertTrue(server._monitor._rtt_monitor._executor._stopped)
            self.assertFalse(server._monitor._pool.sockets)
            self.assertFalse(server._monitor._rtt_monitor._pool.sockets)

    def test_bad_uri(self):
        with self.assertRaises(InvalidURI):
            MongoClient("http://localhost")

    @client_context.require_auth
    def test_auth_from_uri(self):
        host, port = client_context.host, client_context.port
        client_context.create_user("admin", "admin", "pass")
        self.addCleanup(client_context.drop_user, "admin", "admin")
        self.addCleanup(remove_all_users, self.client.pymongo_test)

        client_context.create_user(
            "pymongo_test", "user", "pass", roles=['userAdmin', 'readWrite'])

        with self.assertRaises(OperationFailure):
            connected(rs_or_single_client(
                "mongodb://a:b@%s:%d" % (host, port)))

        # No error.
        connected(rs_or_single_client_noauth(
            "mongodb://admin:pass@%s:%d" % (host, port)))

        # Wrong database.
        uri = "mongodb://admin:pass@%s:%d/pymongo_test" % (host, port)
        with self.assertRaises(OperationFailure):
            connected(rs_or_single_client(uri))

        # No error.
        connected(rs_or_single_client_noauth(
            "mongodb://user:pass@%s:%d/pymongo_test" % (host, port)))

        # Auth with lazy connection.
        rs_or_single_client_noauth(
            "mongodb://user:pass@%s:%d/pymongo_test" % (host, port),
            connect=False).pymongo_test.test.find_one()

        # Wrong password.
        bad_client = rs_or_single_client_noauth(
            "mongodb://user:wrong@%s:%d/pymongo_test" % (host, port),
            connect=False)

        self.assertRaises(OperationFailure,
                          bad_client.pymongo_test.test.find_one)

    @client_context.require_auth
    def test_username_and_password(self):
        client_context.create_user("admin", "ad min", "pa/ss")
        self.addCleanup(client_context.drop_user, "admin", "ad min")

        c = rs_or_single_client(username="ad min", password="pa/ss")

        # Username and password aren't in strings that will likely be logged.
        self.assertNotIn("ad min", repr(c))
        self.assertNotIn("ad min", str(c))
        self.assertNotIn("pa/ss", repr(c))
        self.assertNotIn("pa/ss", str(c))

        # Auth succeeds.
        c.server_info()

        with self.assertRaises(OperationFailure):
            rs_or_single_client(username="ad min", password="foo").server_info()

    @client_context.require_auth
    def test_lazy_auth_raises_operation_failure(self):
        lazy_client = rs_or_single_client_noauth(
            "mongodb://user:wrong@%s/pymongo_test" % (client_context.host,),
            connect=False)

        assertRaisesExactly(
            OperationFailure, lazy_client.test.collection.find_one)

    @client_context.require_no_tls
    def test_unix_socket(self):
        if not hasattr(socket, "AF_UNIX"):
            raise SkipTest("UNIX-sockets are not supported on this system")

        mongodb_socket = '/tmp/mongodb-%d.sock' % (client_context.port,)
        encoded_socket = (
            '%2Ftmp%2F' + 'mongodb-%d.sock' % (client_context.port,))
        if not os.access(mongodb_socket, os.R_OK):
            raise SkipTest("Socket file is not accessible")

        if client_context.auth_enabled:
            uri = "mongodb://%s:%s@%s" % (db_user, db_pwd, encoded_socket)
        else:
            uri = "mongodb://%s" % encoded_socket

        # Confirm we can do operations via the socket.
        client = rs_or_single_client(uri)
        client.pymongo_test.test.insert_one({"dummy": "object"})
        dbs = client.list_database_names()
        self.assertTrue("pymongo_test" in dbs)

        self.assertTrue(mongodb_socket in repr(client))

        # Confirm it fails with a missing socket.
        self.assertRaises(
            ConnectionFailure,
            connected, MongoClient("mongodb://%2Ftmp%2Fnon-existent.sock",
                                   serverSelectionTimeoutMS=100))

    def test_document_class(self):
        c = self.client
        db = c.pymongo_test
        db.test.insert_one({"x": 1})

        self.assertEqual(dict, c.codec_options.document_class)
        self.assertTrue(isinstance(db.test.find_one(), dict))
        self.assertFalse(isinstance(db.test.find_one(), SON))

        c = rs_or_single_client(document_class=SON)
        db = c.pymongo_test

        self.assertEqual(SON, c.codec_options.document_class)
        self.assertTrue(isinstance(db.test.find_one(), SON))

    def test_timeouts(self):
        client = rs_or_single_client(
            connectTimeoutMS=10500,
            socketTimeoutMS=10500,
            maxIdleTimeMS=10500,
            serverSelectionTimeoutMS=10500)
        self.assertEqual(10.5, get_pool(client).opts.connect_timeout)
        self.assertEqual(10.5, get_pool(client).opts.socket_timeout)
        self.assertEqual(10.5, get_pool(client).opts.max_idle_time_seconds)
        self.assertEqual(10500, client.max_idle_time_ms)
        self.assertEqual(10.5, client.server_selection_timeout)

    def test_socket_timeout_ms_validation(self):
        c = rs_or_single_client(socketTimeoutMS=10 * 1000)
        self.assertEqual(10, get_pool(c).opts.socket_timeout)

        c = connected(rs_or_single_client(socketTimeoutMS=None))
        self.assertEqual(None, get_pool(c).opts.socket_timeout)

        c = connected(rs_or_single_client(socketTimeoutMS=0))
        self.assertEqual(None, get_pool(c).opts.socket_timeout)

        self.assertRaises(ValueError,
                          rs_or_single_client, socketTimeoutMS=-1)

        self.assertRaises(ValueError,
                          rs_or_single_client, socketTimeoutMS=1e10)

        self.assertRaises(ValueError,
                          rs_or_single_client, socketTimeoutMS='foo')

    def test_socket_timeout(self):
        no_timeout = self.client
        timeout_sec = 1
        timeout = rs_or_single_client(socketTimeoutMS=1000 * timeout_sec)

        no_timeout.pymongo_test.drop_collection("test")
        no_timeout.pymongo_test.test.insert_one({"x": 1})

        # A $where clause that takes a second longer than the timeout
        where_func = delay(timeout_sec + 1)

        def get_x(db):
            doc = next(db.test.find().where(where_func))
            return doc["x"]
        self.assertEqual(1, get_x(no_timeout.pymongo_test))
        self.assertRaises(NetworkTimeout, get_x, timeout.pymongo_test)

    def test_server_selection_timeout(self):
        client = MongoClient(serverSelectionTimeoutMS=100, connect=False)
        self.assertAlmostEqual(0.1, client.server_selection_timeout)

        client = MongoClient(serverSelectionTimeoutMS=0, connect=False)
        self.assertAlmostEqual(0, client.server_selection_timeout)

        self.assertRaises(ValueError, MongoClient,
                          serverSelectionTimeoutMS="foo", connect=False)
        self.assertRaises(ValueError, MongoClient,
                          serverSelectionTimeoutMS=-1, connect=False)
        self.assertRaises(ConfigurationError, MongoClient,
                          serverSelectionTimeoutMS=None, connect=False)

        client = MongoClient(
            'mongodb://localhost/?serverSelectionTimeoutMS=100', connect=False)
        self.assertAlmostEqual(0.1, client.server_selection_timeout)

        client = MongoClient(
            'mongodb://localhost/?serverSelectionTimeoutMS=0', connect=False)
        self.assertAlmostEqual(0, client.server_selection_timeout)

        # Test invalid timeout in URI ignored and set to default.
        client = MongoClient(
            'mongodb://localhost/?serverSelectionTimeoutMS=-1', connect=False)
        self.assertAlmostEqual(30, client.server_selection_timeout)

        client = MongoClient(
            'mongodb://localhost/?serverSelectionTimeoutMS=', connect=False)
        self.assertAlmostEqual(30, client.server_selection_timeout)

    def test_waitQueueTimeoutMS(self):
        client = rs_or_single_client(waitQueueTimeoutMS=2000)
        self.assertEqual(get_pool(client).opts.wait_queue_timeout, 2)

    def test_socketKeepAlive(self):
        pool = get_pool(self.client)
        with pool.get_socket({}) as sock_info:
            keepalive = sock_info.sock.getsockopt(socket.SOL_SOCKET,
                                                  socket.SO_KEEPALIVE)
            self.assertTrue(keepalive)

    def test_tz_aware(self):
        self.assertRaises(ValueError, MongoClient, tz_aware='foo')

        aware = rs_or_single_client(tz_aware=True)
        naive = self.client
        aware.pymongo_test.drop_collection("test")

        now = datetime.datetime.utcnow()
        aware.pymongo_test.test.insert_one({"x": now})

        self.assertEqual(None, naive.pymongo_test.test.find_one()["x"].tzinfo)
        self.assertEqual(utc, aware.pymongo_test.test.find_one()["x"].tzinfo)
        self.assertEqual(
            aware.pymongo_test.test.find_one()["x"].replace(tzinfo=None),
            naive.pymongo_test.test.find_one()["x"])

    @client_context.require_ipv6
    def test_ipv6(self):
        if client_context.tls:
            if not HAVE_IPADDRESS:
                raise SkipTest("Need the ipaddress module to test with SSL")

        if client_context.auth_enabled:
            auth_str = "%s:%s@" % (db_user, db_pwd)
        else:
            auth_str = ""

        uri = "mongodb://%s[::1]:%d" % (auth_str, client_context.port)
        if client_context.is_rs:
            uri += '/?replicaSet=' + client_context.replica_set_name

        client = rs_or_single_client_noauth(uri)
        client.pymongo_test.test.insert_one({"dummy": "object"})
        client.pymongo_test_bernie.test.insert_one({"dummy": "object"})

        dbs = client.list_database_names()
        self.assertTrue("pymongo_test" in dbs)
        self.assertTrue("pymongo_test_bernie" in dbs)

    def test_contextlib(self):
        client = rs_or_single_client()
        client.pymongo_test.drop_collection("test")
        client.pymongo_test.test.insert_one({"foo": "bar"})

        # The socket used for the previous commands has been returned to the
        # pool
        self.assertEqual(1, len(get_pool(client).sockets))

        with contextlib.closing(client):
            self.assertEqual("bar", client.pymongo_test.test.find_one()["foo"])
            self.assertEqual(1, len(get_pool(client).sockets))
        self.assertEqual(0, len(get_pool(client).sockets))

        with client as client:
            self.assertEqual("bar", client.pymongo_test.test.find_one()["foo"])
        self.assertEqual(0, len(get_pool(client).sockets))

    def test_interrupt_signal(self):
        if sys.platform.startswith('java'):
            # We can't figure out how to raise an exception on a thread that's
            # blocked on a socket, whether that's the main thread or a worker,
            # without simply killing the whole thread in Jython. This suggests
            # PYTHON-294 can't actually occur in Jython.
            raise SkipTest("Can't test interrupts in Jython")
        if is_greenthread_patched():
            raise SkipTest("Can't reliably test interrupts with green threads")

        # Test fix for PYTHON-294 -- make sure MongoClient closes its
        # socket if it gets an interrupt while waiting to recv() from it.
        db = self.client.pymongo_test

        # A $where clause which takes 1.5 sec to execute
        where = delay(1.5)

        # Need exactly 1 document so find() will execute its $where clause once
        db.drop_collection('foo')
        db.foo.insert_one({'_id': 1})

        old_signal_handler = None
        try:
            # Platform-specific hacks for raising a KeyboardInterrupt on the
            # main thread while find() is in-progress: On Windows, SIGALRM is
            # unavailable so we use a second thread. In our Evergreen setup on
            # Linux, the thread technique causes an error in the test at
            # sock.recv(): TypeError: 'int' object is not callable
            # We don't know what causes this, so we hack around it.

            if sys.platform == 'win32':
                def interrupter():
                    # Raises KeyboardInterrupt in the main thread
                    time.sleep(0.25)
                    thread.interrupt_main()

                thread.start_new_thread(interrupter, ())
            else:
                # Convert SIGALRM to SIGINT -- it's hard to schedule a SIGINT
                # for one second in the future, but easy to schedule SIGALRM.
                def sigalarm(num, frame):
                    raise KeyboardInterrupt

                old_signal_handler = signal.signal(signal.SIGALRM, sigalarm)
                signal.alarm(1)

            raised = False
            try:
                # Will be interrupted by a KeyboardInterrupt.
                next(db.foo.find({'$where': where}))
            except KeyboardInterrupt:
                raised = True

            # Can't use self.assertRaises() because it doesn't catch system
            # exceptions
            self.assertTrue(raised, "Didn't raise expected KeyboardInterrupt")

            # Raises AssertionError due to PYTHON-294 -- Mongo's response to
            # the previous find() is still waiting to be read on the socket,
            # so the request id's don't match.
            self.assertEqual(
                {'_id': 1},
                next(db.foo.find())
            )
        finally:
            if old_signal_handler:
                signal.signal(signal.SIGALRM, old_signal_handler)

    def test_operation_failure(self):
        # Ensure MongoClient doesn't close socket after it gets an error
        # response to getLastError. PYTHON-395. We need a new client here
        # to avoid race conditions caused by replica set failover or idle
        # socket reaping.
        client = single_client()
        client.pymongo_test.test.find_one()
        pool = get_pool(client)
        socket_count = len(pool.sockets)
        self.assertGreaterEqual(socket_count, 1)
        old_sock_info = next(iter(pool.sockets))
        client.pymongo_test.test.drop()
        client.pymongo_test.test.insert_one({'_id': 'foo'})
        self.assertRaises(
            OperationFailure,
            client.pymongo_test.test.insert_one, {'_id': 'foo'})

        self.assertEqual(socket_count, len(pool.sockets))
        new_sock_info = next(iter(pool.sockets))
        self.assertEqual(old_sock_info, new_sock_info)

    def test_lazy_connect_w0(self):
        # Ensure that connect-on-demand works when the first operation is
        # an unacknowledged write. This exercises _writable_max_wire_version().

        # Use a separate collection to avoid races where we're still
        # completing an operation on a collection while the next test begins.
        client_context.client.drop_database('test_lazy_connect_w0')
        self.addCleanup(
            client_context.client.drop_database, 'test_lazy_connect_w0')

        client = rs_or_single_client(connect=False, w=0)
        client.test_lazy_connect_w0.test.insert_one({})
        wait_until(
            lambda: client.test_lazy_connect_w0.test.count_documents({}) == 1,
            "find one document")

        client = rs_or_single_client(connect=False, w=0)
        client.test_lazy_connect_w0.test.update_one({}, {'$set': {'x': 1}})
        wait_until(
            lambda: client.test_lazy_connect_w0.test.find_one().get('x') == 1,
            "update one document")

        client = rs_or_single_client(connect=False, w=0)
        client.test_lazy_connect_w0.test.delete_one({})
        wait_until(
            lambda: client.test_lazy_connect_w0.test.count_documents({}) == 0,
            "delete one document")

    @client_context.require_no_mongos
    def test_exhaust_network_error(self):
        # When doing an exhaust query, the socket stays checked out on success
        # but must be checked in on error to avoid semaphore leaks.
        client = rs_or_single_client(maxPoolSize=1, retryReads=False)
        collection = client.pymongo_test.test
        pool = get_pool(client)
        pool._check_interval_seconds = None  # Never check.

        # Ensure a socket.
        connected(client)

        # Cause a network error.
        sock_info = one(pool.sockets)
        sock_info.sock.close()
        cursor = collection.find(cursor_type=CursorType.EXHAUST)
        with self.assertRaises(ConnectionFailure):
            next(cursor)

        self.assertTrue(sock_info.closed)

        # The semaphore was decremented despite the error.
        self.assertEqual(0, pool.requests)

    @client_context.require_auth
    def test_auth_network_error(self):
        # Make sure there's no semaphore leak if we get a network error
        # when authenticating a new socket with cached credentials.

        # Get a client with one socket so we detect if it's leaked.
        c = connected(rs_or_single_client(maxPoolSize=1,
                                          waitQueueTimeoutMS=1,
                                          retryReads=False))

        # Cause a network error on the actual socket.
        pool = get_pool(c)
        socket_info = one(pool.sockets)
        socket_info.sock.close()

        # SocketInfo.check_auth logs in with the new credential, but gets a
        # socket.error. Should be reraised as AutoReconnect.
        self.assertRaises(AutoReconnect, c.test.collection.find_one)

        # No semaphore leak, the pool is allowed to make a new socket.
        c.test.collection.find_one()

    @client_context.require_no_replica_set
    def test_connect_to_standalone_using_replica_set_name(self):
        client = single_client(replicaSet='anything',
                               serverSelectionTimeoutMS=100)

        with self.assertRaises(AutoReconnect):
            client.test.test.find_one()

    @client_context.require_replica_set
    def test_stale_getmore(self):
        # A cursor is created, but its member goes down and is removed from
        # the topology before the getMore message is sent. Test that
        # MongoClient._run_operation_with_response handles the error.
        with self.assertRaises(AutoReconnect):
            client = rs_client(connect=False,
                               serverSelectionTimeoutMS=100)
            client._run_operation(
                operation=message._GetMore('pymongo_test', 'collection',
                                           101, 1234, client.codec_options,
                                           ReadPreference.PRIMARY,
                                           None, client, None, None, False),
                unpack_res=Cursor(
                    client.pymongo_test.collection)._unpack_response,
                address=('not-a-member', 27017))

    def test_heartbeat_frequency_ms(self):
        class HeartbeatStartedListener(ServerHeartbeatListener):
            def __init__(self):
                self.results = []

            def started(self, event):
                self.results.append(event)

            def succeeded(self, event):
                pass

            def failed(self, event):
                pass

        old_init = ServerHeartbeatStartedEvent.__init__
        heartbeat_times = []

        def init(self, *args):
            old_init(self, *args)
            heartbeat_times.append(time.time())

        try:
            ServerHeartbeatStartedEvent.__init__ = init
            listener = HeartbeatStartedListener()
            uri = "mongodb://%s:%d/?heartbeatFrequencyMS=500" % (
                client_context.host, client_context.port)
            client = single_client(uri, event_listeners=[listener])
            wait_until(lambda: len(listener.results) >= 2,
                       "record two ServerHeartbeatStartedEvents")

            # Default heartbeatFrequencyMS is 10 sec. Check the interval was
            # closer to 0.5 sec with heartbeatFrequencyMS configured.
            self.assertAlmostEqual(
                heartbeat_times[1] - heartbeat_times[0], 0.5, delta=2)

            client.close()
        finally:
            ServerHeartbeatStartedEvent.__init__ = old_init

    def test_small_heartbeat_frequency_ms(self):
        uri = "mongodb://example/?heartbeatFrequencyMS=499"
        with self.assertRaises(ConfigurationError) as context:
            MongoClient(uri)

        self.assertIn('heartbeatFrequencyMS', str(context.exception))

    def test_compression(self):
        def compression_settings(client):
            pool_options = client._MongoClient__options.pool_options
            return pool_options.compression_settings

        uri = "mongodb://localhost:27017/?compressors=zlib"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, ['zlib'])
        uri = "mongodb://localhost:27017/?compressors=zlib&zlibCompressionLevel=4"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, ['zlib'])
        self.assertEqual(opts.zlib_compression_level, 4)
        uri = "mongodb://localhost:27017/?compressors=zlib&zlibCompressionLevel=-1"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, ['zlib'])
        self.assertEqual(opts.zlib_compression_level, -1)
        uri = "mongodb://localhost:27017"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, [])
        self.assertEqual(opts.zlib_compression_level, -1)
        uri = "mongodb://localhost:27017/?compressors=foobar"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, [])
        self.assertEqual(opts.zlib_compression_level, -1)
        uri = "mongodb://localhost:27017/?compressors=foobar,zlib"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, ['zlib'])
        self.assertEqual(opts.zlib_compression_level, -1)

        # According to the connection string spec, unsupported values
        # just raise a warning and are ignored.
        uri = "mongodb://localhost:27017/?compressors=zlib&zlibCompressionLevel=10"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, ['zlib'])
        self.assertEqual(opts.zlib_compression_level, -1)
        uri = "mongodb://localhost:27017/?compressors=zlib&zlibCompressionLevel=-2"
        client = MongoClient(uri, connect=False)
        opts = compression_settings(client)
        self.assertEqual(opts.compressors, ['zlib'])
        self.assertEqual(opts.zlib_compression_level, -1)

        if not _HAVE_SNAPPY:
            uri = "mongodb://localhost:27017/?compressors=snappy"
            client = MongoClient(uri, connect=False)
            opts = compression_settings(client)
            self.assertEqual(opts.compressors, [])
        else:
            uri = "mongodb://localhost:27017/?compressors=snappy"
            client = MongoClient(uri, connect=False)
            opts = compression_settings(client)
            self.assertEqual(opts.compressors, ['snappy'])
            uri = "mongodb://localhost:27017/?compressors=snappy,zlib"
            client = MongoClient(uri, connect=False)
            opts = compression_settings(client)
            self.assertEqual(opts.compressors, ['snappy', 'zlib'])

        if not _HAVE_ZSTD:
            uri = "mongodb://localhost:27017/?compressors=zstd"
            client = MongoClient(uri, connect=False)
            opts = compression_settings(client)
            self.assertEqual(opts.compressors, [])
        else:
            uri = "mongodb://localhost:27017/?compressors=zstd"
            client = MongoClient(uri, connect=False)
            opts = compression_settings(client)
            self.assertEqual(opts.compressors, ['zstd'])
            uri = "mongodb://localhost:27017/?compressors=zstd,zlib"
            client = MongoClient(uri, connect=False)
            opts = compression_settings(client)
            self.assertEqual(opts.compressors, ['zstd', 'zlib'])

        options = client_context.default_client_options
        if "compressors" in options and "zlib" in options["compressors"]:
            for level in range(-1, 10):
                client = single_client(zlibcompressionlevel=level)
                # No error
                client.pymongo_test.test.find_one()

    def test_reset_during_update_pool(self):
        client = rs_or_single_client(minPoolSize=10)
        self.addCleanup(client.close)
        client.admin.command('ping')
        pool = get_pool(client)
        generation = pool.gen.get_overall()

        # Continuously reset the pool.
        class ResetPoolThread(threading.Thread):
            def __init__(self, pool):
                super(ResetPoolThread, self).__init__()
                self.running = True
                self.pool = pool

            def stop(self):
                self.running = False

            def run(self):
                while self.running:
                    exc = AutoReconnect('mock pool error')
                    ctx = _ErrorContext(
                        exc, 0, pool.gen.get_overall(), False, None)
                    client._topology.handle_error(pool.address, ctx)
                    time.sleep(0.001)

        t = ResetPoolThread(pool)
        t.start()

        # Ensure that update_pool completes without error even when the pool
        # is reset concurrently.
        try:
            while True:
                for _ in range(10):
                    client._topology.update_pool(
                        client._MongoClient__all_credentials)
                if generation != pool.gen.get_overall():
                    break
        finally:
            t.stop()
            t.join()
        client.admin.command('ping')

    def test_background_connections_do_not_hold_locks(self):
        min_pool_size = 10
        client = rs_or_single_client(
            serverSelectionTimeoutMS=3000, minPoolSize=min_pool_size,
            connect=False)
        self.addCleanup(client.close)

        # Create a single connection in the pool.
        client.admin.command('ping')

        # Cause new connections stall for a few seconds.
        pool = get_pool(client)
        original_connect = pool.connect

        def stall_connect(*args, **kwargs):
            time.sleep(2)
            return original_connect(*args, **kwargs)

        pool.connect = stall_connect
        # Un-patch Pool.connect to break the cyclic reference.
        self.addCleanup(delattr, pool, 'connect')

        # Wait for the background thread to start creating connections
        wait_until(lambda: len(pool.sockets) > 1, 'start creating connections')

        # Assert that application operations do not block.
        for _ in range(10):
            start = time.monotonic()
            client.admin.command('ping')
            total = time.monotonic() - start
            # Each ping command should not take more than 2 seconds
            self.assertLess(total, 2)

    @client_context.require_replica_set
    def test_direct_connection(self):
        # direct_connection=True should result in Single topology.
        client = rs_or_single_client(directConnection=True)
        client.admin.command('ping')
        self.assertEqual(len(client.nodes), 1)
        self.assertEqual(client._topology_settings.get_topology_type(),
                         TOPOLOGY_TYPE.Single)
        client.close()

        # direct_connection=False should result in RS topology.
        client = rs_or_single_client(directConnection=False)
        client.admin.command('ping')
        self.assertGreaterEqual(len(client.nodes), 1)
        self.assertIn(client._topology_settings.get_topology_type(),
                      [TOPOLOGY_TYPE.ReplicaSetNoPrimary,
                       TOPOLOGY_TYPE.ReplicaSetWithPrimary])
        client.close()

        # directConnection=True, should error with multiple hosts as a list.
        with self.assertRaises(ConfigurationError):
            MongoClient(['host1', 'host2'], directConnection=True)

    @unittest.skipIf(sys.platform.startswith('java'),
                     'Jython does not support gc.get_objects')
    def test_continuous_network_errors(self):
        def server_description_count():
            i = 0
            for obj in gc.get_objects():
                try:
                    if isinstance(obj, ServerDescription):
                        i += 1
                except ReferenceError:
                    pass
            return i
        gc.collect()
        with client_knobs(min_heartbeat_interval=0.003):
            client = MongoClient(
                'invalid:27017',
                heartbeatFrequencyMS=3,
                serverSelectionTimeoutMS=100)
            initial_count = server_description_count()
            self.addCleanup(client.close)
            with self.assertRaises(ServerSelectionTimeoutError):
                client.test.test.find_one()
            gc.collect()
            final_count = server_description_count()
            # If a bug like PYTHON-2433 is reintroduced then too many
            # ServerDescriptions will be kept alive and this test will fail:
            # AssertionError: 4 != 22 within 5 delta (18 difference)
            self.assertAlmostEqual(initial_count, final_count, delta=10)

    @client_context.require_failCommand_fail_point
    def test_network_error_message(self):
        client = single_client(retryReads=False)
        self.addCleanup(client.close)
        client.admin.command('ping')  # connect
        with self.fail_point({'mode': {'times': 1},
                              'data': {'closeConnection': True,
                                       'failCommands': ['find']}}):
            expected = '%s:%s: ' % client.address
            with self.assertRaisesRegex(AutoReconnect, expected):
                client.pymongo_test.test.find_one({})


class TestExhaustCursor(IntegrationTest):
    """Test that clients properly handle errors from exhaust cursors."""

    def setUp(self):
        super(TestExhaustCursor, self).setUp()
        if client_context.is_mongos:
            raise SkipTest("mongos doesn't support exhaust, SERVER-2627")

    def test_exhaust_query_server_error(self):
        # When doing an exhaust query, the socket stays checked out on success
        # but must be checked in on error to avoid semaphore leaks.
        client = connected(rs_or_single_client(maxPoolSize=1))

        collection = client.pymongo_test.test
        pool = get_pool(client)
        sock_info = one(pool.sockets)

        # This will cause OperationFailure in all mongo versions since
        # the value for $orderby must be a document.
        cursor = collection.find(
            SON([('$query', {}), ('$orderby', True)]),
            cursor_type=CursorType.EXHAUST)

        self.assertRaises(OperationFailure, cursor.next)
        self.assertFalse(sock_info.closed)

        # The socket was checked in and the semaphore was decremented.
        self.assertIn(sock_info, pool.sockets)
        self.assertEqual(0, pool.requests)

    def test_exhaust_getmore_server_error(self):
        # When doing a getmore on an exhaust cursor, the socket stays checked
        # out on success but it's checked in on error to avoid semaphore leaks.
        client = rs_or_single_client(maxPoolSize=1)
        collection = client.pymongo_test.test
        collection.drop()

        collection.insert_many([{} for _ in range(200)])
        self.addCleanup(client_context.client.pymongo_test.test.drop)

        pool = get_pool(client)
        pool._check_interval_seconds = None  # Never check.
        sock_info = one(pool.sockets)

        cursor = collection.find(cursor_type=CursorType.EXHAUST)

        # Initial query succeeds.
        cursor.next()

        # Cause a server error on getmore.
        def receive_message(request_id):
            # Discard the actual server response.
            SocketInfo.receive_message(sock_info, request_id)

            # responseFlags bit 1 is QueryFailure.
            msg = struct.pack('<iiiii', 1 << 1, 0, 0, 0, 0)
            msg += encode({'$err': 'mock err', 'code': 0})
            return message._OpReply.unpack(msg)

        sock_info.receive_message = receive_message
        self.assertRaises(OperationFailure, list, cursor)
        # Unpatch the instance.
        del sock_info.receive_message

        # The socket is returned to the pool and it still works.
        self.assertEqual(200, collection.count_documents({}))
        self.assertIn(sock_info, pool.sockets)

    def test_exhaust_query_network_error(self):
        # When doing an exhaust query, the socket stays checked out on success
        # but must be checked in on error to avoid semaphore leaks.
        client = connected(rs_or_single_client(maxPoolSize=1,
                                               retryReads=False))
        collection = client.pymongo_test.test
        pool = get_pool(client)
        pool._check_interval_seconds = None  # Never check.

        # Cause a network error.
        sock_info = one(pool.sockets)
        sock_info.sock.close()

        cursor = collection.find(cursor_type=CursorType.EXHAUST)
        self.assertRaises(ConnectionFailure, cursor.next)
        self.assertTrue(sock_info.closed)

        # The socket was closed and the semaphore was decremented.
        self.assertNotIn(sock_info, pool.sockets)
        self.assertEqual(0, pool.requests)

    def test_exhaust_getmore_network_error(self):
        # When doing a getmore on an exhaust cursor, the socket stays checked
        # out on success but it's checked in on error to avoid semaphore leaks.
        client = rs_or_single_client(maxPoolSize=1)
        collection = client.pymongo_test.test
        collection.drop()
        collection.insert_many([{} for _ in range(200)])  # More than one batch.
        pool = get_pool(client)
        pool._check_interval_seconds = None  # Never check.

        cursor = collection.find(cursor_type=CursorType.EXHAUST)

        # Initial query succeeds.
        cursor.next()

        # Cause a network error.
        sock_info = cursor._Cursor__sock_mgr.sock
        sock_info.sock.close()

        # A getmore fails.
        self.assertRaises(ConnectionFailure, list, cursor)
        self.assertTrue(sock_info.closed)

        # The socket was closed and the semaphore was decremented.
        self.assertNotIn(sock_info, pool.sockets)
        self.assertEqual(0, pool.requests)


class TestClientLazyConnect(IntegrationTest):
    """Test concurrent operations on a lazily-connecting MongoClient."""

    def _get_client(self):
        return rs_or_single_client(connect=False)

    def test_insert_one(self):
        def reset(collection):
            collection.drop()

        def insert_one(collection, _):
            collection.insert_one({})

        def test(collection):
            self.assertEqual(NTHREADS, collection.count_documents({}))

        lazy_client_trial(reset, insert_one, test, self._get_client)

    def test_update_one(self):
        def reset(collection):
            collection.drop()
            collection.insert_one({'i': 0})

        # Update doc 10 times.
        def update_one(collection, _):
            collection.update_one({}, {'$inc': {'i': 1}})

        def test(collection):
            self.assertEqual(NTHREADS, collection.find_one()['i'])

        lazy_client_trial(reset, update_one, test, self._get_client)

    def test_delete_one(self):
        def reset(collection):
            collection.drop()
            collection.insert_many([{'i': i} for i in range(NTHREADS)])

        def delete_one(collection, i):
            collection.delete_one({'i': i})

        def test(collection):
            self.assertEqual(0, collection.count_documents({}))

        lazy_client_trial(reset, delete_one, test, self._get_client)

    def test_find_one(self):
        results = []

        def reset(collection):
            collection.drop()
            collection.insert_one({})
            results[:] = []

        def find_one(collection, _):
            results.append(collection.find_one())

        def test(collection):
            self.assertEqual(NTHREADS, len(results))

        lazy_client_trial(reset, find_one, test, self._get_client)

    def test_max_bson_size(self):
        c = self._get_client()

        # max_bson_size will cause the client to connect.
        ismaster = c.db.command('ismaster')
        self.assertEqual(ismaster['maxBsonObjectSize'], c.max_bson_size)
        if 'maxMessageSizeBytes' in ismaster:
            self.assertEqual(
                ismaster['maxMessageSizeBytes'],
                c.max_message_size)


class TestMongoClientFailover(MockClientTest):

    def test_discover_primary(self):
        # Disable background refresh.
        with client_knobs(heartbeat_frequency=999999):
            c = MockClient(
                standalones=[],
                members=['a:1', 'b:2', 'c:3'],
                mongoses=[],
                host='b:2',  # Pass a secondary.
                replicaSet='rs')
            self.addCleanup(c.close)

            wait_until(lambda: len(c.nodes) == 3, 'connect')
            self.assertEqual(c.address, ('a', 1))

            # Fail over.
            c.kill_host('a:1')
            c.mock_primary = 'b:2'

            c.close()
            self.assertEqual(0, len(c.nodes))

            t = c._get_topology()
            t.select_servers(writable_server_selector)  # Reconnect.
            self.assertEqual(c.address, ('b', 2))

            # a:1 not longer in nodes.
            self.assertLess(len(c.nodes), 3)

            # c:3 is rediscovered.
            t.select_server_by_address(('c', 3))

    def test_reconnect(self):
        # Verify the node list isn't forgotten during a network failure.
        c = MockClient(
            standalones=[],
            members=['a:1', 'b:2', 'c:3'],
            mongoses=[],
            host='b:2',  # Pass a secondary.
            replicaSet='rs',
            retryReads=False,
            serverSelectionTimeoutMS=1000,
        )
        self.addCleanup(c.close)

        wait_until(lambda: len(c.nodes) == 3, 'connect')

        # Total failure.
        c.kill_host('a:1')
        c.kill_host('b:2')
        c.kill_host('c:3')

        # MongoClient discovers it's alone. The first attempt raises either
        # ServerSelectionTimeoutError or AutoReconnect (from
        # MockPool.get_socket).
        self.assertRaises(AutoReconnect, c.db.collection.find_one)

        # But it can reconnect.
        c.revive_host('a:1')
        c._get_topology().select_servers(writable_server_selector)
        self.assertEqual(c.address, ('a', 1))

    def _test_network_error(self, operation_callback):
        # Verify only the disconnected server is reset by a network failure.

        # Disable background refresh.
        with client_knobs(heartbeat_frequency=999999):
            c = MockClient(
                standalones=[],
                members=['a:1', 'b:2'],
                mongoses=[],
                host='a:1',
                replicaSet='rs',
                connect=False,
                retryReads=False,
                serverSelectionTimeoutMS=1000)
            self.addCleanup(c.close)

            # Set host-specific information so we can test whether it is reset.
            c.set_wire_version_range('a:1', 2, 6)
            c.set_wire_version_range('b:2', 2, 7)
            c._get_topology().select_servers(writable_server_selector)
            wait_until(lambda: len(c.nodes) == 2, 'connect')

            c.kill_host('a:1')

            # MongoClient is disconnected from the primary. This raises either
            # ServerSelectionTimeoutError or AutoReconnect (from
            # MockPool.get_socket).
            self.assertRaises(AutoReconnect, operation_callback, c)

            # The primary's description is reset.
            server_a = c._get_topology().get_server_by_address(('a', 1))
            sd_a = server_a.description
            self.assertEqual(SERVER_TYPE.Unknown, sd_a.server_type)
            self.assertEqual(0, sd_a.min_wire_version)
            self.assertEqual(0, sd_a.max_wire_version)

            # ...but not the secondary's.
            server_b = c._get_topology().get_server_by_address(('b', 2))
            sd_b = server_b.description
            self.assertEqual(SERVER_TYPE.RSSecondary, sd_b.server_type)
            self.assertEqual(2, sd_b.min_wire_version)
            self.assertEqual(7, sd_b.max_wire_version)

    def test_network_error_on_query(self):
        callback = lambda client: client.db.collection.find_one()
        self._test_network_error(callback)

    def test_network_error_on_insert(self):
        callback = lambda client: client.db.collection.insert_one({})
        self._test_network_error(callback)

    def test_network_error_on_update(self):
        callback = lambda client: client.db.collection.update_one(
            {}, {'$unset': 'x'})
        self._test_network_error(callback)

    def test_network_error_on_replace(self):
        callback = lambda client: client.db.collection.replace_one({}, {})
        self._test_network_error(callback)

    def test_network_error_on_delete(self):
        callback = lambda client: client.db.collection.delete_many({})
        self._test_network_error(callback)

    def test_gevent_task(self):
        if not gevent_monkey_patched():
            raise SkipTest("Must be running monkey patched by gevent")
        from gevent import spawn
        def poller():
            while True:
                client_context.client.pymongo_test.test.insert_one({})

        task = spawn(poller)
        task.kill()
        self.assertTrue(task.dead)

    def test_gevent_timeout(self):
        if not gevent_monkey_patched():
            raise SkipTest("Must be running monkey patched by gevent")
        from gevent import spawn, Timeout
        client = rs_or_single_client(maxPoolSize=1)
        coll = client.pymongo_test.test
        coll.insert_one({})

        def contentious_task():
            # The 10 second timeout causes this test to fail without blocking
            # forever if a bug like PYTHON-2334 is reintroduced.
            with Timeout(10):
                coll.find_one({'$where': delay(1)})

        def timeout_task():
            with Timeout(.5):
                try:
                    coll.find_one({})
                except Timeout:
                    pass

        ct = spawn(contentious_task)
        tt = spawn(timeout_task)
        tt.join(15)
        ct.join(15)
        self.assertTrue(tt.dead)
        self.assertTrue(ct.dead)
        self.assertIsNone(tt.get())
        self.assertIsNone(ct.get())

    def test_gevent_timeout_when_creating_connection(self):
        if not gevent_monkey_patched():
            raise SkipTest("Must be running monkey patched by gevent")
        from gevent import Timeout, spawn
        client = rs_or_single_client()
        self.addCleanup(client.close)
        coll = client.pymongo_test.test
        pool = get_pool(client)

        # Patch the pool to delay the connect method.
        def delayed_connect(*args, **kwargs):
            time.sleep(3)
            return pool.__class__.connect(pool, *args, **kwargs)

        pool.connect = delayed_connect

        def timeout_task():
            with Timeout(1):
                try:
                    coll.find_one({})
                    return False
                except Timeout:
                    return True

        tt = spawn(timeout_task)
        tt.join(10)

        # Assert that we got our active_sockets count back
        self.assertEqual(pool.active_sockets, 0)
        # Assert the greenlet is dead
        self.assertTrue(tt.dead)
        # Assert that the Timeout was raised all the way to the try
        self.assertTrue(tt.get())
        # Unpatch the instance.
        del pool.connect


class TestClientPool(MockClientTest):

    @client_context.require_connection
    def test_rs_client_does_not_maintain_pool_to_arbiters(self):
        listener = CMAPListener()
        c = MockClient(
            standalones=[],
            members=['a:1', 'b:2', 'c:3', 'd:4'],
            mongoses=[],
            arbiters=['c:3'],  # c:3 is an arbiter.
            down_hosts=['d:4'],  # d:4 is unreachable.
            host=['a:1', 'b:2', 'c:3', 'd:4'],
            replicaSet='rs',
            minPoolSize=1,  # minPoolSize
            event_listeners=[listener],
        )
        self.addCleanup(c.close)

        wait_until(lambda: len(c.nodes) == 3, 'connect')
        self.assertEqual(c.address, ('a', 1))
        self.assertEqual(c.arbiters, set([('c', 3)]))
        # Assert that we create 2 and only 2 pooled connections.
        listener.wait_for_event(monitoring.ConnectionReadyEvent, 2)
        self.assertEqual(
            listener.event_count(monitoring.ConnectionCreatedEvent), 2)
        # Assert that we do not create connections to arbiters.
        arbiter = c._topology.get_server_by_address(('c', 3))
        self.assertFalse(arbiter.pool.sockets)
        # Assert that we do not create connections to unknown servers.
        arbiter = c._topology.get_server_by_address(('d', 4))
        self.assertFalse(arbiter.pool.sockets)
        # Arbiter pool is not marked ready.
        self.assertEqual(
            listener.event_count(monitoring.PoolReadyEvent), 2)

    @client_context.require_connection
    def test_direct_client_maintains_pool_to_arbiter(self):
        listener = CMAPListener()
        c = MockClient(
            standalones=[],
            members=['a:1', 'b:2', 'c:3'],
            mongoses=[],
            arbiters=['c:3'],  # c:3 is an arbiter.
            host='c:3',
            directConnection=True,
            minPoolSize=1,  # minPoolSize
            event_listeners=[listener],
        )
        self.addCleanup(c.close)

        wait_until(lambda: len(c.nodes) == 1, 'connect')
        self.assertEqual(c.address, ('c', 3))
        # Assert that we create 1 pooled connection.
        listener.wait_for_event(monitoring.ConnectionReadyEvent, 1)
        self.assertEqual(
            listener.event_count(monitoring.ConnectionCreatedEvent), 1)
        arbiter = c._topology.get_server_by_address(('c', 3))
        self.assertEqual(len(arbiter.pool.sockets), 1)
        # Arbiter pool is marked ready.
        self.assertEqual(
            listener.event_count(monitoring.PoolReadyEvent), 1)


if __name__ == "__main__":
    unittest.main()
