# Copyright 2009-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.
"""Tools for connecting to MongoDB.
.. seealso:: :doc:`/examples/high_availability` for examples of connecting
to replica sets or sets of mongos servers.
To get a :class:`~pymongo.database.Database` instance from a
:class:`MongoClient` use either dictionary-style or attribute-style
access:
.. doctest::
>>> from pymongo import MongoClient
>>> c = MongoClient()
>>> c.test_database
Database(MongoClient(host=['localhost:27017'], document_class=dict, tz_aware=False, connect=True), 'test_database')
>>> c["test-database"]
Database(MongoClient(host=['localhost:27017'], document_class=dict, tz_aware=False, connect=True), 'test-database')
"""
from __future__ import annotations
import contextlib
import os
import weakref
from collections import defaultdict
from typing import (
TYPE_CHECKING,
Any,
Callable,
ContextManager,
FrozenSet,
Generic,
Iterator,
Mapping,
MutableMapping,
NoReturn,
Optional,
Sequence,
Type,
TypeVar,
Union,
cast,
)
from bson.codec_options import DEFAULT_CODEC_OPTIONS, CodecOptions, TypeRegistry
from bson.timestamp import Timestamp
from pymongo import (
_csot,
client_session,
common,
database,
helpers,
message,
periodic_executor,
uri_parser,
)
from pymongo.change_stream import ChangeStream, ClusterChangeStream
from pymongo.client_options import ClientOptions
from pymongo.client_session import _EmptyServerSession
from pymongo.command_cursor import CommandCursor
from pymongo.errors import (
AutoReconnect,
BulkWriteError,
ConfigurationError,
ConnectionFailure,
InvalidOperation,
NotPrimaryError,
OperationFailure,
PyMongoError,
ServerSelectionTimeoutError,
WaitQueueTimeoutError,
WriteConcernError,
)
from pymongo.lock import _HAS_REGISTER_AT_FORK, _create_lock, _release_locks
from pymongo.logger import _CLIENT_LOGGER, _log_or_warn
from pymongo.monitoring import ConnectionClosedReason
from pymongo.operations import _Op
from pymongo.read_preferences import ReadPreference, _ServerMode
from pymongo.server_selectors import writable_server_selector
from pymongo.server_type import SERVER_TYPE
from pymongo.settings import TopologySettings
from pymongo.topology import Topology, _ErrorContext
from pymongo.topology_description import TOPOLOGY_TYPE, TopologyDescription
from pymongo.typings import (
ClusterTime,
_Address,
_CollationIn,
_DocumentType,
_DocumentTypeArg,
_Pipeline,
)
from pymongo.uri_parser import (
_check_options,
_handle_option_deprecations,
_handle_security_options,
_normalize_options,
)
from pymongo.write_concern import DEFAULT_WRITE_CONCERN, WriteConcern
if TYPE_CHECKING:
import sys
from types import TracebackType
from bson.objectid import ObjectId
from pymongo.bulk import _Bulk
from pymongo.client_session import ClientSession, _ServerSession
from pymongo.cursor import _ConnectionManager
from pymongo.database import Database
from pymongo.message import _CursorAddress, _GetMore, _Query
from pymongo.pool import Connection
from pymongo.read_concern import ReadConcern
from pymongo.response import Response
from pymongo.server import Server
from pymongo.server_selectors import Selection
if sys.version_info[:2] >= (3, 9):
from collections.abc import Generator
else:
# Deprecated since version 3.9: collections.abc.Generator now supports [].
from typing import Generator
T = TypeVar("T")
_WriteCall = Callable[[Optional["ClientSession"], "Connection", bool], T]
_ReadCall = Callable[[Optional["ClientSession"], "Server", "Connection", _ServerMode], T]
class MongoClient(common.BaseObject, Generic[_DocumentType]):
"""
A client-side representation of a MongoDB cluster.
Instances can represent either a standalone MongoDB server, a replica
set, or a sharded cluster. Instances of this class are responsible for
maintaining up-to-date state of the cluster, and possibly cache
resources related to this, including background threads for monitoring,
and connection pools.
"""
HOST = "localhost"
PORT = 27017
# Define order to retrieve options from ClientOptions for __repr__.
# No host/port; these are retrieved from TopologySettings.
_constructor_args = ("document_class", "tz_aware", "connect")
_clients: weakref.WeakValueDictionary = weakref.WeakValueDictionary()
def __init__(
self,
host: Optional[Union[str, Sequence[str]]] = None,
port: Optional[int] = None,
document_class: Optional[Type[_DocumentType]] = None,
tz_aware: Optional[bool] = None,
connect: Optional[bool] = None,
type_registry: Optional[TypeRegistry] = None,
**kwargs: Any,
) -> None:
"""Client for a MongoDB instance, a replica set, or a set of mongoses.
.. warning:: Starting in PyMongo 4.0, ``directConnection`` now has a default value of
False instead of None.
For more details, see the relevant section of the PyMongo 4.x migration guide:
:ref:`pymongo4-migration-direct-connection`.
The client object is thread-safe and has connection-pooling built in.
If an operation fails because of a network error,
:class:`~pymongo.errors.ConnectionFailure` is raised and the client
reconnects in the background. Application code should handle this
exception (recognizing that the operation failed) and then continue to
execute.
The `host` parameter can be a full `mongodb URI
<http://dochub.mongodb.org/core/connections>`_, in addition to
a simple hostname. It can also be a list of hostnames but no more
than one URI. Any port specified in the host string(s) will override
the `port` parameter. For username and
passwords reserved characters like ':', '/', '+' and '@' must be
percent encoded following RFC 2396::
from urllib.parse import quote_plus
uri = "mongodb://%s:%s@%s" % (
quote_plus(user), quote_plus(password), host)
client = MongoClient(uri)
Unix domain sockets are also supported. The socket path must be percent
encoded in the URI::
uri = "mongodb://%s:%s@%s" % (
quote_plus(user), quote_plus(password), quote_plus(socket_path))
client = MongoClient(uri)
But not when passed as a simple hostname::
client = MongoClient('/tmp/mongodb-27017.sock')
Starting with version 3.6, PyMongo supports mongodb+srv:// URIs. The
URI must include one, and only one, hostname. The hostname will be
resolved to one or more DNS `SRV records
<https://en.wikipedia.org/wiki/SRV_record>`_ which will be used
as the seed list for connecting to the MongoDB deployment. When using
SRV URIs, the `authSource` and `replicaSet` configuration options can
be specified using `TXT records
<https://en.wikipedia.org/wiki/TXT_record>`_. See the
`Initial DNS Seedlist Discovery spec
<https://github.com/mongodb/specifications/blob/master/source/
initial-dns-seedlist-discovery/initial-dns-seedlist-discovery.rst>`_
for more details. Note that the use of SRV URIs implicitly enables
TLS support. Pass tls=false in the URI to override.
.. note:: MongoClient creation will block waiting for answers from
DNS when mongodb+srv:// URIs are used.
.. note:: Starting with version 3.0 the :class:`MongoClient`
constructor no longer blocks while connecting to the server or
servers, and it no longer raises
:class:`~pymongo.errors.ConnectionFailure` if they are
unavailable, nor :class:`~pymongo.errors.ConfigurationError`
if the user's credentials are wrong. Instead, the constructor
returns immediately and launches the connection process on
background threads. You can check if the server is available
like this::
from pymongo.errors import ConnectionFailure
client = MongoClient()
try:
# The ping command is cheap and does not require auth.
client.admin.command('ping')
except ConnectionFailure:
print("Server not available")
.. warning:: When using PyMongo in a multiprocessing context, please
read :ref:`multiprocessing` first.
.. note:: Many of the following options can be passed using a MongoDB
URI or keyword parameters. If the same option is passed in a URI and
as a keyword parameter the keyword parameter takes precedence.
:param host: hostname or IP address or Unix domain socket
path of a single mongod or mongos instance to connect to, or a
mongodb URI, or a list of hostnames (but no more than one mongodb
URI). If `host` is an IPv6 literal it must be enclosed in '['
and ']' characters
following the RFC2732 URL syntax (e.g. '[::1]' for localhost).
Multihomed and round robin DNS addresses are **not** supported.
:param port: port number on which to connect
:param document_class: default class to use for
documents returned from queries on this client
:param tz_aware: if ``True``,
:class:`~datetime.datetime` instances returned as values
in a document by this :class:`MongoClient` will be timezone
aware (otherwise they will be naive)
:param connect: if ``True`` (the default), immediately
begin connecting to MongoDB in the background. Otherwise connect
on the first operation.
:param type_registry: instance of
:class:`~bson.codec_options.TypeRegistry` to enable encoding
and decoding of custom types.
:param datetime_conversion: Specifies how UTC datetimes should be decoded
within BSON. Valid options include 'datetime_ms' to return as a
DatetimeMS, 'datetime' to return as a datetime.datetime and
raising a ValueError for out-of-range values, 'datetime_auto' to
return DatetimeMS objects when the underlying datetime is
out-of-range and 'datetime_clamp' to clamp to the minimum and
maximum possible datetimes. Defaults to 'datetime'. See
:ref:`handling-out-of-range-datetimes` for details.
| **Other optional parameters can be passed as keyword arguments:**
- `directConnection` (optional): if ``True``, forces this client to
connect directly to the specified MongoDB host as a standalone.
If ``false``, the client connects to the entire replica set of
which the given MongoDB host(s) is a part. If this is ``True``
and a mongodb+srv:// URI or a URI containing multiple seeds is
provided, an exception will be raised.
- `maxPoolSize` (optional): The maximum allowable number of
concurrent connections to each connected server. Requests to a
server will block if there are `maxPoolSize` outstanding
connections to the requested server. Defaults to 100. Can be
either 0 or None, in which case there is no limit on the number
of concurrent connections.
- `minPoolSize` (optional): The minimum required number of concurrent
connections that the pool will maintain to each connected server.
Default is 0.
- `maxIdleTimeMS` (optional): The maximum number of milliseconds that
a connection can remain idle in the pool before being removed and
replaced. Defaults to `None` (no limit).
- `maxConnecting` (optional): The maximum number of connections that
each pool can establish concurrently. Defaults to `2`.
- `timeoutMS`: (integer or None) Controls how long (in
milliseconds) the driver will wait when executing an operation
(including retry attempts) before raising a timeout error.
``0`` or ``None`` means no timeout.
- `socketTimeoutMS`: (integer or None) Controls how long (in
milliseconds) the driver will wait for a response after sending an
ordinary (non-monitoring) database operation before concluding that
a network error has occurred. ``0`` or ``None`` means no timeout.
Defaults to ``None`` (no timeout).
- `connectTimeoutMS`: (integer or None) Controls how long (in
milliseconds) the driver will wait during server monitoring when
connecting a new socket to a server before concluding the server
is unavailable. ``0`` or ``None`` means no timeout.
Defaults to ``20000`` (20 seconds).
- `server_selector`: (callable or None) Optional, user-provided
function that augments server selection rules. The function should
accept as an argument a list of
:class:`~pymongo.server_description.ServerDescription` objects and
return a list of server descriptions that should be considered
suitable for the desired operation.
- `serverSelectionTimeoutMS`: (integer) Controls how long (in
milliseconds) the driver will wait to find an available,
appropriate server to carry out a database operation; while it is
waiting, multiple server monitoring operations may be carried out,
each controlled by `connectTimeoutMS`. Defaults to ``30000`` (30
seconds).
- `waitQueueTimeoutMS`: (integer or None) How long (in milliseconds)
a thread will wait for a socket from the pool if the pool has no
free sockets. Defaults to ``None`` (no timeout).
- `heartbeatFrequencyMS`: (optional) The number of milliseconds
between periodic server checks, or None to accept the default
frequency of 10 seconds.
- `serverMonitoringMode`: (optional) The server monitoring mode to use.
Valid values are the strings: "auto", "stream", "poll". Defaults to "auto".
- `appname`: (string or None) The name of the application that
created this MongoClient instance. The server will log this value
upon establishing each connection. It is also recorded in the slow
query log and profile collections.
- `driver`: (pair or None) A driver implemented on top of PyMongo can
pass a :class:`~pymongo.driver_info.DriverInfo` to add its name,
version, and platform to the message printed in the server log when
establishing a connection.
- `event_listeners`: a list or tuple of event listeners. See
:mod:`~pymongo.monitoring` for details.
- `retryWrites`: (boolean) Whether supported write operations
executed within this MongoClient will be retried once after a
network error. Defaults to ``True``.
The supported write operations are:
- :meth:`~pymongo.collection.Collection.bulk_write`, as long as
:class:`~pymongo.operations.UpdateMany` or
:class:`~pymongo.operations.DeleteMany` are not included.
- :meth:`~pymongo.collection.Collection.delete_one`
- :meth:`~pymongo.collection.Collection.insert_one`
- :meth:`~pymongo.collection.Collection.insert_many`
- :meth:`~pymongo.collection.Collection.replace_one`
- :meth:`~pymongo.collection.Collection.update_one`
- :meth:`~pymongo.collection.Collection.find_one_and_delete`
- :meth:`~pymongo.collection.Collection.find_one_and_replace`
- :meth:`~pymongo.collection.Collection.find_one_and_update`
Unsupported write operations include, but are not limited to,
:meth:`~pymongo.collection.Collection.aggregate` using the ``$out``
pipeline operator and any operation with an unacknowledged write
concern (e.g. {w: 0})). See
https://github.com/mongodb/specifications/blob/master/source/retryable-writes/retryable-writes.rst
- `retryReads`: (boolean) Whether supported read operations
executed within this MongoClient will be retried once after a
network error. Defaults to ``True``.
The supported read operations are:
:meth:`~pymongo.collection.Collection.find`,
:meth:`~pymongo.collection.Collection.find_one`,
:meth:`~pymongo.collection.Collection.aggregate` without ``$out``,
:meth:`~pymongo.collection.Collection.distinct`,
:meth:`~pymongo.collection.Collection.count`,
:meth:`~pymongo.collection.Collection.estimated_document_count`,
:meth:`~pymongo.collection.Collection.count_documents`,
:meth:`pymongo.collection.Collection.watch`,
:meth:`~pymongo.collection.Collection.list_indexes`,
:meth:`pymongo.database.Database.watch`,
:meth:`~pymongo.database.Database.list_collections`,
:meth:`pymongo.mongo_client.MongoClient.watch`,
and :meth:`~pymongo.mongo_client.MongoClient.list_databases`.
Unsupported read operations include, but are not limited to
:meth:`~pymongo.database.Database.command` and any getMore
operation on a cursor.
Enabling retryable reads makes applications more resilient to
transient errors such as network failures, database upgrades, and
replica set failovers. For an exact definition of which errors
trigger a retry, see the `retryable reads specification
<https://github.com/mongodb/specifications/blob/master/source/retryable-reads/retryable-reads.rst>`_.
- `compressors`: Comma separated list of compressors for wire
protocol compression. The list is used to negotiate a compressor
with the server. Currently supported options are "snappy", "zlib"
and "zstd". Support for snappy requires the
`python-snappy <https://pypi.org/project/python-snappy/>`_ package.
zlib support requires the Python standard library zlib module. zstd
requires the `zstandard <https://pypi.org/project/zstandard/>`_
package. By default no compression is used. Compression support
must also be enabled on the server. MongoDB 3.6+ supports snappy
and zlib compression. MongoDB 4.2+ adds support for zstd.
See :ref:`network-compression-example` for details.
- `zlibCompressionLevel`: (int) The zlib compression level to use
when zlib is used as the wire protocol compressor. Supported values
are -1 through 9. -1 tells the zlib library to use its default
compression level (usually 6). 0 means no compression. 1 is best
speed. 9 is best compression. Defaults to -1.
- `uuidRepresentation`: The BSON representation to use when encoding
from and decoding to instances of :class:`~uuid.UUID`. Valid
values are the strings: "standard", "pythonLegacy", "javaLegacy",
"csharpLegacy", and "unspecified" (the default). New applications
should consider setting this to "standard" for cross language
compatibility. See :ref:`handling-uuid-data-example` for details.
- `unicode_decode_error_handler`: The error handler to apply when
a Unicode-related error occurs during BSON decoding that would
otherwise raise :exc:`UnicodeDecodeError`. Valid options include
'strict', 'replace', 'backslashreplace', 'surrogateescape', and
'ignore'. Defaults to 'strict'.
- `srvServiceName`: (string) The SRV service name to use for
"mongodb+srv://" URIs. Defaults to "mongodb". Use it like so::
MongoClient("mongodb+srv://example.com/?srvServiceName=customname")
- `srvMaxHosts`: (int) limits the number of mongos-like hosts a client will
connect to. More specifically, when a "mongodb+srv://" connection string
resolves to more than srvMaxHosts number of hosts, the client will randomly
choose an srvMaxHosts sized subset of hosts.
| **Write Concern options:**
| (Only set if passed. No default values.)
- `w`: (integer or string) If this is a replica set, write operations
will block until they have been replicated to the specified number
or tagged set of servers. `w=<int>` always includes the replica set
primary (e.g. w=3 means write to the primary and wait until
replicated to **two** secondaries). Passing w=0 **disables write
acknowledgement** and all other write concern options.
- `wTimeoutMS`: **DEPRECATED** (integer) Used in conjunction with `w`.
Specify a value in milliseconds to control how long to wait for write propagation
to complete. If replication does not complete in the given
timeframe, a timeout exception is raised. Passing wTimeoutMS=0
will cause **write operations to wait indefinitely**.
- `journal`: If ``True`` block until write operations have been
committed to the journal. Cannot be used in combination with
`fsync`. Write operations will fail with an exception if this
option is used when the server is running without journaling.
- `fsync`: If ``True`` and the server is running without journaling,
blocks until the server has synced all data files to disk. If the
server is running with journaling, this acts the same as the `j`
option, blocking until write operations have been committed to the
journal. Cannot be used in combination with `j`.
| **Replica set keyword arguments for connecting with a replica set
- either directly or via a mongos:**
- `replicaSet`: (string or None) The name of the replica set to
connect to. The driver will verify that all servers it connects to
match this name. Implies that the hosts specified are a seed list
and the driver should attempt to find all members of the set.
Defaults to ``None``.
| **Read Preference:**
- `readPreference`: The replica set read preference for this client.
One of ``primary``, ``primaryPreferred``, ``secondary``,
``secondaryPreferred``, or ``nearest``. Defaults to ``primary``.
- `readPreferenceTags`: Specifies a tag set as a comma-separated list
of colon-separated key-value pairs. For example ``dc:ny,rack:1``.
Defaults to ``None``.
- `maxStalenessSeconds`: (integer) The maximum estimated
length of time a replica set secondary can fall behind the primary
in replication before it will no longer be selected for operations.
Defaults to ``-1``, meaning no maximum. If maxStalenessSeconds
is set, it must be a positive integer greater than or equal to
90 seconds.
.. seealso:: :doc:`/examples/server_selection`
| **Authentication:**
- `username`: A string.
- `password`: A string.
Although username and password must be percent-escaped in a MongoDB
URI, they must not be percent-escaped when passed as parameters. In
this example, both the space and slash special characters are passed
as-is::
MongoClient(username="user name", password="pass/word")
- `authSource`: The database to authenticate on. Defaults to the
database specified in the URI, if provided, or to "admin".
- `authMechanism`: See :data:`~pymongo.auth.MECHANISMS` for options.
If no mechanism is specified, PyMongo automatically SCRAM-SHA-1
when connected to MongoDB 3.6 and negotiates the mechanism to use
(SCRAM-SHA-1 or SCRAM-SHA-256) when connected to MongoDB 4.0+.
- `authMechanismProperties`: Used to specify authentication mechanism
specific options. To specify the service name for GSSAPI
authentication pass authMechanismProperties='SERVICE_NAME:<service
name>'.
To specify the session token for MONGODB-AWS authentication pass
``authMechanismProperties='AWS_SESSION_TOKEN:<session token>'``.
.. seealso:: :doc:`/examples/authentication`
| **TLS/SSL configuration:**
- `tls`: (boolean) If ``True``, create the connection to the server
using transport layer security. Defaults to ``False``.
- `tlsInsecure`: (boolean) Specify whether TLS constraints should be
relaxed as much as possible. Setting ``tlsInsecure=True`` implies
``tlsAllowInvalidCertificates=True`` and
``tlsAllowInvalidHostnames=True``. Defaults to ``False``. Think
very carefully before setting this to ``True`` as it dramatically
reduces the security of TLS.
- `tlsAllowInvalidCertificates`: (boolean) If ``True``, continues
the TLS handshake regardless of the outcome of the certificate
verification process. If this is ``False``, and a value is not
provided for ``tlsCAFile``, PyMongo will attempt to load system
provided CA certificates. If the python version in use does not
support loading system CA certificates then the ``tlsCAFile``
parameter must point to a file of CA certificates.
``tlsAllowInvalidCertificates=False`` implies ``tls=True``.
Defaults to ``False``. Think very carefully before setting this
to ``True`` as that could make your application vulnerable to
on-path attackers.
- `tlsAllowInvalidHostnames`: (boolean) If ``True``, disables TLS
hostname verification. ``tlsAllowInvalidHostnames=False`` implies
``tls=True``. Defaults to ``False``. Think very carefully before
setting this to ``True`` as that could make your application
vulnerable to on-path attackers.
- `tlsCAFile`: A file containing a single or a bundle of
"certification authority" certificates, which are used to validate
certificates passed from the other end of the connection.
Implies ``tls=True``. Defaults to ``None``.
- `tlsCertificateKeyFile`: A file containing the client certificate
and private key. Implies ``tls=True``. Defaults to ``None``.
- `tlsCRLFile`: A file containing a PEM or DER formatted
certificate revocation list. Implies ``tls=True``. Defaults to
``None``.
- `tlsCertificateKeyFilePassword`: The password or passphrase for
decrypting the private key in ``tlsCertificateKeyFile``. Only
necessary if the private key is encrypted. Defaults to ``None``.
- `tlsDisableOCSPEndpointCheck`: (boolean) If ``True``, disables
certificate revocation status checking via the OCSP responder
specified on the server certificate.
``tlsDisableOCSPEndpointCheck=False`` implies ``tls=True``.
Defaults to ``False``.
- `ssl`: (boolean) Alias for ``tls``.
| **Read Concern options:**
| (If not set explicitly, this will use the server default)
- `readConcernLevel`: (string) The read concern level specifies the
level of isolation for read operations. For example, a read
operation using a read concern level of ``majority`` will only
return data that has been written to a majority of nodes. If the
level is left unspecified, the server default will be used.
| **Client side encryption options:**
| (If not set explicitly, client side encryption will not be enabled.)
- `auto_encryption_opts`: A
:class:`~pymongo.encryption_options.AutoEncryptionOpts` which
configures this client to automatically encrypt collection commands
and automatically decrypt results. See
:ref:`automatic-client-side-encryption` for an example.
If a :class:`MongoClient` is configured with
``auto_encryption_opts`` and a non-None ``maxPoolSize``, a
separate internal ``MongoClient`` is created if any of the
following are true:
- A ``key_vault_client`` is not passed to
:class:`~pymongo.encryption_options.AutoEncryptionOpts`
- ``bypass_auto_encrpytion=False`` is passed to
:class:`~pymongo.encryption_options.AutoEncryptionOpts`
| **Stable API options:**
| (If not set explicitly, Stable API will not be enabled.)
- `server_api`: A
:class:`~pymongo.server_api.ServerApi` which configures this
client to use Stable API. See :ref:`versioned-api-ref` for
details.
.. seealso:: The MongoDB documentation on `connections <https://dochub.mongodb.org/core/connections>`_.
.. versionchanged:: 4.5
Added the ``serverMonitoringMode`` keyword argument.
.. versionchanged:: 4.2
Added the ``timeoutMS`` keyword argument.
.. versionchanged:: 4.0
- Removed the fsync, unlock, is_locked, database_names, and
close_cursor methods.
See the :ref:`pymongo4-migration-guide`.
- Removed the ``waitQueueMultiple`` and ``socketKeepAlive``
keyword arguments.
- The default for `uuidRepresentation` was changed from
``pythonLegacy`` to ``unspecified``.
- Added the ``srvServiceName``, ``maxConnecting``, and ``srvMaxHosts`` URI and
keyword arguments.
.. versionchanged:: 3.12
Added the ``server_api`` keyword argument.
The following keyword arguments were deprecated:
- ``ssl_certfile`` and ``ssl_keyfile`` were deprecated in favor
of ``tlsCertificateKeyFile``.
.. versionchanged:: 3.11
Added the following keyword arguments and URI options:
- ``tlsDisableOCSPEndpointCheck``
- ``directConnection``
.. versionchanged:: 3.9
Added the ``retryReads`` keyword argument and URI option.
Added the ``tlsInsecure`` keyword argument and URI option.
The following keyword arguments and URI options were deprecated:
- ``wTimeout`` was deprecated in favor of ``wTimeoutMS``.
- ``j`` was deprecated in favor of ``journal``.
- ``ssl_cert_reqs`` was deprecated in favor of
``tlsAllowInvalidCertificates``.
- ``ssl_match_hostname`` was deprecated in favor of
``tlsAllowInvalidHostnames``.
- ``ssl_ca_certs`` was deprecated in favor of ``tlsCAFile``.
- ``ssl_certfile`` was deprecated in favor of
``tlsCertificateKeyFile``.
- ``ssl_crlfile`` was deprecated in favor of ``tlsCRLFile``.
- ``ssl_pem_passphrase`` was deprecated in favor of
``tlsCertificateKeyFilePassword``.
.. versionchanged:: 3.9
``retryWrites`` now defaults to ``True``.
.. versionchanged:: 3.8
Added the ``server_selector`` keyword argument.
Added the ``type_registry`` keyword argument.
.. versionchanged:: 3.7
Added the ``driver`` keyword argument.
.. versionchanged:: 3.6
Added support for mongodb+srv:// URIs.
Added the ``retryWrites`` keyword argument and URI option.
.. versionchanged:: 3.5
Add ``username`` and ``password`` options. Document the
``authSource``, ``authMechanism``, and ``authMechanismProperties``
options.
Deprecated the ``socketKeepAlive`` keyword argument and URI option.
``socketKeepAlive`` now defaults to ``True``.
.. versionchanged:: 3.0
:class:`~pymongo.mongo_client.MongoClient` is now the one and only
client class for a standalone server, mongos, or replica set.
It includes the functionality that had been split into
:class:`~pymongo.mongo_client.MongoReplicaSetClient`: it can connect
to a replica set, discover all its members, and monitor the set for
stepdowns, elections, and reconfigs.
The :class:`~pymongo.mongo_client.MongoClient` constructor no
longer blocks while connecting to the server or servers, and it no
longer raises :class:`~pymongo.errors.ConnectionFailure` if they
are unavailable, nor :class:`~pymongo.errors.ConfigurationError`
if the user's credentials are wrong. Instead, the constructor
returns immediately and launches the connection process on
background threads.
Therefore the ``alive`` method is removed since it no longer
provides meaningful information; even if the client is disconnected,
it may discover a server in time to fulfill the next operation.
In PyMongo 2.x, :class:`~pymongo.MongoClient` accepted a list of
standalone MongoDB servers and used the first it could connect to::
MongoClient(['host1.com:27017', 'host2.com:27017'])
A list of multiple standalones is no longer supported; if multiple
servers are listed they must be members of the same replica set, or
mongoses in the same sharded cluster.
The behavior for a list of mongoses is changed from "high
availability" to "load balancing". Before, the client connected to
the lowest-latency mongos in the list, and used it until a network
error prompted it to re-evaluate all mongoses' latencies and
reconnect to one of them. In PyMongo 3, the client monitors its
network latency to all the mongoses continuously, and distributes
operations evenly among those with the lowest latency. See
:ref:`mongos-load-balancing` for more information.
The ``connect`` option is added.
The ``start_request``, ``in_request``, and ``end_request`` methods
are removed, as well as the ``auto_start_request`` option.
The ``copy_database`` method is removed, see the
:doc:`copy_database examples </examples/copydb>` for alternatives.
The :meth:`MongoClient.disconnect` method is removed; it was a
synonym for :meth:`~pymongo.MongoClient.close`.
:class:`~pymongo.mongo_client.MongoClient` no longer returns an
instance of :class:`~pymongo.database.Database` for attribute names
with leading underscores. You must use dict-style lookups instead::
client['__my_database__']
Not::
client.__my_database__
.. versionchanged:: 4.7
Deprecated parameter ``wTimeoutMS``, use :meth:`~pymongo.timeout`.
"""
doc_class = document_class or dict
self.__init_kwargs: dict[str, Any] = {
"host": host,
"port": port,
"document_class": doc_class,
"tz_aware": tz_aware,
"connect": connect,
"type_registry": type_registry,
**kwargs,
}
if host is None:
host = self.HOST
if isinstance(host, str):
host = [host]
if port is None:
port = self.PORT
if not isinstance(port, int):
raise TypeError("port must be an instance of int")
# _pool_class, _monitor_class, and _condition_class are for deep
# customization of PyMongo, e.g. Motor.
pool_class = kwargs.pop("_pool_class", None)
monitor_class = kwargs.pop("_monitor_class", None)
condition_class = kwargs.pop("_condition_class", None)
# Parse options passed as kwargs.
keyword_opts = common._CaseInsensitiveDictionary(kwargs)
keyword_opts["document_class"] = doc_class
seeds = set()
username = None
password = None
dbase = None
opts = common._CaseInsensitiveDictionary()
fqdn = None
srv_service_name = keyword_opts.get("srvservicename")
srv_max_hosts = keyword_opts.get("srvmaxhosts")
if len([h for h in host if "/" in h]) > 1:
raise ConfigurationError("host must not contain multiple MongoDB URIs")
for entity in host:
# A hostname can only include a-z, 0-9, '-' and '.'. If we find a '/'
# it must be a URI,
# https://en.wikipedia.org/wiki/Hostname#Restrictions_on_valid_host_names
if "/" in entity:
# Determine connection timeout from kwargs.
timeout = keyword_opts.get("connecttimeoutms")
if timeout is not None:
timeout = common.validate_timeout_or_none_or_zero(
keyword_opts.cased_key("connecttimeoutms"), timeout
)
res = uri_parser.parse_uri(
entity,
port,
validate=True,
warn=True,
normalize=False,
connect_timeout=timeout,
srv_service_name=srv_service_name,
srv_max_hosts=srv_max_hosts,
)
seeds.update(res["nodelist"])
username = res["username"] or username
password = res["password"] or password
dbase = res["database"] or dbase
opts = res["options"]
fqdn = res["fqdn"]
else:
seeds.update(uri_parser.split_hosts(entity, port))
if not seeds:
raise ConfigurationError("need to specify at least one host")
for hostname in [node[0] for node in seeds]:
if _detect_external_db(hostname):
break
# Add options with named keyword arguments to the parsed kwarg options.
if type_registry is not None:
keyword_opts["type_registry"] = type_registry
if tz_aware is None:
tz_aware = opts.get("tz_aware", False)
if connect is None:
connect = opts.get("connect", True)
keyword_opts["tz_aware"] = tz_aware
keyword_opts["connect"] = connect
# Handle deprecated options in kwarg options.
keyword_opts = _handle_option_deprecations(keyword_opts)
# Validate kwarg options.
keyword_opts = common._CaseInsensitiveDictionary(
dict(common.validate(keyword_opts.cased_key(k), v) for k, v in keyword_opts.items())
)
# Override connection string options with kwarg options.
opts.update(keyword_opts)
if srv_service_name is None:
srv_service_name = opts.get("srvServiceName", common.SRV_SERVICE_NAME)
srv_max_hosts = srv_max_hosts or opts.get("srvmaxhosts")
# Handle security-option conflicts in combined options.
opts = _handle_security_options(opts)
# Normalize combined options.
opts = _normalize_options(opts)
_check_options(seeds, opts)
# Username and password passed as kwargs override user info in URI.
username = opts.get("username", username)
password = opts.get("password", password)
self.__options = options = ClientOptions(username, password, dbase, opts)
self.__default_database_name = dbase
self.__lock = _create_lock()
self.__kill_cursors_queue: list = []
self._event_listeners = options.pool_options._event_listeners
super().__init__(
options.codec_options,
options.read_preference,
options.write_concern,
options.read_concern,
)
self._topology_settings = TopologySettings(
seeds=seeds,
replica_set_name=options.replica_set_name,
pool_class=pool_class,
pool_options=options.pool_options,
monitor_class=monitor_class,
condition_class=condition_class,
local_threshold_ms=options.local_threshold_ms,
server_selection_timeout=options.server_selection_timeout,
server_selector=options.server_selector,
heartbeat_frequency=options.heartbeat_frequency,
fqdn=fqdn,
direct_connection=options.direct_connection,
load_balanced=options.load_balanced,
srv_service_name=srv_service_name,
srv_max_hosts=srv_max_hosts,
server_monitoring_mode=options.server_monitoring_mode,
)
self._opened = False
self._init_background()
if connect:
self._get_topology()
self._encrypter = None
if self.__options.auto_encryption_opts:
from pymongo.encryption import _Encrypter
self._encrypter = _Encrypter(self, self.__options.auto_encryption_opts)
self._timeout = self.__options.timeout
if _HAS_REGISTER_AT_FORK:
# Add this client to the list of weakly referenced items.
# This will be used later if we fork.
MongoClient._clients[self._topology._topology_id] = self
def _init_background(self, old_pid: Optional[int] = None) -> None:
self._topology = Topology(self._topology_settings)
# Seed the topology with the old one's pid so we can detect clients
# that are opened before a fork and used after.
self._topology._pid = old_pid
def target() -> bool:
client = self_ref()
if client is None:
return False # Stop the executor.
MongoClient._process_periodic_tasks(client)
return True
executor = periodic_executor.PeriodicExecutor(
interval=common.KILL_CURSOR_FREQUENCY,
min_interval=common.MIN_HEARTBEAT_INTERVAL,
target=target,
name="pymongo_kill_cursors_thread",
)
# We strongly reference the executor and it weakly references us via
# this closure. When the client is freed, stop the executor soon.
self_ref: Any = weakref.ref(self, executor.close)
self._kill_cursors_executor = executor
self._opened = False
def _after_fork(self) -> None:
"""Resets topology in a child after successfully forking."""
self._init_background(self._topology._pid)
# Reset the session pool to avoid duplicate sessions in the child process.
self._topology._session_pool.reset()
def _duplicate(self, **kwargs: Any) -> MongoClient:
args = self.__init_kwargs.copy()
args.update(kwargs)
return MongoClient(**args)
def _server_property(self, attr_name: str) -> Any:
"""An attribute of the current server's description.
If the client is not connected, this will block until a connection is
established or raise ServerSelectionTimeoutError if no server is
available.
Not threadsafe if used multiple times in a single method, since
the server may change. In such cases, store a local reference to a
ServerDescription first, then use its properties.
"""
server = self._get_topology().select_server(writable_server_selector, _Op.TEST)
return getattr(server.description, attr_name)
def watch(
self,
pipeline: Optional[_Pipeline] = None,
full_document: Optional[str] = None,
resume_after: Optional[Mapping[str, Any]] = None,
max_await_time_ms: Optional[int] = None,
batch_size: Optional[int] = None,
collation: Optional[_CollationIn] = None,
start_at_operation_time: Optional[Timestamp] = None,
session: Optional[client_session.ClientSession] = None,
start_after: Optional[Mapping[str, Any]] = None,
comment: Optional[Any] = None,
full_document_before_change: Optional[str] = None,
show_expanded_events: Optional[bool] = None,
) -> ChangeStream[_DocumentType]:
"""Watch changes on this cluster.
Performs an aggregation with an implicit initial ``$changeStream``
stage and returns a
:class:`~pymongo.change_stream.ClusterChangeStream` cursor which
iterates over changes on all databases on this cluster.
Introduced in MongoDB 4.0.
.. code-block:: python
with client.watch() as stream:
for change in stream:
print(change)
The :class:`~pymongo.change_stream.ClusterChangeStream` iterable
blocks until the next change document is returned or an error is
raised. If the
:meth:`~pymongo.change_stream.ClusterChangeStream.next` method
encounters a network error when retrieving a batch from the server,
it will automatically attempt to recreate the cursor such that no
change events are missed. Any error encountered during the resume
attempt indicates there may be an outage and will be raised.
.. code-block:: python
try:
with client.watch([{"$match": {"operationType": "insert"}}]) as stream:
for insert_change in stream:
print(insert_change)
except pymongo.errors.PyMongoError:
# The ChangeStream encountered an unrecoverable error or the
# resume attempt failed to recreate the cursor.
logging.error("...")
For a precise description of the resume process see the
`change streams specification`_.
:param pipeline: A list of aggregation pipeline stages to
append to an initial ``$changeStream`` stage. Not all
pipeline stages are valid after a ``$changeStream`` stage, see the
MongoDB documentation on change streams for the supported stages.
:param full_document: The fullDocument to pass as an option
to the ``$changeStream`` stage. Allowed values: 'updateLookup',
'whenAvailable', 'required'. When set to 'updateLookup', the
change notification for partial updates will include both a delta
describing the changes to the document, as well as a copy of the
entire document that was changed from some time after the change
occurred.
:param full_document_before_change: Allowed values: 'whenAvailable'
and 'required'. Change events may now result in a
'fullDocumentBeforeChange' response field.
:param resume_after: A resume token. If provided, the
change stream will start returning changes that occur directly
after the operation specified in the resume token. A resume token
is the _id value of a change document.
:param max_await_time_ms: The maximum time in milliseconds
for the server to wait for changes before responding to a getMore
operation.
:param batch_size: The maximum number of documents to return
per batch.
:param collation: The :class:`~pymongo.collation.Collation`
to use for the aggregation.
:param start_at_operation_time: If provided, the resulting
change stream will only return changes that occurred at or after
the specified :class:`~bson.timestamp.Timestamp`. Requires
MongoDB >= 4.0.
:param session: a
:class:`~pymongo.client_session.ClientSession`.
:param start_after: The same as `resume_after` except that
`start_after` can resume notifications after an invalidate event.
This option and `resume_after` are mutually exclusive.
:param comment: A user-provided comment to attach to this
command.
:param show_expanded_events: Include expanded events such as DDL events like `dropIndexes`.
:return: A :class:`~pymongo.change_stream.ClusterChangeStream` cursor.
.. versionchanged:: 4.3
Added `show_expanded_events` parameter.
.. versionchanged:: 4.2
Added ``full_document_before_change`` parameter.
.. versionchanged:: 4.1
Added ``comment`` parameter.
.. versionchanged:: 3.9
Added the ``start_after`` parameter.
.. versionadded:: 3.7
.. seealso:: The MongoDB documentation on `changeStreams <https://mongodb.com/docs/manual/changeStreams/>`_.
.. _change streams specification:
https://github.com/mongodb/specifications/blob/master/source/change-streams/change-streams.md
"""
return ClusterChangeStream(
self.admin,
pipeline,
full_document,
resume_after,
max_await_time_ms,
batch_size,
collation,
start_at_operation_time,
session,
start_after,
comment,
full_document_before_change,
show_expanded_events=show_expanded_events,
)
@property
def topology_description(self) -> TopologyDescription:
"""The description of the connected MongoDB deployment.
>>> client.topology_description
<TopologyDescription id: 605a7b04e76489833a7c6113, topology_type: ReplicaSetWithPrimary, servers: [<ServerDescription ('localhost', 27017) server_type: RSPrimary, rtt: 0.0007973677999995488>, <ServerDescription ('localhost', 27018) server_type: RSSecondary, rtt: 0.0005540556000003249>, <ServerDescription ('localhost', 27019) server_type: RSSecondary, rtt: 0.0010367483999999649>]>
>>> client.topology_description.topology_type_name
'ReplicaSetWithPrimary'
Note that the description is periodically updated in the background
but the returned object itself is immutable. Access this property again
to get a more recent
:class:`~pymongo.topology_description.TopologyDescription`.
:return: An instance of
:class:`~pymongo.topology_description.TopologyDescription`.
.. versionadded:: 4.0
"""
return self._topology.description
@property
def address(self) -> Optional[tuple[str, int]]:
"""(host, port) of the current standalone, primary, or mongos, or None.
Accessing :attr:`address` raises :exc:`~.errors.InvalidOperation` if
the client is load-balancing among mongoses, since there is no single
address. Use :attr:`nodes` instead.
If the client is not connected, this will block until a connection is
established or raise ServerSelectionTimeoutError if no server is
available.
.. versionadded:: 3.0
"""
topology_type = self._topology._description.topology_type
if (
topology_type == TOPOLOGY_TYPE.Sharded
and len(self.topology_description.server_descriptions()) > 1
):
raise InvalidOperation(
'Cannot use "address" property when load balancing among'
' mongoses, use "nodes" instead.'
)
if topology_type not in (
TOPOLOGY_TYPE.ReplicaSetWithPrimary,
TOPOLOGY_TYPE.Single,
TOPOLOGY_TYPE.LoadBalanced,
TOPOLOGY_TYPE.Sharded,
):
return None
return self._server_property("address")
@property
def primary(self) -> Optional[tuple[str, int]]:
"""The (host, port) of the current primary of the replica set.
Returns ``None`` if this client is not connected to a replica set,
there is no primary, or this client was created without the
`replicaSet` option.
.. versionadded:: 3.0
MongoClient gained this property in version 3.0.
"""
return self._topology.get_primary() # type: ignore[return-value]
@property
def secondaries(self) -> set[_Address]:
"""The secondary members known to this client.
A sequence of (host, port) pairs. Empty if this client is not
connected to a replica set, there are no visible secondaries, or this
client was created without the `replicaSet` option.
.. versionadded:: 3.0
MongoClient gained this property in version 3.0.
"""
return self._topology.get_secondaries()
@property
def arbiters(self) -> set[_Address]:
"""Arbiters in the replica set.
A sequence of (host, port) pairs. Empty if this client is not
connected to a replica set, there are no arbiters, or this client was
created without the `replicaSet` option.
"""
return self._topology.get_arbiters()
@property
def is_primary(self) -> bool:
"""If this client is connected to a server that can accept writes.
True if the current server is a standalone, mongos, or the primary of
a replica set. If the client is not connected, this will block until a
connection is established or raise ServerSelectionTimeoutError if no
server is available.
"""
return self._server_property("is_writable")
@property
def is_mongos(self) -> bool:
"""If this client is connected to mongos. If the client is not
connected, this will block until a connection is established or raise
ServerSelectionTimeoutError if no server is available.
"""
return self._server_property("server_type") == SERVER_TYPE.Mongos
@property
def nodes(self) -> FrozenSet[_Address]:
"""Set of all currently connected servers.
.. warning:: When connected to a replica set the value of :attr:`nodes`
can change over time as :class:`MongoClient`'s view of the replica
set changes. :attr:`nodes` can also be an empty set when
:class:`MongoClient` is first instantiated and hasn't yet connected
to any servers, or a network partition causes it to lose connection
to all servers.
"""
description = self._topology.description
return frozenset(s.address for s in description.known_servers)
@property
def options(self) -> ClientOptions:
"""The configuration options for this client.
:return: An instance of :class:`~pymongo.client_options.ClientOptions`.
.. versionadded:: 4.0
"""
return self.__options
def _end_sessions(self, session_ids: list[_ServerSession]) -> None:
"""Send endSessions command(s) with the given session ids."""
try:
# Use Connection.command directly to avoid implicitly creating
# another session.
with self._conn_for_reads(
ReadPreference.PRIMARY_PREFERRED, None, operation=_Op.END_SESSIONS
) as (
conn,
read_pref,
):
if not conn.supports_sessions:
return
for i in range(0, len(session_ids), common._MAX_END_SESSIONS):
spec = {"endSessions": session_ids[i : i + common._MAX_END_SESSIONS]}
conn.command("admin", spec, read_preference=read_pref, client=self)
except PyMongoError:
# Drivers MUST ignore any errors returned by the endSessions
# command.
pass
def close(self) -> None:
"""Cleanup client resources and disconnect from MongoDB.
End all server sessions created by this client by sending one or more
endSessions commands.
Close all sockets in the connection pools and stop the monitor threads.
.. versionchanged:: 4.0
Once closed, the client cannot be used again and any attempt will
raise :exc:`~pymongo.errors.InvalidOperation`.
.. versionchanged:: 3.6
End all server sessions created by this client.
"""
session_ids = self._topology.pop_all_sessions()
if session_ids:
self._end_sessions(session_ids)
# Stop the periodic task thread and then send pending killCursor
# requests before closing the topology.
self._kill_cursors_executor.close()
self._process_kill_cursors()
self._topology.close()
if self._encrypter:
# TODO: PYTHON-1921 Encrypted MongoClients cannot be re-opened.
self._encrypter.close()
def _get_topology(self) -> Topology:
"""Get the internal :class:`~pymongo.topology.Topology` object.
If this client was created with "connect=False", calling _get_topology
launches the connection process in the background.
"""
if not self._opened:
self._topology.open()
with self.__lock:
self._kill_cursors_executor.open()
self._opened = True
return self._topology
@contextlib.contextmanager
def _checkout(self, server: Server, session: Optional[ClientSession]) -> Iterator[Connection]:
in_txn = session and session.in_transaction
with _MongoClientErrorHandler(self, server, session) as err_handler:
# Reuse the pinned connection, if it exists.
if in_txn and session and session._pinned_connection:
err_handler.contribute_socket(session._pinned_connection)
yield session._pinned_connection
return
with server.checkout(handler=err_handler) as conn:
# Pin this session to the selected server or connection.
if (
in_txn
and session
and server.description.server_type
in (
SERVER_TYPE.Mongos,
SERVER_TYPE.LoadBalancer,
)
):
session._pin(server, conn)
err_handler.contribute_socket(conn)
if (
self._encrypter
and not self._encrypter._bypass_auto_encryption
and conn.max_wire_version < 8
):
raise ConfigurationError(
"Auto-encryption requires a minimum MongoDB version of 4.2"
)
yield conn
def _select_server(
self,
server_selector: Callable[[Selection], Selection],
session: Optional[ClientSession],
operation: str,
address: Optional[_Address] = None,
deprioritized_servers: Optional[list[Server]] = None,
operation_id: Optional[int] = None,
) -> Server:
"""Select a server to run an operation on this client.
:param server_selector: The server selector to use if the session is
not pinned and no address is given.
:param session: The ClientSession for the next operation, or None. May
be pinned to a mongos server address.
:param operation: The name of the operation that the server is being selected for.
:param address: Address when sending a message
to a specific server, used for getMore.
"""
try:
topology = self._get_topology()
if session and not session.in_transaction:
session._transaction.reset()
if not address and session:
address = session._pinned_address
if address:
# We're running a getMore or this session is pinned to a mongos.
server = topology.select_server_by_address(
address, operation, operation_id=operation_id
)
if not server:
raise AutoReconnect("server %s:%s no longer available" % address) # noqa: UP031
else:
server = topology.select_server(
server_selector,
operation,
deprioritized_servers=deprioritized_servers,
operation_id=operation_id,
)
return server
except PyMongoError as exc:
# Server selection errors in a transaction are transient.
if session and session.in_transaction:
exc._add_error_label("TransientTransactionError")
session._unpin()
raise
def _conn_for_writes(
self, session: Optional[ClientSession], operation: str
) -> ContextManager[Connection]:
server = self._select_server(writable_server_selector, session, operation)
return self._checkout(server, session)
@contextlib.contextmanager
def _conn_from_server(
self, read_preference: _ServerMode, server: Server, session: Optional[ClientSession]
) -> Iterator[tuple[Connection, _ServerMode]]:
assert read_preference is not None, "read_preference must not be None"
# Get a connection for a server matching the read preference, and yield
# conn with the effective read preference. The Server Selection
# Spec says not to send any $readPreference to standalones and to
# always send primaryPreferred when directly connected to a repl set
# member.
# Thread safe: if the type is single it cannot change.
# NOTE: We already opened the Topology when selecting a server so there's no need
# to call _get_topology() again.
single = self._topology.description.topology_type == TOPOLOGY_TYPE.Single
with self._checkout(server, session) as conn:
if single:
if conn.is_repl and not (session and session.in_transaction):
# Use primary preferred to ensure any repl set member
# can handle the request.
read_preference = ReadPreference.PRIMARY_PREFERRED
elif conn.is_standalone:
# Don't send read preference to standalones.
read_preference = ReadPreference.PRIMARY
yield conn, read_preference
def _conn_for_reads(
self,
read_preference: _ServerMode,
session: Optional[ClientSession],
operation: str,
) -> ContextManager[tuple[Connection, _ServerMode]]:
assert read_preference is not None, "read_preference must not be None"
server = self._select_server(read_preference, session, operation)
return self._conn_from_server(read_preference, server, session)
def _should_pin_cursor(self, session: Optional[ClientSession]) -> Optional[bool]:
return self.__options.load_balanced and not (session and session.in_transaction)
@_csot.apply
def _run_operation(
self,
operation: Union[_Query, _GetMore],
unpack_res: Callable,
address: Optional[_Address] = None,
) -> Response:
"""Run a _Query/_GetMore operation and return a Response.
:param operation: a _Query or _GetMore object.
:param unpack_res: A callable that decodes the wire protocol response.
:param address: Optional address when sending a message
to a specific server, used for getMore.
"""
if operation.conn_mgr:
server = self._select_server(
operation.read_preference,
operation.session,
operation.name,
address=address,
)
with operation.conn_mgr.lock:
with _MongoClientErrorHandler(self, server, operation.session) as err_handler:
err_handler.contribute_socket(operation.conn_mgr.conn)
return server.run_operation(
operation.conn_mgr.conn,
operation,
operation.read_preference,
self._event_listeners,
unpack_res,
self,
)
def _cmd(
_session: Optional[ClientSession],
server: Server,
conn: Connection,
read_preference: _ServerMode,
) -> Response:
operation.reset() # Reset op in case of retry.
return server.run_operation(
conn,
operation,
read_preference,
self._event_listeners,
unpack_res,
self,
)
return self._retryable_read(
_cmd,
operation.read_preference,
operation.session,
address=address,
retryable=isinstance(operation, message._Query),
operation=operation.name,
)
def _retry_with_session(
self,
retryable: bool,
func: _WriteCall[T],
session: Optional[ClientSession],
bulk: Optional[_Bulk],
operation: str,
operation_id: Optional[int] = None,
) -> T:
"""Execute an operation with at most one consecutive retries
Returns func()'s return value on success. On error retries the same
command.
Re-raises any exception thrown by func().
"""
# Ensure that the options supports retry_writes and there is a valid session not in
# transaction, otherwise, we will not support retry behavior for this txn.
retryable = bool(
retryable and self.options.retry_writes and session and not session.in_transaction
)
return self._retry_internal(
func=func,
session=session,
bulk=bulk,
operation=operation,
retryable=retryable,
operation_id=operation_id,
)
@_csot.apply
def _retry_internal(
self,
func: _WriteCall[T] | _ReadCall[T],
session: Optional[ClientSession],
bulk: Optional[_Bulk],
operation: str,
is_read: bool = False,
address: Optional[_Address] = None,
read_pref: Optional[_ServerMode] = None,
retryable: bool = False,
operation_id: Optional[int] = None,
) -> T:
"""Internal retryable helper for all client transactions.
:param func: Callback function we want to retry
:param session: Client Session on which the transaction should occur
:param bulk: Abstraction to handle bulk write operations
:param operation: The name of the operation that the server is being selected for
:param is_read: If this is an exclusive read transaction, defaults to False
:param address: Server Address, defaults to None
:param read_pref: Topology of read operation, defaults to None
:param retryable: If the operation should be retried once, defaults to None
:return: Output of the calling func()
"""
return _ClientConnectionRetryable(
mongo_client=self,
func=func,
bulk=bulk,
operation=operation,
is_read=is_read,
session=session,
read_pref=read_pref,
address=address,
retryable=retryable,
operation_id=operation_id,
).run()
def _retryable_read(
self,
func: _ReadCall[T],
read_pref: _ServerMode,
session: Optional[ClientSession],
operation: str,
address: Optional[_Address] = None,
retryable: bool = True,
operation_id: Optional[int] = None,
) -> T:
"""Execute an operation with consecutive retries if possible
Returns func()'s return value on success. On error retries the same
command.
Re-raises any exception thrown by func().
:param func: Read call we want to execute
:param read_pref: Desired topology of read operation
:param session: Client session we should use to execute operation
:param operation: The name of the operation that the server is being selected for
:param address: Optional address when sending a message, defaults to None
:param retryable: if we should attempt retries
(may not always be supported even if supplied), defaults to False
"""
# Ensure that the client supports retrying on reads and there is no session in
# transaction, otherwise, we will not support retry behavior for this call.
retryable = bool(
retryable and self.options.retry_reads and not (session and session.in_transaction)
)
return self._retry_internal(
func,
session,
None,
operation,
is_read=True,
address=address,
read_pref=read_pref,
retryable=retryable,
operation_id=operation_id,
)
def _retryable_write(
self,
retryable: bool,
func: _WriteCall[T],
session: Optional[ClientSession],
operation: str,
bulk: Optional[_Bulk] = None,
operation_id: Optional[int] = None,
) -> T:
"""Execute an operation with consecutive retries if possible
Returns func()'s return value on success. On error retries the same
command.
Re-raises any exception thrown by func().
:param retryable: if we should attempt retries (may not always be supported)
:param func: write call we want to execute during a session
:param session: Client session we will use to execute write operation
:param operation: The name of the operation that the server is being selected for
:param bulk: bulk abstraction to execute operations in bulk, defaults to None
"""
with self._tmp_session(session) as s:
return self._retry_with_session(retryable, func, s, bulk, operation, operation_id)
def __eq__(self, other: Any) -> bool:
if isinstance(other, self.__class__):
return self._topology == other._topology
return NotImplemented
def __ne__(self, other: Any) -> bool:
return not self == other
def __hash__(self) -> int:
return hash(self._topology)
def _repr_helper(self) -> str:
def option_repr(option: str, value: Any) -> str:
"""Fix options whose __repr__ isn't usable in a constructor."""
if option == "document_class":
if value is dict:
return "document_class=dict"
else:
return f"document_class={value.__module__}.{value.__name__}"
if option in common.TIMEOUT_OPTIONS and value is not None:
return f"{option}={int(value * 1000)}"
return f"{option}={value!r}"
# Host first...
options = [
"host=%r"
% [
"%s:%d" % (host, port) if port is not None else host
for host, port in self._topology_settings.seeds
]
]
# ... then everything in self._constructor_args...
options.extend(
option_repr(key, self.__options._options[key]) for key in self._constructor_args
)
# ... then everything else.
options.extend(
option_repr(key, self.__options._options[key])
for key in self.__options._options
if key not in set(self._constructor_args) and key != "username" and key != "password"
)
return ", ".join(options)
def __repr__(self) -> str:
return f"MongoClient({self._repr_helper()})"
def __getattr__(self, name: str) -> database.Database[_DocumentType]:
"""Get a database by name.
Raises :class:`~pymongo.errors.InvalidName` if an invalid
database name is used.
:param name: the name of the database to get
"""
if name.startswith("_"):
raise AttributeError(
f"MongoClient has no attribute {name!r}. To access the {name}"
f" database, use client[{name!r}]."
)
return self.__getitem__(name)
def __getitem__(self, name: str) -> database.Database[_DocumentType]:
"""Get a database by name.
Raises :class:`~pymongo.errors.InvalidName` if an invalid
database name is used.
:param name: the name of the database to get
"""
return database.Database(self, name)
def _cleanup_cursor(
self,
locks_allowed: bool,
cursor_id: int,
address: Optional[_CursorAddress],
conn_mgr: _ConnectionManager,
session: Optional[ClientSession],
explicit_session: bool,
) -> None:
"""Cleanup a cursor from cursor.close() or __del__.
This method handles cleanup for Cursors/CommandCursors including any
pinned connection or implicit session attached at the time the cursor
was closed or garbage collected.
:param locks_allowed: True if we are allowed to acquire locks.
:param cursor_id: The cursor id which may be 0.
:param address: The _CursorAddress.
:param conn_mgr: The _ConnectionManager for the pinned connection or None.
:param session: The cursor's session.
:param explicit_session: True if the session was passed explicitly.
"""
if locks_allowed:
if cursor_id:
if conn_mgr and conn_mgr.more_to_come:
# If this is an exhaust cursor and we haven't completely
# exhausted the result set we *must* close the socket
# to stop the server from sending more data.
assert conn_mgr.conn is not None
conn_mgr.conn.close_conn(ConnectionClosedReason.ERROR)
else:
self._close_cursor_now(cursor_id, address, session=session, conn_mgr=conn_mgr)
if conn_mgr:
conn_mgr.close()
else:
# The cursor will be closed later in a different session.
if cursor_id or conn_mgr:
self._close_cursor_soon(cursor_id, address, conn_mgr)
if session and not explicit_session:
session.end_session()
def _close_cursor_soon(
self,
cursor_id: int,
address: Optional[_CursorAddress],
conn_mgr: Optional[_ConnectionManager] = None,
) -> None:
"""Request that a cursor and/or connection be cleaned up soon."""
self.__kill_cursors_queue.append((address, cursor_id, conn_mgr))
def _close_cursor_now(
self,
cursor_id: int,
address: Optional[_CursorAddress],
session: Optional[ClientSession] = None,
conn_mgr: Optional[_ConnectionManager] = None,
) -> None:
"""Send a kill cursors message with the given id.
The cursor is closed synchronously on the current thread.
"""
if not isinstance(cursor_id, int):
raise TypeError("cursor_id must be an instance of int")
try:
if conn_mgr:
with conn_mgr.lock:
# Cursor is pinned to LB outside of a transaction.
assert address is not None
assert conn_mgr.conn is not None
self._kill_cursor_impl([cursor_id], address, session, conn_mgr.conn)
else:
self._kill_cursors([cursor_id], address, self._get_topology(), session)
except PyMongoError:
# Make another attempt to kill the cursor later.
self._close_cursor_soon(cursor_id, address)
def _kill_cursors(
self,
cursor_ids: Sequence[int],
address: Optional[_CursorAddress],
topology: Topology,
session: Optional[ClientSession],
) -> None:
"""Send a kill cursors message with the given ids."""
if address:
# address could be a tuple or _CursorAddress, but
# select_server_by_address needs (host, port).
server = topology.select_server_by_address(tuple(address), _Op.KILL_CURSORS) # type: ignore[arg-type]
else:
# Application called close_cursor() with no address.
server = topology.select_server(writable_server_selector, _Op.KILL_CURSORS)
with self._checkout(server, session) as conn:
assert address is not None
self._kill_cursor_impl(cursor_ids, address, session, conn)
def _kill_cursor_impl(
self,
cursor_ids: Sequence[int],
address: _CursorAddress,
session: Optional[ClientSession],
conn: Connection,
) -> None:
namespace = address.namespace
db, coll = namespace.split(".", 1)
spec = {"killCursors": coll, "cursors": cursor_ids}
conn.command(db, spec, session=session, client=self)
def _process_kill_cursors(self) -> None:
"""Process any pending kill cursors requests."""
address_to_cursor_ids = defaultdict(list)
pinned_cursors = []
# Other threads or the GC may append to the queue concurrently.
while True:
try:
address, cursor_id, conn_mgr = self.__kill_cursors_queue.pop()
except IndexError:
break
if conn_mgr:
pinned_cursors.append((address, cursor_id, conn_mgr))
else:
address_to_cursor_ids[address].append(cursor_id)
for address, cursor_id, conn_mgr in pinned_cursors:
try:
self._cleanup_cursor(True, cursor_id, address, conn_mgr, None, False)
except Exception as exc:
if isinstance(exc, InvalidOperation) and self._topology._closed:
# Raise the exception when client is closed so that it
# can be caught in _process_periodic_tasks
raise
else:
helpers._handle_exception()
# Don't re-open topology if it's closed and there's no pending cursors.
if address_to_cursor_ids:
topology = self._get_topology()
for address, cursor_ids in address_to_cursor_ids.items():
try:
self._kill_cursors(cursor_ids, address, topology, session=None)
except Exception as exc:
if isinstance(exc, InvalidOperation) and self._topology._closed:
raise
else:
helpers._handle_exception()
# This method is run periodically by a background thread.
def _process_periodic_tasks(self) -> None:
"""Process any pending kill cursors requests and
maintain connection pool parameters.
"""
try:
self._process_kill_cursors()
self._topology.update_pool()
except Exception as exc:
if isinstance(exc, InvalidOperation) and self._topology._closed:
return
else:
helpers._handle_exception()
def __start_session(self, implicit: bool, **kwargs: Any) -> ClientSession:
server_session = _EmptyServerSession()
opts = client_session.SessionOptions(**kwargs)
return client_session.ClientSession(self, server_session, opts, implicit)
def start_session(
self,
causal_consistency: Optional[bool] = None,
default_transaction_options: Optional[client_session.TransactionOptions] = None,
snapshot: Optional[bool] = False,
) -> client_session.ClientSession:
"""Start a logical session.
This method takes the same parameters as
:class:`~pymongo.client_session.SessionOptions`. See the
:mod:`~pymongo.client_session` module for details and examples.
A :class:`~pymongo.client_session.ClientSession` may only be used with
the MongoClient that started it. :class:`ClientSession` instances are
**not thread-safe or fork-safe**. They can only be used by one thread
or process at a time. A single :class:`ClientSession` cannot be used
to run multiple operations concurrently.
:return: An instance of :class:`~pymongo.client_session.ClientSession`.
.. versionadded:: 3.6
"""
return self.__start_session(
False,
causal_consistency=causal_consistency,
default_transaction_options=default_transaction_options,
snapshot=snapshot,
)
def _return_server_session(
self, server_session: Union[_ServerSession, _EmptyServerSession]
) -> None:
"""Internal: return a _ServerSession to the pool."""
if isinstance(server_session, _EmptyServerSession):
return None
return self._topology.return_server_session(server_session)
def _ensure_session(self, session: Optional[ClientSession] = None) -> Optional[ClientSession]:
"""If provided session is None, lend a temporary session."""
if session:
return session
try:
# Don't make implicit sessions causally consistent. Applications
# should always opt-in.
return self.__start_session(True, causal_consistency=False)
except (ConfigurationError, InvalidOperation):
# Sessions not supported.
return None
@contextlib.contextmanager
def _tmp_session(
self, session: Optional[client_session.ClientSession], close: bool = True
) -> Generator[Optional[client_session.ClientSession], None, None]:
"""If provided session is None, lend a temporary session."""
if session is not None:
if not isinstance(session, client_session.ClientSession):
raise ValueError("'session' argument must be a ClientSession or None.")
# Don't call end_session.
yield session
return
s = self._ensure_session(session)
if s:
try:
yield s
except Exception as exc:
if isinstance(exc, ConnectionFailure):
s._server_session.mark_dirty()
# Always call end_session on error.
s.end_session()
raise
finally:
# Call end_session when we exit this scope.
if close:
s.end_session()
else:
yield None
def _send_cluster_time(
self, command: MutableMapping[str, Any], session: Optional[ClientSession]
) -> None:
topology_time = self._topology.max_cluster_time()
session_time = session.cluster_time if session else None
if topology_time and session_time:
if topology_time["clusterTime"] > session_time["clusterTime"]:
cluster_time: Optional[ClusterTime] = topology_time
else:
cluster_time = session_time
else:
cluster_time = topology_time or session_time
if cluster_time:
command["$clusterTime"] = cluster_time
def _process_response(self, reply: Mapping[str, Any], session: Optional[ClientSession]) -> None:
self._topology.receive_cluster_time(reply.get("$clusterTime"))
if session is not None:
session._process_response(reply)
def server_info(self, session: Optional[client_session.ClientSession] = None) -> dict[str, Any]:
"""Get information about the MongoDB server we're connected to.
:param session: a
:class:`~pymongo.client_session.ClientSession`.
.. versionchanged:: 3.6
Added ``session`` parameter.
"""
return cast(
dict,
self.admin.command(
"buildinfo", read_preference=ReadPreference.PRIMARY, session=session
),
)
def list_databases(
self,
session: Optional[client_session.ClientSession] = None,
comment: Optional[Any] = None,
**kwargs: Any,
) -> CommandCursor[dict[str, Any]]:
"""Get a cursor over the databases of the connected server.
:param session: a
:class:`~pymongo.client_session.ClientSession`.
:param comment: A user-provided comment to attach to this
command.
:param kwargs: Optional parameters of the
`listDatabases command
<https://mongodb.com/docs/manual/reference/command/listDatabases/>`_
can be passed as keyword arguments to this method. The supported
options differ by server version.
:return: An instance of :class:`~pymongo.command_cursor.CommandCursor`.
.. versionadded:: 3.6
"""
cmd = {"listDatabases": 1}
cmd.update(kwargs)
if comment is not None:
cmd["comment"] = comment
admin = self._database_default_options("admin")
res = admin._retryable_read_command(cmd, session=session, operation=_Op.LIST_DATABASES)
# listDatabases doesn't return a cursor (yet). Fake one.
cursor = {
"id": 0,
"firstBatch": res["databases"],
"ns": "admin.$cmd",
}
return CommandCursor(admin["$cmd"], cursor, None, comment=comment)
def list_database_names(
self,
session: Optional[client_session.ClientSession] = None,
comment: Optional[Any] = None,
) -> list[str]:
"""Get a list of the names of all databases on the connected server.
:param session: a
:class:`~pymongo.client_session.ClientSession`.
:param comment: A user-provided comment to attach to this
command.
.. versionchanged:: 4.1
Added ``comment`` parameter.
.. versionadded:: 3.6
"""
return [doc["name"] for doc in self.list_databases(session, nameOnly=True, comment=comment)]
@_csot.apply
def drop_database(
self,
name_or_database: Union[str, database.Database[_DocumentTypeArg]],
session: Optional[client_session.ClientSession] = None,
comment: Optional[Any] = None,
) -> None:
"""Drop a database.
Raises :class:`TypeError` if `name_or_database` is not an instance of
:class:`str` or :class:`~pymongo.database.Database`.
:param name_or_database: the name of a database to drop, or a
:class:`~pymongo.database.Database` instance representing the
database to drop
:param session: a
:class:`~pymongo.client_session.ClientSession`.
:param comment: A user-provided comment to attach to this
command.
.. versionchanged:: 4.1
Added ``comment`` parameter.
.. versionchanged:: 3.6
Added ``session`` parameter.
.. note:: The :attr:`~pymongo.mongo_client.MongoClient.write_concern` of
this client is automatically applied to this operation.
.. versionchanged:: 3.4
Apply this client's write concern automatically to this operation
when connected to MongoDB >= 3.4.
"""
name = name_or_database
if isinstance(name, database.Database):
name = name.name
if not isinstance(name, str):
raise TypeError("name_or_database must be an instance of str or a Database")
with self._conn_for_writes(session, operation=_Op.DROP_DATABASE) as conn:
self[name]._command(
conn,
{"dropDatabase": 1, "comment": comment},
read_preference=ReadPreference.PRIMARY,
write_concern=self._write_concern_for(session),
parse_write_concern_error=True,
session=session,
)
def get_default_database(
self,
default: Optional[str] = None,
codec_options: Optional[CodecOptions[_DocumentTypeArg]] = None,
read_preference: Optional[_ServerMode] = None,
write_concern: Optional[WriteConcern] = None,
read_concern: Optional[ReadConcern] = None,
) -> database.Database[_DocumentType]:
"""Get the database named in the MongoDB connection URI.
>>> uri = 'mongodb://host/my_database'
>>> client = MongoClient(uri)
>>> db = client.get_default_database()
>>> assert db.name == 'my_database'
>>> db = client.get_database()
>>> assert db.name == 'my_database'
Useful in scripts where you want to choose which database to use
based only on the URI in a configuration file.
:param default: the database name to use if no database name
was provided in the URI.
:param codec_options: An instance of
:class:`~bson.codec_options.CodecOptions`. If ``None`` (the
default) the :attr:`codec_options` of this :class:`MongoClient` is
used.
:param read_preference: The read preference to use. If
``None`` (the default) the :attr:`read_preference` of this
:class:`MongoClient` is used. See :mod:`~pymongo.read_preferences`
for options.
:param write_concern: An instance of
:class:`~pymongo.write_concern.WriteConcern`. If ``None`` (the
default) the :attr:`write_concern` of this :class:`MongoClient` is
used.
:param read_concern: An instance of
:class:`~pymongo.read_concern.ReadConcern`. If ``None`` (the
default) the :attr:`read_concern` of this :class:`MongoClient` is
used.
:param comment: A user-provided comment to attach to this
command.
.. versionchanged:: 4.1
Added ``comment`` parameter.
.. versionchanged:: 3.8
Undeprecated. Added the ``default``, ``codec_options``,
``read_preference``, ``write_concern`` and ``read_concern``
parameters.
.. versionchanged:: 3.5
Deprecated, use :meth:`get_database` instead.
"""
if self.__default_database_name is None and default is None:
raise ConfigurationError("No default database name defined or provided.")
name = cast(str, self.__default_database_name or default)
return database.Database(
self, name, codec_options, read_preference, write_concern, read_concern
)
def get_database(
self,
name: Optional[str] = None,
codec_options: Optional[CodecOptions[_DocumentTypeArg]] = None,
read_preference: Optional[_ServerMode] = None,
write_concern: Optional[WriteConcern] = None,
read_concern: Optional[ReadConcern] = None,
) -> database.Database[_DocumentType]:
"""Get a :class:`~pymongo.database.Database` with the given name and
options.
Useful for creating a :class:`~pymongo.database.Database` with
different codec options, read preference, and/or write concern from
this :class:`MongoClient`.
>>> client.read_preference
Primary()
>>> db1 = client.test
>>> db1.read_preference
Primary()
>>> from pymongo import ReadPreference
>>> db2 = client.get_database(
... 'test', read_preference=ReadPreference.SECONDARY)
>>> db2.read_preference
Secondary(tag_sets=None)
:param name: The name of the database - a string. If ``None``
(the default) the database named in the MongoDB connection URI is
returned.
:param codec_options: An instance of
:class:`~bson.codec_options.CodecOptions`. If ``None`` (the
default) the :attr:`codec_options` of this :class:`MongoClient` is
used.
:param read_preference: The read preference to use. If
``None`` (the default) the :attr:`read_preference` of this
:class:`MongoClient` is used. See :mod:`~pymongo.read_preferences`
for options.
:param write_concern: An instance of
:class:`~pymongo.write_concern.WriteConcern`. If ``None`` (the
default) the :attr:`write_concern` of this :class:`MongoClient` is
used.
:param read_concern: An instance of
:class:`~pymongo.read_concern.ReadConcern`. If ``None`` (the
default) the :attr:`read_concern` of this :class:`MongoClient` is
used.
.. versionchanged:: 3.5
The `name` parameter is now optional, defaulting to the database
named in the MongoDB connection URI.
"""
if name is None:
if self.__default_database_name is None:
raise ConfigurationError("No default database defined")
name = self.__default_database_name
return database.Database(
self, name, codec_options, read_preference, write_concern, read_concern
)
def _database_default_options(self, name: str) -> Database:
"""Get a Database instance with the default settings."""
return self.get_database(
name,
codec_options=DEFAULT_CODEC_OPTIONS,
read_preference=ReadPreference.PRIMARY,
write_concern=DEFAULT_WRITE_CONCERN,
)
def __enter__(self) -> MongoClient[_DocumentType]:
return self
def __exit__(self, exc_type: Any, exc_val: Any, exc_tb: Any) -> None:
self.close()
# See PYTHON-3084.
__iter__ = None
def __next__(self) -> NoReturn:
raise TypeError("'MongoClient' object is not iterable")
next = __next__
def _retryable_error_doc(exc: PyMongoError) -> Optional[Mapping[str, Any]]:
"""Return the server response from PyMongo exception or None."""
if isinstance(exc, BulkWriteError):
# Check the last writeConcernError to determine if this
# BulkWriteError is retryable.
wces = exc.details["writeConcernErrors"]
return wces[-1] if wces else None
if isinstance(exc, (NotPrimaryError, OperationFailure)):
return cast(Mapping[str, Any], exc.details)
return None
def _add_retryable_write_error(exc: PyMongoError, max_wire_version: int, is_mongos: bool) -> None:
doc = _retryable_error_doc(exc)
if doc:
code = doc.get("code", 0)
# retryWrites on MMAPv1 should raise an actionable error.
if code == 20 and str(exc).startswith("Transaction numbers"):
errmsg = (
"This MongoDB deployment does not support "
"retryable writes. Please add retryWrites=false "
"to your connection string."
)
raise OperationFailure(errmsg, code, exc.details) # type: ignore[attr-defined]
if max_wire_version >= 9:
# In MongoDB 4.4+, the server reports the error labels.
for label in doc.get("errorLabels", []):
exc._add_error_label(label)
else:
# Do not consult writeConcernError for pre-4.4 mongos.
if isinstance(exc, WriteConcernError) and is_mongos:
pass
elif code in helpers._RETRYABLE_ERROR_CODES:
exc._add_error_label("RetryableWriteError")
# Connection errors are always retryable except NotPrimaryError and WaitQueueTimeoutError which is
# handled above.
if isinstance(exc, ConnectionFailure) and not isinstance(
exc, (NotPrimaryError, WaitQueueTimeoutError)
):
exc._add_error_label("RetryableWriteError")
class _MongoClientErrorHandler:
"""Handle errors raised when executing an operation."""
__slots__ = (
"client",
"server_address",
"session",
"max_wire_version",
"sock_generation",
"completed_handshake",
"service_id",
"handled",
)
def __init__(self, client: MongoClient, server: Server, session: Optional[ClientSession]):
self.client = client
self.server_address = server.description.address
self.session = session
self.max_wire_version = common.MIN_WIRE_VERSION
# XXX: When get_socket fails, this generation could be out of date:
# "Note that when a network error occurs before the handshake
# completes then the error's generation number is the generation
# of the pool at the time the connection attempt was started."
self.sock_generation = server.pool.gen.get_overall()
self.completed_handshake = False
self.service_id: Optional[ObjectId] = None
self.handled = False
def contribute_socket(self, conn: Connection, completed_handshake: bool = True) -> None:
"""Provide socket information to the error handler."""
self.max_wire_version = conn.max_wire_version
self.sock_generation = conn.generation
self.service_id = conn.service_id
self.completed_handshake = completed_handshake
def handle(
self, exc_type: Optional[Type[BaseException]], exc_val: Optional[BaseException]
) -> None:
if self.handled or exc_val is None:
return
self.handled = True
if self.session:
if isinstance(exc_val, ConnectionFailure):
if self.session.in_transaction:
exc_val._add_error_label("TransientTransactionError")
self.session._server_session.mark_dirty()
if isinstance(exc_val, PyMongoError):
if exc_val.has_error_label("TransientTransactionError") or exc_val.has_error_label(
"RetryableWriteError"
):
self.session._unpin()
err_ctx = _ErrorContext(
exc_val,
self.max_wire_version,
self.sock_generation,
self.completed_handshake,
self.service_id,
)
self.client._topology.handle_error(self.server_address, err_ctx)
def __enter__(self) -> _MongoClientErrorHandler:
return self
def __exit__(
self,
exc_type: Optional[Type[Exception]],
exc_val: Optional[Exception],
exc_tb: Optional[TracebackType],
) -> None:
return self.handle(exc_type, exc_val)
class _ClientConnectionRetryable(Generic[T]):
"""Responsible for executing retryable connections on read or write operations"""
def __init__(
self,
mongo_client: MongoClient,
func: _WriteCall[T] | _ReadCall[T],
bulk: Optional[_Bulk],
operation: str,
is_read: bool = False,
session: Optional[ClientSession] = None,
read_pref: Optional[_ServerMode] = None,
address: Optional[_Address] = None,
retryable: bool = False,
operation_id: Optional[int] = None,
):
self._last_error: Optional[Exception] = None
self._retrying = False
self._multiple_retries = _csot.get_timeout() is not None
self._client = mongo_client
self._func = func
self._bulk = bulk
self._session = session
self._is_read = is_read
self._retryable = retryable
self._read_pref = read_pref
self._server_selector: Callable[[Selection], Selection] = (
read_pref if is_read else writable_server_selector # type: ignore
)
self._address = address
self._server: Server = None # type: ignore
self._deprioritized_servers: list[Server] = []
self._operation = operation
self._operation_id = operation_id
def run(self) -> T:
"""Runs the supplied func() and attempts a retry
:raises: self._last_error: Last exception raised
:return: Result of the func() call
"""
# Increment the transaction id up front to ensure any retry attempt
# will use the proper txnNumber, even if server or socket selection
# fails before the command can be sent.
if self._is_session_state_retryable() and self._retryable and not self._is_read:
self._session._start_retryable_write() # type: ignore
if self._bulk:
self._bulk.started_retryable_write = True
while True:
self._check_last_error(check_csot=True)
try:
return self._read() if self._is_read else self._write()
except ServerSelectionTimeoutError:
# The application may think the write was never attempted
# if we raise ServerSelectionTimeoutError on the retry
# attempt. Raise the original exception instead.
self._check_last_error()
# A ServerSelectionTimeoutError error indicates that there may
# be a persistent outage. Attempting to retry in this case will
# most likely be a waste of time.
raise
except PyMongoError as exc:
# Execute specialized catch on read
if self._is_read:
if isinstance(exc, (ConnectionFailure, OperationFailure)):
# ConnectionFailures do not supply a code property
exc_code = getattr(exc, "code", None)
if self._is_not_eligible_for_retry() or (
isinstance(exc, OperationFailure)
and exc_code not in helpers._RETRYABLE_ERROR_CODES
):
raise
self._retrying = True
self._last_error = exc
else:
raise
# Specialized catch on write operation
if not self._is_read:
if not self._retryable:
raise
retryable_write_error_exc = exc.has_error_label("RetryableWriteError")
if retryable_write_error_exc:
assert self._session
self._session._unpin()
if not retryable_write_error_exc or self._is_not_eligible_for_retry():
if exc.has_error_label("NoWritesPerformed") and self._last_error:
raise self._last_error from exc
else:
raise
if self._bulk:
self._bulk.retrying = True
else:
self._retrying = True
if not exc.has_error_label("NoWritesPerformed"):
self._last_error = exc
if self._last_error is None:
self._last_error = exc
if self._client.topology_description.topology_type == TOPOLOGY_TYPE.Sharded:
self._deprioritized_servers.append(self._server)
def _is_not_eligible_for_retry(self) -> bool:
"""Checks if the exchange is not eligible for retry"""
return not self._retryable or (self._is_retrying() and not self._multiple_retries)
def _is_retrying(self) -> bool:
"""Checks if the exchange is currently undergoing a retry"""
return self._bulk.retrying if self._bulk else self._retrying
def _is_session_state_retryable(self) -> bool:
"""Checks if provided session is eligible for retry
reads: Make sure there is no ongoing transaction (if provided a session)
writes: Make sure there is a session without an active transaction
"""
if self._is_read:
return not (self._session and self._session.in_transaction)
return bool(self._session and not self._session.in_transaction)
def _check_last_error(self, check_csot: bool = False) -> None:
"""Checks if the ongoing client exchange experienced a exception previously.
If so, raise last error
:param check_csot: Checks CSOT to ensure we are retrying with time remaining defaults to False
"""
if self._is_retrying():
remaining = _csot.remaining()
if not check_csot or (remaining is not None and remaining <= 0):
assert self._last_error is not None
raise self._last_error
def _get_server(self) -> Server:
"""Retrieves a server object based on provided object context
:return: Abstraction to connect to server
"""
return self._client._select_server(
self._server_selector,
self._session,
self._operation,
address=self._address,
deprioritized_servers=self._deprioritized_servers,
operation_id=self._operation_id,
)
def _write(self) -> T:
"""Wrapper method for write-type retryable client executions
:return: Output for func()'s call
"""
try:
max_wire_version = 0
is_mongos = False
self._server = self._get_server()
with self._client._checkout(self._server, self._session) as conn:
max_wire_version = conn.max_wire_version
sessions_supported = (
self._session
and self._server.description.retryable_writes_supported
and conn.supports_sessions
)
is_mongos = conn.is_mongos
if not sessions_supported:
# A retry is not possible because this server does
# not support sessions raise the last error.
self._check_last_error()
self._retryable = False
return self._func(self._session, conn, self._retryable) # type: ignore
except PyMongoError as exc:
if not self._retryable:
raise
# Add the RetryableWriteError label, if applicable.
_add_retryable_write_error(exc, max_wire_version, is_mongos)
raise
def _read(self) -> T:
"""Wrapper method for read-type retryable client executions
:return: Output for func()'s call
"""
self._server = self._get_server()
assert self._read_pref is not None, "Read Preference required on read calls"
with self._client._conn_from_server(self._read_pref, self._server, self._session) as (
conn,
read_pref,
):
if self._retrying and not self._retryable:
self._check_last_error()
return self._func(self._session, self._server, conn, read_pref) # type: ignore
def _after_fork_child() -> None:
"""Releases the locks in child process and resets the
topologies in all MongoClients.
"""
# Reinitialize locks
_release_locks()
# Perform cleanup in clients (i.e. get rid of topology)
for _, client in MongoClient._clients.items():
client._after_fork()
def _detect_external_db(entity: str) -> bool:
"""Detects external database hosts and logs an informational message at the INFO level."""
entity = entity.lower()
cosmos_db_hosts = [".cosmos.azure.com"]
document_db_hosts = [".docdb.amazonaws.com", ".docdb-elastic.amazonaws.com"]
for host in cosmos_db_hosts:
if entity.endswith(host):
_log_or_warn(
_CLIENT_LOGGER,
"You appear to be connected to a CosmosDB cluster. For more information regarding feature "
"compatibility and support please visit https://www.mongodb.com/supportability/cosmosdb",
)
return True
for host in document_db_hosts:
if entity.endswith(host):
_log_or_warn(
_CLIENT_LOGGER,
"You appear to be connected to a DocumentDB cluster. For more information regarding feature "
"compatibility and support please visit https://www.mongodb.com/supportability/documentdb",
)
return True
return False
if _HAS_REGISTER_AT_FORK:
# This will run in the same thread as the fork was called.
# If we fork in a critical region on the same thread, it should break.
# This is fine since we would never call fork directly from a critical region.
os.register_at_fork(after_in_child=_after_fork_child)