# Copyright (c) "Neo4j" # Neo4j Sweden AB [https://neo4j.com] # # 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 # # https://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from __future__ import annotations import asyncio from types import NoneType from .. import _typing as t from .._addressing import Address from .._api import ( DRIVER_BOLT, DRIVER_NEO4J, NotificationMinimumSeverity, parse_neo4j_uri, parse_routing_context, RoutingControl, SECURITY_TYPE_SECURE, SECURITY_TYPE_SELF_SIGNED_CERTIFICATE, TelemetryAPI, ) from .._conf import ( Config, ConfigurationError, SessionConfig, TrustAll, TrustStore, WorkspaceConfig, ) from .._debug import ENABLED as DEBUG_ENABLED from .._warnings import ( deprecation_warn, preview_warn, unclosed_resource_warn, ) from .._work import ( EagerResult, Query, unit_of_work, ) from ..api import ( _TAuth, Auth, BookmarkManager, Bookmarks, READ_ACCESS, ServerInfo, URI_SCHEME_BOLT, URI_SCHEME_BOLT_SECURE, URI_SCHEME_BOLT_SELF_SIGNED_CERTIFICATE, URI_SCHEME_NEO4J, URI_SCHEME_NEO4J_SECURE, URI_SCHEME_NEO4J_SELF_SIGNED_CERTIFICATE, WRITE_ACCESS, ) from ..auth_management import ( AuthManager, AuthManagers, ClientCertificate, ClientCertificateProvider, ) from ..exceptions import ( DriverError, Neo4jError, ) from .auth_management import _StaticClientCertificateProvider from .bookmark_manager import ( Neo4jBookmarkManager, TBmConsumer as _TBmConsumer, TBmSupplier as _TBmSupplier, ) from .config import PoolConfig from .work import ( ManagedTransaction, Result, Session, ) if t.TYPE_CHECKING: import ssl from enum import Enum from .._api import ( T_NotificationDisabledClassification, T_NotificationMinimumSeverity, T_RoutingControl, ) class _DefaultEnum(Enum): default = "default" _default = _DefaultEnum.default else: _default = object() _T = t.TypeVar("_T") class GraphDatabase: """Accessor for :class:`neo4j.Driver` construction.""" if t.TYPE_CHECKING: @classmethod def driver( cls, uri: str, *, auth: _TAuth | AuthManager = ..., max_connection_lifetime: float = ..., liveness_check_timeout: float | None = ..., max_connection_pool_size: int = ..., connection_timeout: float = ..., connection_write_timeout: float = ..., resolver: ( t.Callable[[Address], t.Iterable[Address]] | t.Callable[[Address], t.Union[t.Iterable[Address]]] ) = ..., encrypted: bool = ..., trusted_certificates: TrustStore = ..., client_certificate: ( ClientCertificate | ClientCertificateProvider | None ) = ..., ssl_context: ssl.SSLContext | None = ..., user_agent: str = ..., keep_alive: bool = ..., notifications_min_severity: ( T_NotificationMinimumSeverity | None ) = ..., # deprecated in favor of notifications_disabled_classifications notifications_disabled_categories: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., notifications_disabled_classifications: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., warn_notification_severity: ( T_NotificationMinimumSeverity | None ) = ..., telemetry_disabled: bool = ..., max_transaction_retry_time: float = ..., connection_acquisition_timeout: float = ..., # undocumented/unsupported options # they may be changed or removed any time without prior notice initial_retry_delay: float = ..., retry_delay_multiplier: float = ..., retry_delay_jitter_factor: float = ..., database: str | None = ..., fetch_size: int = ..., impersonated_user: str | None = ..., bookmark_manager: ( BookmarkManager | BookmarkManager | None ) = ..., ) -> Driver: ... else: @classmethod def driver( cls, uri: str, *, auth: _TAuth | AuthManager = None, **config, ) -> Driver: """ Create a driver. :param uri: the connection URI for the driver, see :ref:`uri-ref` for available URIs. :param auth: the authentication details, see :ref:`auth-ref` for available authentication details. :param config: driver configuration key-word arguments, see :ref:`driver-configuration-ref` for available key-word arguments. """ driver_type, security_type, parsed = parse_neo4j_uri(uri) if not isinstance(auth, AuthManager): auth = AuthManagers.static(auth) config["auth"] = auth client_certificate = config.get("client_certificate") if isinstance(client_certificate, ClientCertificate): # using internal class until public factory is GA: # AsyncClientCertificateProviders.static config["client_certificate"] = ( _StaticClientCertificateProvider(client_certificate) ) if "trusted_certificates" in config and not isinstance( config["trusted_certificates"], TrustStore ): raise ConfigurationError( 'The config setting "trusted_certificates" must be of ' "type neo4j.TrustAll, neo4j.TrustCustomCAs, or" "neo4j.TrustSystemCAs but was {}".format( type(config["trusted_certificates"]) ) ) if security_type in { SECURITY_TYPE_SELF_SIGNED_CERTIFICATE, SECURITY_TYPE_SECURE, } and ( "encrypted" in config or "trusted_certificates" in config or "ssl_context" in config ): raise ConfigurationError( 'The config settings "encrypted", "trusted_certificates", ' 'and "ssl_context" can only be used with the URI schemes ' "{!r}. Use the other URI schemes {!r} for setting " "encryption settings.".format( [ URI_SCHEME_BOLT, URI_SCHEME_NEO4J, ], [ URI_SCHEME_BOLT_SELF_SIGNED_CERTIFICATE, URI_SCHEME_BOLT_SECURE, URI_SCHEME_NEO4J_SELF_SIGNED_CERTIFICATE, URI_SCHEME_NEO4J_SECURE, ], ) ) if security_type == SECURITY_TYPE_SECURE: config["encrypted"] = True elif security_type == SECURITY_TYPE_SELF_SIGNED_CERTIFICATE: config["encrypted"] = True config["trusted_certificates"] = TrustAll() if "notifications_disabled_categories" in config: deprecation_warn( "notifications_disabled_categories is deprecated, " "use notifications_disabled_classifications instead.", stack_level=2, ) _normalize_notifications_config(config, driver_level=True) liveness_check_timeout = config.get("liveness_check_timeout") if ( liveness_check_timeout is not None and liveness_check_timeout < 0 ): raise ConfigurationError( 'The config setting "liveness_check_timeout" must be ' "greater than or equal to 0 but was " f"{liveness_check_timeout}." ) assert driver_type in {DRIVER_BOLT, DRIVER_NEO4J} if driver_type == DRIVER_BOLT: if parse_routing_context(parsed.query): raise ConfigurationError( "Routing context (URI query parameters) are not " "supported by direct drivers " f'("bolt[+s[sc]]://" scheme). Given URI: {uri!r}.' ) return cls._bolt_driver(parsed.netloc, **config) # else driver_type == DRIVER_NEO4J routing_context = parse_routing_context(parsed.query) return cls._neo4j_driver( parsed.netloc, routing_context=routing_context, **config ) @classmethod def bookmark_manager( cls, initial_bookmarks: Bookmarks | t.Iterable[str] | None = None, bookmarks_supplier: _TBmSupplier | None = None, bookmarks_consumer: _TBmConsumer | None = None, ) -> BookmarkManager: """ Create a :class:`.BookmarkManager` with default implementation. Basic usage example to configure sessions with the built-in bookmark manager implementation so that all work is automatically causally chained (i.e., all reads can observe all previous writes even in a clustered setup):: import neo4j # omitting closing the driver for brevity driver = neo4j.GraphDatabase.driver(...) bookmark_manager = neo4j.GraphDatabase.bookmark_manager(...) with ( driver.session(bookmark_manager=bookmark_manager) as session1, driver.session( bookmark_manager=bookmark_manager, default_access_mode=neo4j.READ_ACCESS, ) as session2, ): result1 = session1.run("") result1.consume() # READ_QUERY is guaranteed to see what WRITE_QUERY wrote. result2 = session2.run("") result2.consume() This is a very contrived example, and in this particular case, having both queries in the same session has the exact same effect and might even be more performant. However, when dealing with sessions spanning multiple threads, Tasks, processes, or even hosts, the bookmark manager can come in handy as sessions are not safe to be used concurrently. :param initial_bookmarks: The initial set of bookmarks. The returned bookmark manager will use this to initialize its internal bookmarks. .. deprecated:: 6.0 Passing raw string bookmarks is deprecated. Use a :class:`.Bookmarks` object instead. :param bookmarks_supplier: Function which will be called every time the default bookmark manager's method :meth:`.BookmarkManager.get_bookmarks` gets called. The function takes no arguments and must return a :class:`.Bookmarks` object. The result of ``bookmarks_supplier`` will then be concatenated with the internal set of bookmarks and used to configure the session in creation. It will, however, not update the internal set of bookmarks. :param bookmarks_consumer: Function which will be called whenever the set of bookmarks handled by the bookmark manager gets updated with the new internal bookmark set. It will receive the new set of bookmarks as a :class:`.Bookmarks` object and return :data:`None`. :returns: A default implementation of :class:`.BookmarkManager`. .. versionadded:: 5.0 .. versionchanged:: 5.3 The bookmark manager no longer tracks bookmarks per database. This effectively changes the signature of almost all bookmark manager related methods: * ``initial_bookmarks`` is no longer a mapping from database name to bookmarks but plain bookmarks. * ``bookmarks_supplier`` no longer receives the database name as an argument. * ``bookmarks_consumer`` no longer receives the database name as an argument. .. versionchanged:: 5.8 Stabilized from experimental. .. versionchanged:: 6.0 Deprecated passing raw string bookmarks as initial_bookmarks. """ cast_initial_bookmarks: Bookmarks | None # TODO: 7.0 - remove raw bookmark support if not isinstance(initial_bookmarks, (Bookmarks, NoneType)): deprecation_warn( ( "Passing raw strings as initial_bookmarks is deprecated. " "Use a Bookmarks object instead." ), stack_level=2, ) cast_initial_bookmarks = Bookmarks.from_raw_values( t.cast(t.Iterable[str], initial_bookmarks) ) else: cast_initial_bookmarks = initial_bookmarks return Neo4jBookmarkManager( initial_bookmarks=cast_initial_bookmarks, bookmarks_supplier=bookmarks_supplier, bookmarks_consumer=bookmarks_consumer, ) @classmethod def _bolt_driver(cls, target, **config): """ Create a direct driver. Create a driver for direct Bolt server access that uses socket I/O and thread-based concurrency. """ from .._exceptions import ( BoltHandshakeError, BoltSecurityError, ) try: return BoltDriver._open(target, **config) except (BoltHandshakeError, BoltSecurityError) as error: from ..exceptions import ServiceUnavailable raise ServiceUnavailable(str(error)) from error @classmethod def _neo4j_driver(cls, target, routing_context=None, **config): """ Create a routing driver. Create a driver for routing-capable Neo4j service access that uses socket I/O and thread-based concurrency. """ from .._exceptions import ( BoltHandshakeError, BoltSecurityError, ) try: return Neo4jDriver._open( target, routing_context=routing_context, **config ) except (BoltHandshakeError, BoltSecurityError) as error: from ..exceptions import ServiceUnavailable raise ServiceUnavailable(str(error)) from error class _Direct: _default_host = "localhost" _default_port = 7687 _default_target = ":" def __init__(self, address): self._address = address @property def address(self): return self._address @classmethod def _parse_target(cls, target): """Parse a target string to produce an address.""" if not target: target = cls._default_target return Address.parse( target, default_host=cls._default_host, default_port=cls._default_port, ) class _Routing: _default_host = "localhost" _default_port = 7687 _default_targets = ": :17601 :17687" def __init__(self, initial_addresses): self._initial_addresses = initial_addresses @property def initial_addresses(self): return self._initial_addresses @classmethod def _parse_targets(cls, *targets): """Parse a sequence of target strings to produce an address list.""" targets = " ".join(targets) if not targets: targets = cls._default_targets return Address.parse_list( targets, default_host=cls._default_host, default_port=cls._default_port, ) class Driver: """ Base class for all driver types. Drivers are used as the primary access point to Neo4j. """ #: Connection pool _pool: t.Any = None #: Flag if the driver has been closed _closed = False def __init__(self, pool, default_workspace_config): assert pool is not None assert default_workspace_config is not None self._pool = pool self._default_workspace_config = default_workspace_config self._query_bookmark_manager = GraphDatabase.bookmark_manager() def __enter__(self) -> Driver: return self def __exit__(self, exc_type, exc_value, traceback): self.close() # Copy globals as function locals to make sure that they are available # during Python shutdown when the Pool is destroyed. def __del__( self, _unclosed_resource_warn=unclosed_resource_warn, ): if not self._closed: _unclosed_resource_warn(self) def _check_state(self): if self._closed: raise DriverError("Driver closed") @property def encrypted(self) -> bool: """Indicate whether the driver was configured to use encryption.""" return bool(self._pool.pool_config.encrypted) if t.TYPE_CHECKING: def session( self, *, connection_acquisition_timeout: float = ..., max_transaction_retry_time: float = ..., database: str | None = ..., fetch_size: int = ..., impersonated_user: str | None = ..., bookmarks: Bookmarks | None = ..., default_access_mode: str = ..., bookmark_manager: ( BookmarkManager | BookmarkManager | None ) = ..., auth: _TAuth = ..., notifications_min_severity: ( T_NotificationMinimumSeverity | None ) = ..., # deprecated in favor of notifications_disabled_classifications notifications_disabled_categories: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., notifications_disabled_classifications: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., # undocumented/unsupported options # they may be change or removed any time without prior notice initial_retry_delay: float = ..., retry_delay_multiplier: float = ..., retry_delay_jitter_factor: float = ..., ) -> Session: ... else: def session(self, **config) -> Session: """ Create a session. See :ref:`session-construction-ref` for details. :param config: session configuration key-word arguments, see :ref:`session-configuration-ref` for available key-word arguments. :returns: new :class:`neo4j.Session` object :raises DriverError: if the driver has been closed. .. versionchanged:: 6.0 * Raise :exc:`DriverError` if the driver has been closed. * Deprecated ``notifications_disabled_categories`` in favor of ``notifications_disabled_classifications``. """ # Would work just fine, but we don't want to introduce yet # another undocumented/unsupported config option. config.pop("warn_notification_severity", None) self._check_state() if "notifications_disabled_categories" in config: deprecation_warn( "notifications_disabled_categories is deprecated, " "use notifications_disabled_classifications instead.", stack_level=2, ) session_config = self._read_session_config(config) return self._session(session_config) def _session(self, session_config) -> Session: return Session(self._pool, session_config) def _read_session_config(self, config_kwargs): config = self._prepare_session_config(config_kwargs) return SessionConfig(self._default_workspace_config, config) @classmethod def _prepare_session_config(cls, config_kwargs): _normalize_notifications_config(config_kwargs) return config_kwargs def close(self) -> None: """Shut down, closing any open connections in the pool. .. warning:: While the driver object is concurrency-safe, ``close`` is *not*. Make sure you are not using the driver object or any resources spawned from it (such as sessions or transactions) while calling this method. Failing to do so results in unspecified behavior. """ if self._closed: return try: self._pool.close() except asyncio.CancelledError: self._closed = True raise self._closed = True # overloads to work around https://github.com/python/mypy/issues/3737 @t.overload def execute_query( self, query_: t.LiteralString | Query, parameters_: dict[str, t.Any] | None = None, routing_: T_RoutingControl = RoutingControl.WRITE, database_: str | None = None, impersonated_user_: str | None = None, bookmark_manager_: ( BookmarkManager | BookmarkManager | None ) = ..., auth_: _TAuth = None, result_transformer_: t.Callable[ [Result], t.Union[EagerResult] ] = ..., **kwargs: t.Any, ) -> EagerResult: ... @t.overload def execute_query( self, query_: t.LiteralString | Query, parameters_: dict[str, t.Any] | None = None, routing_: T_RoutingControl = RoutingControl.WRITE, database_: str | None = None, impersonated_user_: str | None = None, bookmark_manager_: ( BookmarkManager | BookmarkManager | None ) = ..., auth_: _TAuth = None, result_transformer_: t.Callable[[Result], t.Union[_T]] = ..., **kwargs: t.Any, ) -> _T: ... def execute_query( self, query_: t.LiteralString | Query, parameters_: dict[str, t.Any] | None = None, routing_: T_RoutingControl = RoutingControl.WRITE, database_: str | None = None, impersonated_user_: str | None = None, bookmark_manager_: ( BookmarkManager | BookmarkManager | t.Literal[_DefaultEnum.default] | None ) = _default, auth_: _TAuth = None, result_transformer_: t.Callable[ [Result], t.Union[t.Any] ] = Result.to_eager_result, **kwargs: t.Any, ) -> t.Any: ''' Execute a query in a transaction function and return all results. This method is a handy wrapper for lower-level driver APIs like sessions, transactions, and transaction functions. It is intended for simple use cases where there is no need for managing all possible options. The internal usage of transaction functions provides a retry-mechanism for appropriate errors. Furthermore, this means that queries using ``CALL {} IN TRANSACTIONS`` or the older ``USING PERIODIC COMMIT`` will not work (use :meth:`Session.run` for these). The method is roughly equivalent to:: def execute_query( query_, parameters_, routing_, database_, impersonated_user_, bookmark_manager_, auth_, result_transformer_, **kwargs ): @unit_of_work(query_.metadata, query_.timeout) def work(tx): result = tx.run(query_.text, parameters_, **kwargs) return result_transformer_(result) with driver.session( database=database_, impersonated_user=impersonated_user_, bookmark_manager=bookmark_manager_, auth=auth_, ) as session: if routing_ == RoutingControl.WRITE: return session.execute_write(work) elif routing_ == RoutingControl.READ: return session.execute_read(work) Usage example:: from typing import List import neo4j def example(driver: neo4j.Driver) -> List[str]: """Get the name of all 42 year-olds.""" records, summary, keys = driver.execute_query( "MATCH (p:Person {age: $age}) RETURN p.name", {"age": 42}, routing_=neo4j.RoutingControl.READ, # or just "r" database_="neo4j", ) assert keys == ["p.name"] # not needed, just for illustration # log_summary(summary) # log some metadata return [str(record["p.name"]) for record in records] # or: return [str(record[0]) for record in records] # or even: return list(map(lambda r: str(r[0]), records)) Another example:: import neo4j def example(driver: neo4j.Driver) -> int: """Call all young people "My dear" and get their count.""" record = driver.execute_query( "MATCH (p:Person) WHERE p.age <= $age " "SET p.nickname = 'My dear' " "RETURN count(*)", # optional routing parameter, as write is default # routing_=neo4j.RoutingControl.WRITE, # or just "w", database_="neo4j", result_transformer_=neo4j.Result.single, age=15, ) assert record is not None # for typechecking and illustration count = record[0] assert isinstance(count, int) return count :param query_: Cypher query to execute. Use a :class:`.Query` object to pass a query with additional transaction configuration. :type query_: typing.LiteralString | Query :param parameters_: parameters to use in the query :type parameters_: typing.Optional[typing.Dict[str, typing.Any]] :param routing_: Whether to route the query to a reader (follower/read replica) or a writer (leader) in the cluster. Default is to route to a writer. :type routing_: RoutingControl :param database_: Database to execute the query against. :data:`None` (default) uses the database configured on the server side. .. Note:: It is recommended to always specify the database explicitly when possible. This allows the driver to work more efficiently, as it will not have to resolve the default database first. See also the Session config :ref:`database-ref`. :type database_: typing.Optional[str] :param impersonated_user_: Name of the user to impersonate. This means that all query will be executed in the security context of the impersonated user. For this, the user for which the :class:`Driver` has been created needs to have the appropriate permissions. See also the Session config :ref:`impersonated-user-ref`. :type impersonated_user_: typing.Optional[str] :param auth_: Authentication information to use for this query. By default, the driver configuration is used. See also the Session config :ref:`session-auth-ref`. :type auth_: typing.Tuple[typing.Any, typing.Any] | Auth | None :param result_transformer_: A function that gets passed the :class:`neo4j.Result` object resulting from the query and converts it to a different type. The result of the transformer function is returned by this method. .. warning:: The transformer function must **not** return the :class:`neo4j.Result` itself. .. warning:: N.B. the driver might retry the underlying transaction so the transformer might get invoked more than once (with different :class:`neo4j.Result` objects). Therefore, it needs to be idempotent (i.e., have the same effect, regardless if called once or many times). Example transformer that checks that exactly one record is in the result stream, then returns the record and the result summary:: from typing import Tuple import neo4j def transformer( result: neo4j.Result ) -> Tuple[neo4j.Record, neo4j.ResultSummary]: record = result.single(strict=True) summary = result.consume() return record, summary Note that methods of :class:`neo4j.Result` that don't take mandatory arguments can be used directly as transformer functions. For example:: import neo4j def example(driver: neo4j.Driver) -> neo4j.Record:: record = driver.execute_query( "SOME QUERY", result_transformer_=neo4j.Result.single ) # is equivalent to: def transformer(result: neo4j.Result) -> neo4j.Record: return result.single() def example(driver: neo4j.Driver) -> neo4j.Record:: record = driver.execute_query( "SOME QUERY", result_transformer_=transformer ) :type result_transformer_: typing.Callable[[Result], typing.Union[T]] :param bookmark_manager_: Specify a bookmark manager to use. If present, the bookmark manager is used to keep the query causally consistent with all work executed using the same bookmark manager. Defaults to the driver's :attr:`.execute_query_bookmark_manager`. Pass :data:`None` to disable causal consistency. :type bookmark_manager_: BookmarkManager | BookmarkManager | None :param kwargs: additional keyword parameters. None of these can end with a single underscore. This is to avoid collisions with the keyword configuration parameters of this method. If you need to pass such a parameter, use the ``parameters_`` parameter instead. Parameters passed as kwargs take precedence over those passed in ``parameters_``. :type kwargs: typing.Any :returns: the result of the ``result_transformer_`` :rtype: T :raises DriverError: if the driver has been closed. .. versionadded:: 5.5 .. versionchanged:: 5.8 * Added ``auth_`` parameter in preview. * Stabilized from experimental. .. versionchanged:: 5.14 Stabilized ``auth_`` parameter from preview. .. versionchanged:: 5.15 The ``query_`` parameter now also accepts a :class:`.Query` object instead of only :class:`str`. .. versionchanged:: 6.0 Raise :exc:`DriverError` if the driver has been closed. ''' # noqa: E501 example code isn't too long self._check_state() invalid_kwargs = [ k for k in kwargs if k[-2:-1] != "_" and k[-1:] == "_" ] if invalid_kwargs: raise ValueError( "keyword parameters must not end with a single '_'. " f"Found: {invalid_kwargs!r}\n" "\nYou either misspelled an existing configuration parameter " "or tried to send a query parameter that is reserved. In the " "latter case, use the `parameters_` dictionary instead." ) if isinstance(query_, Query): timeout = query_.timeout metadata = query_.metadata query_str = query_.text work = unit_of_work(metadata, timeout)(_work) else: query_str = query_ work = _work parameters = dict(parameters_ or {}, **kwargs) if bookmark_manager_ is _default: bookmark_manager_ = self._query_bookmark_manager assert bookmark_manager_ is not _default session_config = self._read_session_config( { "database": database_, "impersonated_user": impersonated_user_, "bookmark_manager": bookmark_manager_, "auth": auth_, } ) session = self._session(session_config) with session: if routing_ == RoutingControl.WRITE: access_mode = WRITE_ACCESS elif routing_ == RoutingControl.READ: access_mode = READ_ACCESS else: raise ValueError( f"Invalid routing control value: {routing_!r}" ) with session._pipelined_begin: return session._run_transaction( access_mode, TelemetryAPI.DRIVER, work, (query_str, parameters, result_transformer_), {}, ) @property def execute_query_bookmark_manager(self) -> BookmarkManager: """ The driver's default query bookmark manager. This is the default :class:`.BookmarkManager` used by :meth:`.execute_query`. This can be used to causally chain :meth:`.execute_query` calls and sessions. Example:: def example(driver: neo4j.Driver) -> None: driver.execute_query("") with driver.session( bookmark_manager=driver.execute_query_bookmark_manager ) as session: # every query inside this session will be causally chained # (i.e., can read what was written by ) session.run("") # subsequent execute_query calls will be causally chained # (i.e., can read what was written by ) driver.execute_query("") .. versionadded:: 5.5 .. versionchanged:: 5.8 * Renamed from ``query_bookmark_manager`` to ``execute_query_bookmark_manager``. * Stabilized from experimental. """ return self._query_bookmark_manager if t.TYPE_CHECKING: def verify_connectivity( self, *, # all arguments are experimental # they may be change or removed any time without prior notice session_connection_timeout: float = ..., connection_acquisition_timeout: float = ..., max_transaction_retry_time: float = ..., database: str | None = ..., fetch_size: int = ..., impersonated_user: str | None = ..., bookmarks: t.Iterable[str] | Bookmarks | None = ..., default_access_mode: str = ..., bookmark_manager: ( BookmarkManager | BookmarkManager | None ) = ..., auth: Auth | tuple[str, str] = ..., notifications_min_severity: ( T_NotificationMinimumSeverity | None ) = ..., notifications_disabled_categories: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., notifications_disabled_classifications: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., # undocumented/unsupported options initial_retry_delay: float = ..., retry_delay_multiplier: float = ..., retry_delay_jitter_factor: float = ..., ) -> None: ... else: def verify_connectivity(self, **config) -> None: """ Verify that the driver can establish a connection to the server. This verifies if the driver can establish a reading connection to a remote server or a cluster. Some data will be exchanged. .. note:: Even if this method raises an exception, the driver still needs to be closed via :meth:`close` to free up all resources. :param config: accepts the same configuration key-word arguments as :meth:`session`. .. warning:: Passing key-word arguments is a preview feature. It might be changed or removed in any future version without prior notice. :raises Exception: if the driver cannot connect to the remote. Use the exception to further understand the cause of the connectivity problem. :raises DriverError: if the driver has been closed. .. versionchanged:: 5.0 The undocumented return value has been removed. If you need information about the remote server, use :meth:`get_server_info` instead. .. versionchanged:: 6.0 Raise :exc:`DriverError` if the driver has been closed. """ self._check_state() if config: preview_warn( "Passing key-word arguments to verify_connectivity() is a " "preview feature." ) session_config = self._read_session_config(config) self._get_server_info(session_config) if t.TYPE_CHECKING: def get_server_info( self, *, # all arguments are experimental # they may be change or removed any time without prior notice session_connection_timeout: float = ..., connection_acquisition_timeout: float = ..., max_transaction_retry_time: float = ..., database: str | None = ..., fetch_size: int = ..., impersonated_user: str | None = ..., bookmarks: t.Iterable[str] | Bookmarks | None = ..., default_access_mode: str = ..., bookmark_manager: ( BookmarkManager | BookmarkManager | None ) = ..., auth: Auth | tuple[str, str] = ..., notifications_min_severity: ( T_NotificationMinimumSeverity | None ) = ..., notifications_disabled_categories: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., notifications_disabled_classifications: ( t.Iterable[T_NotificationDisabledClassification] | None ) = ..., # undocumented/unsupported options initial_retry_delay: float = ..., retry_delay_multiplier: float = ..., retry_delay_jitter_factor: float = ..., ) -> ServerInfo: ... else: def get_server_info(self, **config) -> ServerInfo: """ Get information about the connected Neo4j server. Try to establish a working read connection to the remote server or a member of a cluster and exchange some data. Then return the contacted server's information. In a cluster, there is no guarantee about which server will be contacted. .. note:: Even if this method raises an exception, the driver still needs to be closed via :meth:`close` to free up all resources. :param config: accepts the same configuration key-word arguments as :meth:`session`. .. warning:: Passing key-word arguments is a preview feature. It might be changed or removed in any future version without prior notice. :raises Exception: if the driver cannot connect to the remote. Use the exception to further understand the cause of the connectivity problem. :raises DriverError: if the driver has been closed. .. versionadded:: 5.0 .. versionchanged:: 6.0 Raise :exc:`DriverError` if the driver has been closed. """ self._check_state() if config: preview_warn( "Passing key-word arguments to get_server_info() is a " "preview feature." ) session_config = self._read_session_config(config) return self._get_server_info(session_config) def supports_multi_db(self) -> bool: """ Check if the server or cluster supports multi-databases. .. note:: Feature support query based solely on the Bolt protocol version. The feature might still be disabled on the server side even if this function return :data:`True`. It just guarantees that the driver won't throw a :exc:`.ConfigurationError` when trying to use this driver feature. :returns: Returns true if the server or cluster the driver connects to supports multi-databases, otherwise false. :raises DriverError: if the driver has been closed. .. versionchanged:: 6.0 Raise :exc:`DriverError` if the driver has been closed. """ self._check_state() session_config = self._read_session_config({}) with self._session(session_config) as session: session._connect(READ_ACCESS) assert session._connection return session._connection.supports_multiple_databases if t.TYPE_CHECKING: def verify_authentication( self, auth: Auth | tuple[str, str] | None = None, # all other arguments are experimental # they may be change or removed any time without prior notice session_connection_timeout: float = ..., connection_acquisition_timeout: float = ..., max_transaction_retry_time: float = ..., database: str | None = ..., fetch_size: int = ..., impersonated_user: str | None = ..., bookmarks: t.Iterable[str] | Bookmarks | None = ..., default_access_mode: str = ..., bookmark_manager: ( BookmarkManager | BookmarkManager | None ) = ..., # undocumented/unsupported options initial_retry_delay: float = ..., retry_delay_multiplier: float = ..., retry_delay_jitter_factor: float = ..., ) -> bool: ... else: def verify_authentication( self, auth: Auth | tuple[str, str] | None = None, **config, ) -> bool: """ Verify that the authentication information is valid. Like :meth:`.verify_connectivity`, but for checking authentication. Try to establish a working read connection to the remote server or a member of a cluster and exchange some data. In a cluster, there is no guarantee about which server will be contacted. If the data exchange is successful and the authentication information is valid, :data:`True` is returned. Otherwise, the error will be matched against a list of known authentication errors. If the error is on that list, :data:`False` is returned indicating that the authentication information is invalid. Otherwise, the error is re-raised. :param auth: authentication information to verify. Same as the session config :ref:`auth-ref`. :param config: accepts the same configuration key-word arguments as :meth:`session`. .. warning:: Passing key-word arguments (except ``auth``) is a preview feature. It might be changed or removed in any future version without prior notice. :raises Exception: if the driver cannot connect to the remote. Use the exception to further understand the cause of the connectivity problem. :raises DriverError: if the driver has been closed. .. versionadded:: 5.8 .. versionchanged:: 5.14 Stabilized from experimental. .. versionchanged:: 6.0 Raise :exc:`DriverError` if the driver has been closed. """ self._check_state() if config: preview_warn( "Passing key-word arguments except 'auth' to " "verify_authentication() is a preview feature." ) if "database" not in config: config["database"] = "system" session_config = self._read_session_config(config) session_config = SessionConfig(session_config, {"auth": auth}) with self._session(session_config) as session: try: session._verify_authentication() except Neo4jError as exc: if exc.code in { "Neo.ClientError.Security.CredentialsExpired", "Neo.ClientError.Security.Forbidden", "Neo.ClientError.Security.TokenExpired", "Neo.ClientError.Security.Unauthorized", }: return False raise return True def supports_session_auth(self) -> bool: """ Check if the remote supports connection re-authentication. .. note:: Feature support query based solely on the Bolt protocol version. The feature might still be disabled on the server side even if this function return :data:`True`. It just guarantees that the driver won't throw a :exc:`.ConfigurationError` when trying to use this driver feature. :returns: Returns true if the server or cluster the driver connects to supports re-authentication of existing connections, otherwise false. :raises DriverError: if the driver has been closed. .. versionadded:: 5.8 .. versionchanged:: 6.0 Raise :exc:`DriverError` if the driver has been closed. """ self._check_state() session_config = self._read_session_config({}) with self._session(session_config) as session: session._connect(READ_ACCESS) assert session._connection return session._connection.supports_re_auth def _get_server_info(self, session_config) -> ServerInfo: with self._session(session_config) as session: return session._get_server_info() def _work( tx: ManagedTransaction, query: t.LiteralString, parameters: dict[str, t.Any], transformer: t.Callable[[Result], t.Union[_T]], ) -> _T: res = tx.run(query, parameters) return transformer(res) class BoltDriver(_Direct, Driver): """ :class:`.BoltDriver` is instantiated for ``bolt`` URIs. It addresses a single database machine. This may be a standalone server or could be a specific member of a cluster. Connections established by a :class:`.BoltDriver` are always made to the exact host and port detailed in the URI. This class is not supposed to be instantiated externally. Use :meth:`GraphDatabase.driver` instead. """ @classmethod def _open(cls, target, **config): from .io import BoltPool address = cls._parse_target(target) pool_config, default_workspace_config = Config.consume_chain( config, PoolConfig, WorkspaceConfig ) pool = BoltPool.open( address, pool_config=pool_config, workspace_config=default_workspace_config, ) return cls(pool, default_workspace_config) def __init__(self, pool, default_workspace_config): _Direct.__init__(self, pool.address) Driver.__init__(self, pool, default_workspace_config) self._default_workspace_config = default_workspace_config class Neo4jDriver(_Routing, Driver): """ :class:`.Neo4jDriver` is instantiated for ``neo4j`` URIs. The routing behaviour works in tandem with Neo4j's `Causal Clustering `_ feature by directing read and write behaviour to appropriate cluster members. This class is not supposed to be instantiated externally. Use :meth:`GraphDatabase.driver` instead. """ @classmethod def _open(cls, *targets, routing_context=None, **config): from .io import Neo4jPool addresses = cls._parse_targets(*targets) pool_config, default_workspace_config = Config.consume_chain( config, PoolConfig, WorkspaceConfig ) pool = Neo4jPool.open( *addresses, routing_context=routing_context, pool_config=pool_config, workspace_config=default_workspace_config, ) return cls(pool, default_workspace_config) def __init__(self, pool, default_workspace_config): _Routing.__init__(self, [pool.address]) Driver.__init__(self, pool, default_workspace_config) def _normalize_notifications_config(config_kwargs, *, driver_level=False): list_config_keys = ( "notifications_disabled_categories", "notifications_disabled_classifications", ) for key in list_config_keys: value = config_kwargs.get(key) if value is not None: config_kwargs[key] = [getattr(e, "value", e) for e in value] disabled_categories = config_kwargs.pop( "notifications_disabled_categories", None ) if disabled_categories is not None: disabled_classifications = config_kwargs.get( "notifications_disabled_classifications" ) if disabled_classifications is None: disabled_classifications = disabled_categories else: disabled_classifications = list( {*disabled_categories, *disabled_classifications} ) config_kwargs["notifications_disabled_classifications"] = ( disabled_classifications ) single_config_keys = ( "notifications_min_severity", "warn_notification_severity", ) for key in single_config_keys: value = config_kwargs.get(key) if value is not None: config_kwargs[key] = getattr(value, "value", value) value = config_kwargs.get("warn_notification_severity") if value not in {*NotificationMinimumSeverity, None}: raise ValueError( f"Invalid value for configuration " f"warn_notification_severity: {value}. Should be None, a " f"NotificationMinimumSeverity, or a string representing a " f"NotificationMinimumSeverity." ) if driver_level: if value is None: if DEBUG_ENABLED: config_kwargs["warn_notification_severity"] = ( NotificationMinimumSeverity.INFORMATION ) elif value == NotificationMinimumSeverity.OFF: config_kwargs["warn_notification_severity"] = None