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author | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
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committer | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
commit | 4a52a71956a8d46fcb7294ac71734504bb09bcc2 (patch) | |
tree | ee3dc5af3b6313e921cd920906356f5d4febc4ed /.venv/lib/python3.12/site-packages/sqlalchemy/engine/characteristics.py | |
parent | cc961e04ba734dd72309fb548a2f97d67d578813 (diff) | |
download | gn-ai-master.tar.gz |
Diffstat (limited to '.venv/lib/python3.12/site-packages/sqlalchemy/engine/characteristics.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/sqlalchemy/engine/characteristics.py | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/sqlalchemy/engine/characteristics.py b/.venv/lib/python3.12/site-packages/sqlalchemy/engine/characteristics.py new file mode 100644 index 00000000..322c28b5 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/sqlalchemy/engine/characteristics.py @@ -0,0 +1,155 @@ +# engine/characteristics.py +# Copyright (C) 2005-2025 the SQLAlchemy authors and contributors +# <see AUTHORS file> +# +# This module is part of SQLAlchemy and is released under +# the MIT License: https://www.opensource.org/licenses/mit-license.php +from __future__ import annotations + +import abc +import typing +from typing import Any +from typing import ClassVar + +if typing.TYPE_CHECKING: + from .base import Connection + from .interfaces import DBAPIConnection + from .interfaces import Dialect + + +class ConnectionCharacteristic(abc.ABC): + """An abstract base for an object that can set, get and reset a + per-connection characteristic, typically one that gets reset when the + connection is returned to the connection pool. + + transaction isolation is the canonical example, and the + ``IsolationLevelCharacteristic`` implementation provides this for the + ``DefaultDialect``. + + The ``ConnectionCharacteristic`` class should call upon the ``Dialect`` for + the implementation of each method. The object exists strictly to serve as + a dialect visitor that can be placed into the + ``DefaultDialect.connection_characteristics`` dictionary where it will take + effect for calls to :meth:`_engine.Connection.execution_options` and + related APIs. + + .. versionadded:: 1.4 + + """ + + __slots__ = () + + transactional: ClassVar[bool] = False + + @abc.abstractmethod + def reset_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection + ) -> None: + """Reset the characteristic on the DBAPI connection to its default + value.""" + + @abc.abstractmethod + def set_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection, value: Any + ) -> None: + """set characteristic on the DBAPI connection to a given value.""" + + def set_connection_characteristic( + self, + dialect: Dialect, + conn: Connection, + dbapi_conn: DBAPIConnection, + value: Any, + ) -> None: + """set characteristic on the :class:`_engine.Connection` to a given + value. + + .. versionadded:: 2.0.30 - added to support elements that are local + to the :class:`_engine.Connection` itself. + + """ + self.set_characteristic(dialect, dbapi_conn, value) + + @abc.abstractmethod + def get_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection + ) -> Any: + """Given a DBAPI connection, get the current value of the + characteristic. + + """ + + def get_connection_characteristic( + self, dialect: Dialect, conn: Connection, dbapi_conn: DBAPIConnection + ) -> Any: + """Given a :class:`_engine.Connection`, get the current value of the + characteristic. + + .. versionadded:: 2.0.30 - added to support elements that are local + to the :class:`_engine.Connection` itself. + + """ + return self.get_characteristic(dialect, dbapi_conn) + + +class IsolationLevelCharacteristic(ConnectionCharacteristic): + """Manage the isolation level on a DBAPI connection""" + + transactional: ClassVar[bool] = True + + def reset_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection + ) -> None: + dialect.reset_isolation_level(dbapi_conn) + + def set_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection, value: Any + ) -> None: + dialect._assert_and_set_isolation_level(dbapi_conn, value) + + def get_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection + ) -> Any: + return dialect.get_isolation_level(dbapi_conn) + + +class LoggingTokenCharacteristic(ConnectionCharacteristic): + """Manage the 'logging_token' option of a :class:`_engine.Connection`. + + .. versionadded:: 2.0.30 + + """ + + transactional: ClassVar[bool] = False + + def reset_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection + ) -> None: + pass + + def set_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection, value: Any + ) -> None: + raise NotImplementedError() + + def set_connection_characteristic( + self, + dialect: Dialect, + conn: Connection, + dbapi_conn: DBAPIConnection, + value: Any, + ) -> None: + if value: + conn._message_formatter = lambda msg: "[%s] %s" % (value, msg) + else: + del conn._message_formatter + + def get_characteristic( + self, dialect: Dialect, dbapi_conn: DBAPIConnection + ) -> Any: + raise NotImplementedError() + + def get_connection_characteristic( + self, dialect: Dialect, conn: Connection, dbapi_conn: DBAPIConnection + ) -> Any: + return conn._execution_options.get("logging_token", None) |