447 lines
14 KiB
Python
447 lines
14 KiB
Python
# dialects/sqlite/aiosqlite.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
|
|
|
|
|
|
r"""
|
|
|
|
.. dialect:: sqlite+aiosqlite
|
|
:name: aiosqlite
|
|
:dbapi: aiosqlite
|
|
:connectstring: sqlite+aiosqlite:///file_path
|
|
:url: https://pypi.org/project/aiosqlite/
|
|
|
|
The aiosqlite dialect provides support for the SQLAlchemy asyncio interface
|
|
running on top of pysqlite.
|
|
|
|
aiosqlite is a wrapper around pysqlite that uses a background thread for
|
|
each connection. It does not actually use non-blocking IO, as SQLite
|
|
databases are not socket-based. However it does provide a working asyncio
|
|
interface that's useful for testing and prototyping purposes.
|
|
|
|
Using a special asyncio mediation layer, the aiosqlite dialect is usable
|
|
as the backend for the :ref:`SQLAlchemy asyncio <asyncio_toplevel>`
|
|
extension package.
|
|
|
|
This dialect should normally be used only with the
|
|
:func:`_asyncio.create_async_engine` engine creation function::
|
|
|
|
from sqlalchemy.ext.asyncio import create_async_engine
|
|
|
|
engine = create_async_engine("sqlite+aiosqlite:///filename")
|
|
|
|
The URL passes through all arguments to the ``pysqlite`` driver, so all
|
|
connection arguments are the same as they are for that of :ref:`pysqlite`.
|
|
|
|
.. _aiosqlite_udfs:
|
|
|
|
User-Defined Functions
|
|
----------------------
|
|
|
|
aiosqlite extends pysqlite to support async, so we can create our own user-defined functions (UDFs)
|
|
in Python and use them directly in SQLite queries as described here: :ref:`pysqlite_udfs`.
|
|
|
|
.. _aiosqlite_serializable:
|
|
|
|
Serializable isolation / Savepoints / Transactional DDL (asyncio version)
|
|
-------------------------------------------------------------------------
|
|
|
|
A newly revised version of this important section is now available
|
|
at the top level of the SQLAlchemy SQLite documentation, in the section
|
|
:ref:`sqlite_transactions`.
|
|
|
|
|
|
.. _aiosqlite_pooling:
|
|
|
|
Pooling Behavior
|
|
----------------
|
|
|
|
The SQLAlchemy ``aiosqlite`` DBAPI establishes the connection pool differently
|
|
based on the kind of SQLite database that's requested:
|
|
|
|
* When a ``:memory:`` SQLite database is specified, the dialect by default
|
|
will use :class:`.StaticPool`. This pool maintains a single
|
|
connection, so that all access to the engine
|
|
use the same ``:memory:`` database.
|
|
* When a file-based database is specified, the dialect will use
|
|
:class:`.AsyncAdaptedQueuePool` as the source of connections.
|
|
|
|
.. versionchanged:: 2.0.38
|
|
|
|
SQLite file database engines now use :class:`.AsyncAdaptedQueuePool` by default.
|
|
Previously, :class:`.NullPool` were used. The :class:`.NullPool` class
|
|
may be used by specifying it via the
|
|
:paramref:`_sa.create_engine.poolclass` parameter.
|
|
|
|
""" # noqa
|
|
from __future__ import annotations
|
|
|
|
import asyncio
|
|
from collections import deque
|
|
from functools import partial
|
|
from types import ModuleType
|
|
from typing import Any
|
|
from typing import cast
|
|
from typing import Deque
|
|
from typing import Iterator
|
|
from typing import NoReturn
|
|
from typing import Optional
|
|
from typing import Sequence
|
|
from typing import TYPE_CHECKING
|
|
from typing import Union
|
|
|
|
from .base import SQLiteExecutionContext
|
|
from .pysqlite import SQLiteDialect_pysqlite
|
|
from ... import pool
|
|
from ... import util
|
|
from ...connectors.asyncio import AsyncAdapt_dbapi_module
|
|
from ...engine import AdaptedConnection
|
|
from ...util.concurrency import await_fallback
|
|
from ...util.concurrency import await_only
|
|
|
|
if TYPE_CHECKING:
|
|
from ...connectors.asyncio import AsyncIODBAPIConnection
|
|
from ...connectors.asyncio import AsyncIODBAPICursor
|
|
from ...engine.interfaces import _DBAPICursorDescription
|
|
from ...engine.interfaces import _DBAPIMultiExecuteParams
|
|
from ...engine.interfaces import _DBAPISingleExecuteParams
|
|
from ...engine.interfaces import DBAPIConnection
|
|
from ...engine.interfaces import DBAPICursor
|
|
from ...engine.interfaces import DBAPIModule
|
|
from ...engine.url import URL
|
|
from ...pool.base import PoolProxiedConnection
|
|
|
|
|
|
class AsyncAdapt_aiosqlite_cursor:
|
|
# TODO: base on connectors/asyncio.py
|
|
# see #10415
|
|
|
|
__slots__ = (
|
|
"_adapt_connection",
|
|
"_connection",
|
|
"description",
|
|
"await_",
|
|
"_rows",
|
|
"arraysize",
|
|
"rowcount",
|
|
"lastrowid",
|
|
)
|
|
|
|
server_side = False
|
|
|
|
def __init__(self, adapt_connection: AsyncAdapt_aiosqlite_connection):
|
|
self._adapt_connection = adapt_connection
|
|
self._connection = adapt_connection._connection
|
|
self.await_ = adapt_connection.await_
|
|
self.arraysize = 1
|
|
self.rowcount = -1
|
|
self.description: Optional[_DBAPICursorDescription] = None
|
|
self._rows: Deque[Any] = deque()
|
|
|
|
async def _async_soft_close(self) -> None:
|
|
return
|
|
|
|
def close(self) -> None:
|
|
self._rows.clear()
|
|
|
|
def execute(
|
|
self,
|
|
operation: Any,
|
|
parameters: Optional[_DBAPISingleExecuteParams] = None,
|
|
) -> Any:
|
|
|
|
try:
|
|
_cursor: AsyncIODBAPICursor = self.await_(self._connection.cursor()) # type: ignore[arg-type] # noqa: E501
|
|
|
|
if parameters is None:
|
|
self.await_(_cursor.execute(operation))
|
|
else:
|
|
self.await_(_cursor.execute(operation, parameters))
|
|
|
|
if _cursor.description:
|
|
self.description = _cursor.description
|
|
self.lastrowid = self.rowcount = -1
|
|
|
|
if not self.server_side:
|
|
self._rows = deque(self.await_(_cursor.fetchall()))
|
|
else:
|
|
self.description = None
|
|
self.lastrowid = _cursor.lastrowid
|
|
self.rowcount = _cursor.rowcount
|
|
|
|
if not self.server_side:
|
|
self.await_(_cursor.close())
|
|
else:
|
|
self._cursor = _cursor # type: ignore[misc]
|
|
except Exception as error:
|
|
self._adapt_connection._handle_exception(error)
|
|
|
|
def executemany(
|
|
self,
|
|
operation: Any,
|
|
seq_of_parameters: _DBAPIMultiExecuteParams,
|
|
) -> Any:
|
|
try:
|
|
_cursor: AsyncIODBAPICursor = self.await_(self._connection.cursor()) # type: ignore[arg-type] # noqa: E501
|
|
self.await_(_cursor.executemany(operation, seq_of_parameters))
|
|
self.description = None
|
|
self.lastrowid = _cursor.lastrowid
|
|
self.rowcount = _cursor.rowcount
|
|
self.await_(_cursor.close())
|
|
except Exception as error:
|
|
self._adapt_connection._handle_exception(error)
|
|
|
|
def setinputsizes(self, *inputsizes: Any) -> None:
|
|
pass
|
|
|
|
def __iter__(self) -> Iterator[Any]:
|
|
while self._rows:
|
|
yield self._rows.popleft()
|
|
|
|
def fetchone(self) -> Optional[Any]:
|
|
if self._rows:
|
|
return self._rows.popleft()
|
|
else:
|
|
return None
|
|
|
|
def fetchmany(self, size: Optional[int] = None) -> Sequence[Any]:
|
|
if size is None:
|
|
size = self.arraysize
|
|
|
|
rr = self._rows
|
|
return [rr.popleft() for _ in range(min(size, len(rr)))]
|
|
|
|
def fetchall(self) -> Sequence[Any]:
|
|
retval = list(self._rows)
|
|
self._rows.clear()
|
|
return retval
|
|
|
|
|
|
class AsyncAdapt_aiosqlite_ss_cursor(AsyncAdapt_aiosqlite_cursor):
|
|
# TODO: base on connectors/asyncio.py
|
|
# see #10415
|
|
__slots__ = "_cursor"
|
|
|
|
server_side = True
|
|
|
|
def __init__(self, *arg: Any, **kw: Any) -> None:
|
|
super().__init__(*arg, **kw)
|
|
self._cursor: Optional[AsyncIODBAPICursor] = None
|
|
|
|
def close(self) -> None:
|
|
if self._cursor is not None:
|
|
self.await_(self._cursor.close())
|
|
self._cursor = None
|
|
|
|
def fetchone(self) -> Optional[Any]:
|
|
assert self._cursor is not None
|
|
return self.await_(self._cursor.fetchone())
|
|
|
|
def fetchmany(self, size: Optional[int] = None) -> Sequence[Any]:
|
|
assert self._cursor is not None
|
|
if size is None:
|
|
size = self.arraysize
|
|
return self.await_(self._cursor.fetchmany(size=size))
|
|
|
|
def fetchall(self) -> Sequence[Any]:
|
|
assert self._cursor is not None
|
|
return self.await_(self._cursor.fetchall())
|
|
|
|
|
|
class AsyncAdapt_aiosqlite_connection(AdaptedConnection):
|
|
await_ = staticmethod(await_only)
|
|
__slots__ = ("dbapi",)
|
|
|
|
def __init__(self, dbapi: Any, connection: AsyncIODBAPIConnection) -> None:
|
|
self.dbapi = dbapi
|
|
self._connection = connection
|
|
|
|
@property
|
|
def isolation_level(self) -> Optional[str]:
|
|
return cast(str, self._connection.isolation_level)
|
|
|
|
@isolation_level.setter
|
|
def isolation_level(self, value: Optional[str]) -> None:
|
|
# aiosqlite's isolation_level setter works outside the Thread
|
|
# that it's supposed to, necessitating setting check_same_thread=False.
|
|
# for improved stability, we instead invent our own awaitable version
|
|
# using aiosqlite's async queue directly.
|
|
|
|
def set_iso(
|
|
connection: AsyncAdapt_aiosqlite_connection, value: Optional[str]
|
|
) -> None:
|
|
connection.isolation_level = value
|
|
|
|
function = partial(set_iso, self._connection._conn, value)
|
|
future = asyncio.get_event_loop().create_future()
|
|
|
|
self._connection._tx.put_nowait((future, function))
|
|
|
|
try:
|
|
self.await_(future)
|
|
except Exception as error:
|
|
self._handle_exception(error)
|
|
|
|
def create_function(self, *args: Any, **kw: Any) -> None:
|
|
try:
|
|
self.await_(self._connection.create_function(*args, **kw))
|
|
except Exception as error:
|
|
self._handle_exception(error)
|
|
|
|
def cursor(self, server_side: bool = False) -> AsyncAdapt_aiosqlite_cursor:
|
|
if server_side:
|
|
return AsyncAdapt_aiosqlite_ss_cursor(self)
|
|
else:
|
|
return AsyncAdapt_aiosqlite_cursor(self)
|
|
|
|
def execute(self, *args: Any, **kw: Any) -> Any:
|
|
return self.await_(self._connection.execute(*args, **kw))
|
|
|
|
def rollback(self) -> None:
|
|
try:
|
|
self.await_(self._connection.rollback())
|
|
except Exception as error:
|
|
self._handle_exception(error)
|
|
|
|
def commit(self) -> None:
|
|
try:
|
|
self.await_(self._connection.commit())
|
|
except Exception as error:
|
|
self._handle_exception(error)
|
|
|
|
def close(self) -> None:
|
|
try:
|
|
self.await_(self._connection.close())
|
|
except ValueError:
|
|
# this is undocumented for aiosqlite, that ValueError
|
|
# was raised if .close() was called more than once, which is
|
|
# both not customary for DBAPI and is also not a DBAPI.Error
|
|
# exception. This is now fixed in aiosqlite via my PR
|
|
# https://github.com/omnilib/aiosqlite/pull/238, so we can be
|
|
# assured this will not become some other kind of exception,
|
|
# since it doesn't raise anymore.
|
|
|
|
pass
|
|
except Exception as error:
|
|
self._handle_exception(error)
|
|
|
|
def _handle_exception(self, error: Exception) -> NoReturn:
|
|
if (
|
|
isinstance(error, ValueError)
|
|
and error.args[0] == "no active connection"
|
|
):
|
|
raise self.dbapi.sqlite.OperationalError(
|
|
"no active connection"
|
|
) from error
|
|
else:
|
|
raise error
|
|
|
|
|
|
class AsyncAdaptFallback_aiosqlite_connection(AsyncAdapt_aiosqlite_connection):
|
|
__slots__ = ()
|
|
|
|
await_ = staticmethod(await_fallback)
|
|
|
|
|
|
class AsyncAdapt_aiosqlite_dbapi(AsyncAdapt_dbapi_module):
|
|
def __init__(self, aiosqlite: ModuleType, sqlite: ModuleType):
|
|
self.aiosqlite = aiosqlite
|
|
self.sqlite = sqlite
|
|
self.paramstyle = "qmark"
|
|
self._init_dbapi_attributes()
|
|
|
|
def _init_dbapi_attributes(self) -> None:
|
|
for name in (
|
|
"DatabaseError",
|
|
"Error",
|
|
"IntegrityError",
|
|
"NotSupportedError",
|
|
"OperationalError",
|
|
"ProgrammingError",
|
|
"sqlite_version",
|
|
"sqlite_version_info",
|
|
):
|
|
setattr(self, name, getattr(self.aiosqlite, name))
|
|
|
|
for name in ("PARSE_COLNAMES", "PARSE_DECLTYPES"):
|
|
setattr(self, name, getattr(self.sqlite, name))
|
|
|
|
for name in ("Binary",):
|
|
setattr(self, name, getattr(self.sqlite, name))
|
|
|
|
def connect(self, *arg: Any, **kw: Any) -> AsyncAdapt_aiosqlite_connection:
|
|
async_fallback = kw.pop("async_fallback", False)
|
|
|
|
creator_fn = kw.pop("async_creator_fn", None)
|
|
if creator_fn:
|
|
connection = creator_fn(*arg, **kw)
|
|
else:
|
|
connection = self.aiosqlite.connect(*arg, **kw)
|
|
# it's a Thread. you'll thank us later
|
|
connection.daemon = True
|
|
|
|
if util.asbool(async_fallback):
|
|
return AsyncAdaptFallback_aiosqlite_connection(
|
|
self,
|
|
await_fallback(connection),
|
|
)
|
|
else:
|
|
return AsyncAdapt_aiosqlite_connection(
|
|
self,
|
|
await_only(connection),
|
|
)
|
|
|
|
|
|
class SQLiteExecutionContext_aiosqlite(SQLiteExecutionContext):
|
|
def create_server_side_cursor(self) -> DBAPICursor:
|
|
return self._dbapi_connection.cursor(server_side=True)
|
|
|
|
|
|
class SQLiteDialect_aiosqlite(SQLiteDialect_pysqlite):
|
|
driver = "aiosqlite"
|
|
supports_statement_cache = True
|
|
|
|
is_async = True
|
|
|
|
supports_server_side_cursors = True
|
|
|
|
execution_ctx_cls = SQLiteExecutionContext_aiosqlite
|
|
|
|
@classmethod
|
|
def import_dbapi(cls) -> AsyncAdapt_aiosqlite_dbapi:
|
|
return AsyncAdapt_aiosqlite_dbapi(
|
|
__import__("aiosqlite"), __import__("sqlite3")
|
|
)
|
|
|
|
@classmethod
|
|
def get_pool_class(cls, url: URL) -> type[pool.Pool]:
|
|
if cls._is_url_file_db(url):
|
|
return pool.AsyncAdaptedQueuePool
|
|
else:
|
|
return pool.StaticPool
|
|
|
|
def is_disconnect(
|
|
self,
|
|
e: DBAPIModule.Error,
|
|
connection: Optional[Union[PoolProxiedConnection, DBAPIConnection]],
|
|
cursor: Optional[DBAPICursor],
|
|
) -> bool:
|
|
self.dbapi = cast("DBAPIModule", self.dbapi)
|
|
if isinstance(
|
|
e, self.dbapi.OperationalError
|
|
) and "no active connection" in str(e):
|
|
return True
|
|
|
|
return super().is_disconnect(e, connection, cursor)
|
|
|
|
def get_driver_connection(
|
|
self, connection: DBAPIConnection
|
|
) -> AsyncIODBAPIConnection:
|
|
return connection._connection # type: ignore[no-any-return]
|
|
|
|
|
|
dialect = SQLiteDialect_aiosqlite
|