ba-thesis/app/.venv/lib/python3.11/site-packages/psycopg/crdb/connection.py

186 lines
5.3 KiB
Python
Raw Normal View History

2023-07-21 09:57:46 +01:00
"""
CockroachDB-specific connections.
"""
# Copyright (C) 2022 The Psycopg Team
import re
from typing import Any, Optional, Type, Union, overload, TYPE_CHECKING
from .. import errors as e
from ..abc import AdaptContext
from ..rows import Row, RowFactory, AsyncRowFactory, TupleRow
from ..conninfo import ConnectionInfo
from ..connection import Connection
from .._adapters_map import AdaptersMap
from ..connection_async import AsyncConnection
from ._types import adapters
if TYPE_CHECKING:
from ..pq.abc import PGconn
from ..cursor import Cursor
from ..cursor_async import AsyncCursor
class _CrdbConnectionMixin:
_adapters: Optional[AdaptersMap]
pgconn: "PGconn"
@classmethod
def is_crdb(
cls, conn: Union[Connection[Any], AsyncConnection[Any], "PGconn"]
) -> bool:
"""
Return `!True` if the server connected to `!conn` is CockroachDB.
"""
if isinstance(conn, (Connection, AsyncConnection)):
conn = conn.pgconn
return bool(conn.parameter_status(b"crdb_version"))
@property
def adapters(self) -> AdaptersMap:
if not self._adapters:
# By default, use CockroachDB adapters map
self._adapters = AdaptersMap(adapters)
return self._adapters
@property
def info(self) -> "CrdbConnectionInfo":
return CrdbConnectionInfo(self.pgconn)
def _check_tpc(self) -> None:
if self.is_crdb(self.pgconn):
raise e.NotSupportedError("CockroachDB doesn't support prepared statements")
class CrdbConnection(_CrdbConnectionMixin, Connection[Row]):
"""
Wrapper for a connection to a CockroachDB database.
"""
__module__ = "psycopg.crdb"
# TODO: this method shouldn't require re-definition if the base class
# implements a generic self.
# https://github.com/psycopg/psycopg/issues/308
@overload
@classmethod
def connect(
cls,
conninfo: str = "",
*,
autocommit: bool = False,
row_factory: RowFactory[Row],
prepare_threshold: Optional[int] = 5,
cursor_factory: "Optional[Type[Cursor[Row]]]" = None,
context: Optional[AdaptContext] = None,
**kwargs: Union[None, int, str],
) -> "CrdbConnection[Row]":
...
@overload
@classmethod
def connect(
cls,
conninfo: str = "",
*,
autocommit: bool = False,
prepare_threshold: Optional[int] = 5,
cursor_factory: "Optional[Type[Cursor[Any]]]" = None,
context: Optional[AdaptContext] = None,
**kwargs: Union[None, int, str],
) -> "CrdbConnection[TupleRow]":
...
@classmethod
def connect(cls, conninfo: str = "", **kwargs: Any) -> "CrdbConnection[Any]":
"""
Connect to a database server and return a new `CrdbConnection` instance.
"""
return super().connect(conninfo, **kwargs) # type: ignore[return-value]
class AsyncCrdbConnection(_CrdbConnectionMixin, AsyncConnection[Row]):
"""
Wrapper for an async connection to a CockroachDB database.
"""
__module__ = "psycopg.crdb"
# TODO: this method shouldn't require re-definition if the base class
# implements a generic self.
# https://github.com/psycopg/psycopg/issues/308
@overload
@classmethod
async def connect(
cls,
conninfo: str = "",
*,
autocommit: bool = False,
prepare_threshold: Optional[int] = 5,
row_factory: AsyncRowFactory[Row],
cursor_factory: "Optional[Type[AsyncCursor[Row]]]" = None,
context: Optional[AdaptContext] = None,
**kwargs: Union[None, int, str],
) -> "AsyncCrdbConnection[Row]":
...
@overload
@classmethod
async def connect(
cls,
conninfo: str = "",
*,
autocommit: bool = False,
prepare_threshold: Optional[int] = 5,
cursor_factory: "Optional[Type[AsyncCursor[Any]]]" = None,
context: Optional[AdaptContext] = None,
**kwargs: Union[None, int, str],
) -> "AsyncCrdbConnection[TupleRow]":
...
@classmethod
async def connect(
cls, conninfo: str = "", **kwargs: Any
) -> "AsyncCrdbConnection[Any]":
return await super().connect(conninfo, **kwargs) # type: ignore [no-any-return]
class CrdbConnectionInfo(ConnectionInfo):
"""
`~psycopg.ConnectionInfo` subclass to get info about a CockroachDB database.
"""
__module__ = "psycopg.crdb"
@property
def vendor(self) -> str:
return "CockroachDB"
@property
def server_version(self) -> int:
"""
Return the CockroachDB server version connected.
Return a number in the PostgreSQL format (e.g. 21.2.10 -> 210210).
"""
sver = self.parameter_status("crdb_version")
if not sver:
raise e.InternalError("'crdb_version' parameter status not set")
ver = self.parse_crdb_version(sver)
if ver is None:
raise e.InterfaceError(f"couldn't parse CockroachDB version from: {sver!r}")
return ver
@classmethod
def parse_crdb_version(self, sver: str) -> Optional[int]:
m = re.search(r"\bv(\d+)\.(\d+)\.(\d+)", sver)
if not m:
return None
return int(m.group(1)) * 10000 + int(m.group(2)) * 100 + int(m.group(3))