You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
150 lines
5.2 KiB
Python
150 lines
5.2 KiB
Python
# connectors/mxodbc.py
|
|
# Copyright (C) 2005-2013 the SQLAlchemy authors and contributors <see AUTHORS file>
|
|
#
|
|
# This module is part of SQLAlchemy and is released under
|
|
# the MIT License: http://www.opensource.org/licenses/mit-license.php
|
|
|
|
"""
|
|
Provide an SQLALchemy connector for the eGenix mxODBC commercial
|
|
Python adapter for ODBC. This is not a free product, but eGenix
|
|
provides SQLAlchemy with a license for use in continuous integration
|
|
testing.
|
|
|
|
This has been tested for use with mxODBC 3.1.2 on SQL Server 2005
|
|
and 2008, using the SQL Server Native driver. However, it is
|
|
possible for this to be used on other database platforms.
|
|
|
|
For more info on mxODBC, see http://www.egenix.com/
|
|
|
|
"""
|
|
|
|
import sys
|
|
import re
|
|
import warnings
|
|
|
|
from . import Connector
|
|
|
|
|
|
class MxODBCConnector(Connector):
|
|
driver = 'mxodbc'
|
|
|
|
supports_sane_multi_rowcount = False
|
|
supports_unicode_statements = True
|
|
supports_unicode_binds = True
|
|
|
|
supports_native_decimal = True
|
|
|
|
@classmethod
|
|
def dbapi(cls):
|
|
# this classmethod will normally be replaced by an instance
|
|
# attribute of the same name, so this is normally only called once.
|
|
cls._load_mx_exceptions()
|
|
platform = sys.platform
|
|
if platform == 'win32':
|
|
from mx.ODBC import Windows as module
|
|
# this can be the string "linux2", and possibly others
|
|
elif 'linux' in platform:
|
|
from mx.ODBC import unixODBC as module
|
|
elif platform == 'darwin':
|
|
from mx.ODBC import iODBC as module
|
|
else:
|
|
raise ImportError("Unrecognized platform for mxODBC import")
|
|
return module
|
|
|
|
@classmethod
|
|
def _load_mx_exceptions(cls):
|
|
""" Import mxODBC exception classes into the module namespace,
|
|
as if they had been imported normally. This is done here
|
|
to avoid requiring all SQLAlchemy users to install mxODBC.
|
|
"""
|
|
global InterfaceError, ProgrammingError
|
|
from mx.ODBC import InterfaceError
|
|
from mx.ODBC import ProgrammingError
|
|
|
|
def on_connect(self):
|
|
def connect(conn):
|
|
conn.stringformat = self.dbapi.MIXED_STRINGFORMAT
|
|
conn.datetimeformat = self.dbapi.PYDATETIME_DATETIMEFORMAT
|
|
conn.decimalformat = self.dbapi.DECIMAL_DECIMALFORMAT
|
|
conn.errorhandler = self._error_handler()
|
|
return connect
|
|
|
|
def _error_handler(self):
|
|
""" Return a handler that adjusts mxODBC's raised Warnings to
|
|
emit Python standard warnings.
|
|
"""
|
|
from mx.ODBC.Error import Warning as MxOdbcWarning
|
|
|
|
def error_handler(connection, cursor, errorclass, errorvalue):
|
|
if issubclass(errorclass, MxOdbcWarning):
|
|
errorclass.__bases__ = (Warning,)
|
|
warnings.warn(message=str(errorvalue),
|
|
category=errorclass,
|
|
stacklevel=2)
|
|
else:
|
|
raise errorclass, errorvalue
|
|
return error_handler
|
|
|
|
def create_connect_args(self, url):
|
|
""" Return a tuple of *args,**kwargs for creating a connection.
|
|
|
|
The mxODBC 3.x connection constructor looks like this:
|
|
|
|
connect(dsn, user='', password='',
|
|
clear_auto_commit=1, errorhandler=None)
|
|
|
|
This method translates the values in the provided uri
|
|
into args and kwargs needed to instantiate an mxODBC Connection.
|
|
|
|
The arg 'errorhandler' is not used by SQLAlchemy and will
|
|
not be populated.
|
|
|
|
"""
|
|
opts = url.translate_connect_args(username='user')
|
|
opts.update(url.query)
|
|
args = opts.pop('host')
|
|
opts.pop('port', None)
|
|
opts.pop('database', None)
|
|
return (args,), opts
|
|
|
|
def is_disconnect(self, e, connection, cursor):
|
|
# TODO: eGenix recommends checking connection.closed here
|
|
# Does that detect dropped connections ?
|
|
if isinstance(e, self.dbapi.ProgrammingError):
|
|
return "connection already closed" in str(e)
|
|
elif isinstance(e, self.dbapi.Error):
|
|
return '[08S01]' in str(e)
|
|
else:
|
|
return False
|
|
|
|
def _get_server_version_info(self, connection):
|
|
# eGenix suggests using conn.dbms_version instead
|
|
# of what we're doing here
|
|
dbapi_con = connection.connection
|
|
version = []
|
|
r = re.compile('[.\-]')
|
|
# 18 == pyodbc.SQL_DBMS_VER
|
|
for n in r.split(dbapi_con.getinfo(18)[1]):
|
|
try:
|
|
version.append(int(n))
|
|
except ValueError:
|
|
version.append(n)
|
|
return tuple(version)
|
|
|
|
def _get_direct(self, context):
|
|
if context:
|
|
native_odbc_execute = context.execution_options.\
|
|
get('native_odbc_execute', 'auto')
|
|
# default to direct=True in all cases, is more generally
|
|
# compatible especially with SQL Server
|
|
return False if native_odbc_execute is True else True
|
|
else:
|
|
return True
|
|
|
|
def do_executemany(self, cursor, statement, parameters, context=None):
|
|
cursor.executemany(
|
|
statement, parameters, direct=self._get_direct(context))
|
|
|
|
def do_execute(self, cursor, statement, parameters, context=None):
|
|
cursor.execute(statement, parameters, direct=self._get_direct(context))
|