university-final-iot-backend/env/lib/python3.6/site-packages/sqlalchemy/connectors/pyodbc.py

165 lines
5.5 KiB
Python

# connectors/pyodbc.py
# Copyright (C) 2005-2018 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
from . import Connector
from .. import util
import re
class PyODBCConnector(Connector):
driver = 'pyodbc'
supports_sane_rowcount_returning = False
supports_sane_multi_rowcount = False
supports_unicode_statements = True
supports_unicode_binds = True
supports_native_decimal = True
default_paramstyle = 'named'
# for non-DSN connections, this *may* be used to
# hold the desired driver name
pyodbc_driver_name = None
def __init__(self, supports_unicode_binds=None, **kw):
super(PyODBCConnector, self).__init__(**kw)
if supports_unicode_binds is not None:
self.supports_unicode_binds = supports_unicode_binds
@classmethod
def dbapi(cls):
return __import__('pyodbc')
def create_connect_args(self, url):
opts = url.translate_connect_args(username='user')
opts.update(url.query)
keys = opts
query = url.query
connect_args = {}
for param in ('ansi', 'unicode_results', 'autocommit'):
if param in keys:
connect_args[param] = util.asbool(keys.pop(param))
if 'odbc_connect' in keys:
connectors = [util.unquote_plus(keys.pop('odbc_connect'))]
else:
def check_quote(token):
if ";" in str(token):
token = "'%s'" % token
return token
keys = dict(
(k, check_quote(v)) for k, v in keys.items()
)
dsn_connection = 'dsn' in keys or \
('host' in keys and 'database' not in keys)
if dsn_connection:
connectors = ['dsn=%s' % (keys.pop('host', '') or
keys.pop('dsn', ''))]
else:
port = ''
if 'port' in keys and 'port' not in query:
port = ',%d' % int(keys.pop('port'))
connectors = []
driver = keys.pop('driver', self.pyodbc_driver_name)
if driver is None:
util.warn(
"No driver name specified; "
"this is expected by PyODBC when using "
"DSN-less connections")
else:
connectors.append("DRIVER={%s}" % driver)
connectors.extend(
[
'Server=%s%s' % (keys.pop('host', ''), port),
'Database=%s' % keys.pop('database', '')
])
user = keys.pop("user", None)
if user:
connectors.append("UID=%s" % user)
connectors.append("PWD=%s" % keys.pop('password', ''))
else:
connectors.append("Trusted_Connection=Yes")
# if set to 'Yes', the ODBC layer will try to automagically
# convert textual data from your database encoding to your
# client encoding. This should obviously be set to 'No' if
# you query a cp1253 encoded database from a latin1 client...
if 'odbc_autotranslate' in keys:
connectors.append("AutoTranslate=%s" %
keys.pop("odbc_autotranslate"))
connectors.extend(['%s=%s' % (k, v) for k, v in keys.items()])
return [[";".join(connectors)], connect_args]
def is_disconnect(self, e, connection, cursor):
if isinstance(e, self.dbapi.ProgrammingError):
return "The cursor's connection has been closed." in str(e) or \
'Attempt to use a closed connection.' in str(e)
else:
return False
# def initialize(self, connection):
# super(PyODBCConnector, self).initialize(connection)
def _dbapi_version(self):
if not self.dbapi:
return ()
return self._parse_dbapi_version(self.dbapi.version)
def _parse_dbapi_version(self, vers):
m = re.match(
r'(?:py.*-)?([\d\.]+)(?:-(\w+))?',
vers
)
if not m:
return ()
vers = tuple([int(x) for x in m.group(1).split(".")])
if m.group(2):
vers += (m.group(2),)
return vers
def _get_server_version_info(self, connection, allow_chars=True):
# NOTE: this function is not reliable, particularly when
# freetds is in use. Implement database-specific server version
# queries.
dbapi_con = connection.connection
version = []
r = re.compile(r'[.\-]')
for n in r.split(dbapi_con.getinfo(self.dbapi.SQL_DBMS_VER)):
try:
version.append(int(n))
except ValueError:
if allow_chars:
version.append(n)
return tuple(version)
def set_isolation_level(self, connection, level):
# adjust for ConnectionFairy being present
# allows attribute set e.g. "connection.autocommit = True"
# to work properly
if hasattr(connection, 'connection'):
connection = connection.connection
if level == 'AUTOCOMMIT':
connection.autocommit = True
else:
connection.autocommit = False
super(PyODBCConnector, self).set_isolation_level(connection,
level)