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- # connectors/pyodbc.py
- # Copyright (C) 2005-2021 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
-
- import re
-
- from . import Connector
- from .. import util
-
-
- class PyODBCConnector(Connector):
- driver = "pyodbc"
-
- # this is no longer False for pyodbc in general
- supports_sane_rowcount_returning = True
- supports_sane_multi_rowcount = False
-
- supports_unicode_statements = True
- supports_unicode_binds = True
-
- supports_native_decimal = True
- default_paramstyle = "named"
-
- use_setinputsizes = False
-
- # 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, use_setinputsizes=False, **kw
- ):
- super(PyODBCConnector, self).__init__(**kw)
- if supports_unicode_binds is not None:
- self.supports_unicode_binds = supports_unicode_binds
- self.use_setinputsizes = use_setinputsizes
-
- @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.replace("}", "}}")
- 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 and keys:
- # note if keys is empty, this is a totally blank URL
- 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)
- pwd = keys.pop("password", "")
- if pwd:
- connectors.append("PWD=%s" % pwd)
- else:
- authentication = keys.pop("authentication", None)
- if authentication:
- connectors.append("Authentication=%s" % authentication)
- 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 _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 do_set_input_sizes(self, cursor, list_of_tuples, context):
- # the rules for these types seems a little strange, as you can pass
- # non-tuples as well as tuples, however it seems to assume "0"
- # for the subsequent values if you don't pass a tuple which fails
- # for types such as pyodbc.SQL_WLONGVARCHAR, which is the datatype
- # that ticket #5649 is targeting.
-
- # NOTE: as of #6058, this won't be called if the use_setinputsizes flag
- # is False, or if no types were specified in list_of_tuples
-
- cursor.setinputsizes(
- [
- (dbtype, None, None)
- if not isinstance(dbtype, tuple)
- else dbtype
- for key, dbtype, sqltype in list_of_tuples
- ]
- )
-
- 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)
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