"""Support for the MySQL database via the oursql adapter.
OurSQL is available at:
http://packages.python.org/oursql/
Connecting
-----------
Connect string format::
mysql+oursql://<user>:<password>@<host>[:<port>]/<dbname>
Character Sets
--------------
oursql defaults to using ``utf8`` as the connection charset, but other
encodings may be used instead. Like the MySQL-Python driver, unicode support
can be completely disabled::
# oursql sets the connection charset to utf8 automatically; all strings come
# back as utf8 str
create_engine('mysql+oursql:///mydb?use_unicode=0')
To not automatically use ``utf8`` and instead use whatever the connection
defaults to, there is a separate parameter::
# use the default connection charset; all strings come back as unicode
create_engine('mysql+oursql:///mydb?default_charset=1')
# use latin1 as the connection charset; all strings come back as unicode
create_engine('mysql+oursql:///mydb?charset=latin1')
"""
import re
from sqlalchemy.dialects.mysql.base import (BIT,MySQLDialect,MySQLExecutionContext
MySQLCompiler, MySQLIdentifierPreparer)
from sqlalchemy.engine import base
from sqlalchemy.sql import operators
from sqlalchemy import exc,log,schema,sql,types
from sqlalchemy import processors
class _oursqlBIT(BIT):
def result_processor(self, dialect, coltype):
"""oursql already converts mysql bits, so."""
return None
class MySQLExecutionContext_oursql(MySQLExecutionContext):
@property
def plain_query(self):
return self.execution_options.get('_oursql_plain_query', False)
class MySQLDialect_oursql(MySQLDialect):
driver = 'oursql'
# Py3K
# description_encoding = None
# Py2K
supports_unicode_binds = True
supports_unicode_statements = True
# end Py2K
supports_native_decimal = True
supports_sane_rowcount = True
supports_sane_multi_rowcount = True
execution_ctx_cls = MySQLExecutionContext_oursql
colspecs = util.update_copy(
MySQLDialect.colspecs,
{
sqltypes.Time: sqltypes.Time,
BIT: _oursqlBIT,
}
)
@classmethod
def dbapi(cls):
return __import__('oursql')
def do_execute(self, cursor, statement, parameters, context=None):
"""Provide an implementation of *cursor.execute(statement, parameters)*."""
if context and context.plain_query:
cursor.execute(statement, plain_query=True)
else:
cursor.execute(statement, parameters)
def do_begin(self, connection):
connection.cursor().execute('BEGIN', plain_query=True)
def _xa_query(self, connection, query, xid):
# Py2K
arg = connection.connection._escape_string(xid)
# end Py2K
# Py3K
# charset = self._connection_charset
# arg = connection.connection._escape_string(xid.encode(charset)).decode(charset)
connection.execution_options(_oursql_plain_query=True).execute(query % arg)
# Because mysql is bad, these methods have to be
# reimplemented to use _PlainQuery. Basically, some queries
# refuse to return any data if they're run through
# the parameterized query API, or refuse to be parameterized
# in the first place.
def do_begin_twophase(self, connection, xid):
self._xa_query(connection, 'XA BEGIN "%s"', xid)
def do_prepare_twophase(self, connection, xid):
self._xa_query(connection, 'XA END "%s"', xid)
self._xa_query(connection, 'XA PREPARE "%s"', xid)
def do_rollback_twophase(self, connection, xid, is_prepared=True,
recover=False):
if not is_prepared:
self._xa_query(connection, 'XA END "%s"', xid)
self._xa_query(connection, 'XA ROLLBACK "%s"', xid)
def do_commit_twophase(self, connection, xid, is_prepared=True,
recover=False):
if not is_prepared:
self.do_prepare_twophase(connection, xid)
self._xa_query(connection, 'XA COMMIT "%s"', xid)
# Q: why didn't we need all these "plain_query" overrides earlier ?
# am i on a newer/older version of OurSQL ?
def has_table(self, connection, table_name, schema=None):
return MySQLDialect.has_table(self,
connection.connect().\
execution_options(_oursql_plain_query=True),
table_name, schema)
def get_table_options(self, connection, table_name, schema=None, **kw):
return MySQLDialect.get_table_options(self,
connection.connect().\
execution_options(_oursql_plain_query=True),
table_name,
schema = schema,
**kw
)
def get_columns(self, connection, table_name, schema=None, **kw):
return MySQLDialect.get_columns(self,
connection.connect().\
execution_options(_oursql_plain_query=True),
table_name,
schema=schema,
**kw
)
def get_view_names(self, connection, schema=None, **kw):
return MySQLDialect.get_view_names(self,
connection.connect().\
execution_options(_oursql_plain_query=True),
schema=schema,
**kw
)
def get_table_names(self, connection, schema=None, **kw):
return MySQLDialect.get_table_names(self,
connection.connect().\
execution_options(_oursql_plain_query=True),
schema
)
def get_schema_names(self, connection, **kw):
return MySQLDialect.get_schema_names(self,
connection.connect().\
execution_options(_oursql_plain_query=True),
**kw
)
def initialize(self, connection):
return MySQLDialect.initialize(
self,
connection.execution_options(_oursql_plain_query=True)
)
def _show_create_table(self, connection, table, charset=None,
full_name=None):
return MySQLDialect._show_create_table(self,
connection.contextual_connect(close_with_result=True).
execution_options(_oursql_plain_query=True),
table, charset, full_name)
def is_disconnect(self, e):
if isinstance(e, self.dbapi.ProgrammingError):
return e.errno is None and 'cursor' not in e.args[1] and e.args[1].endswith('closed')
else:
return e.errno in (2006, 2013, 2014, 2045, 2055)
def create_connect_args(self, url):
opts = url.translate_connect_args(database='db', username='user',
password='passwd')
opts.update(url.query)
util.coerce_kw_type(opts, 'port', int)
util.coerce_kw_type(opts, 'compress', bool)
util.coerce_kw_type(opts, 'autoping', bool)
util.coerce_kw_type(opts, 'default_charset', bool)
if opts.pop('default_charset', False):
opts['charset'] = None
else:
util.coerce_kw_type(opts, 'charset', str)
opts['use_unicode'] = opts.get('use_unicode', True)
util.coerce_kw_type(opts, 'use_unicode', bool)
# FOUND_ROWS must be set in CLIENT_FLAGS to enable
# supports_sane_rowcount.
opts.setdefault('found_rows', True)
return [[], opts]
def _get_server_version_info(self, connection):
dbapi_con = connection.connection
version = []
r = re.compile('[.\-]')
for n in r.split(dbapi_con.server_info):
try:
version.append(int(n))
except ValueError:
version.append(n)
return tuple(version)
def _extract_error_code(self, exception):
try:
return exception.orig.errno
except AttributeError:
return None
def _detect_charset(self, connection):
"""Sniff out the character set in use for connection results."""
return connection.connection.charset
def _compat_fetchall(self, rp, charset=None):
"""oursql isn't super-broken like MySQLdb, yaaay."""
return rp.fetchall()
def _compat_fetchone(self, rp, charset=None):
"""oursql isn't super-broken like MySQLdb, yaaay."""
return rp.fetchone()
def _compat_first(self, rp, charset=None):
return rp.first()
dialect = MySQLDialect_oursql
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