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Edit File: connections.py
""" This module implements connections for MySQLdb. Presently there is only one class: Connection. Others are unlikely. However, you might want to make your own subclasses. In most cases, you will probably override Connection.default_cursor with a non-standard Cursor class. """ import re import sys from MySQLdb import cursors, _mysql from MySQLdb.compat import unicode, PY2 from MySQLdb._exceptions import ( Warning, Error, InterfaceError, DataError, DatabaseError, OperationalError, IntegrityError, InternalError, NotSupportedError, ProgrammingError, ) # Mapping from MySQL charset name to Python codec name _charset_to_encoding = { "utf8mb4": "utf8", "utf8mb3": "utf8", "latin1": "cp1252", "koi8r": "koi8_r", "koi8u": "koi8_u", } re_numeric_part = re.compile(r"^(\d+)") def numeric_part(s): """Returns the leading numeric part of a string. >>> numeric_part("20-alpha") 20 >>> numeric_part("foo") >>> numeric_part("16b") 16 """ m = re_numeric_part.match(s) if m: return int(m.group(1)) return None class Connection(_mysql.connection): """MySQL Database Connection Object""" default_cursor = cursors.Cursor def __init__(self, *args, **kwargs): """ Create a connection to the database. It is strongly recommended that you only use keyword parameters. Consult the MySQL C API documentation for more information. :param str host: host to connect :param str user: user to connect as :param str password: password to use :param str passwd: alias of password, for backward compatibility :param str database: database to use :param str db: alias of database, for backward compatibility :param int port: TCP/IP port to connect to :param str unix_socket: location of unix_socket to use :param dict conv: conversion dictionary, see MySQLdb.converters :param int connect_timeout: number of seconds to wait before the connection attempt fails. :param bool compress: if set, compression is enabled :param str named_pipe: if set, a named pipe is used to connect (Windows only) :param str init_command: command which is run once the connection is created :param str read_default_file: file from which default client values are read :param str read_default_group: configuration group to use from the default file :param type cursorclass: class object, used to create cursors (keyword only) :param bool use_unicode: If True, text-like columns are returned as unicode objects using the connection's character set. Otherwise, text-like columns are returned as bytes. Unicode objects will always be encoded to the connection's character set regardless of this setting. Default to False on Python 2 and True on Python 3 so that you can always get python `str` object by default. :param str charset: If supplied, the connection character set will be changed to this character set. On Python 2, this option changes default value of `use_unicode` option from False to True. :param str auth_plugin: If supplied, the connection default authentication plugin will be changed to this value. Example values: `mysql_native_password` or `caching_sha2_password` :param str sql_mode: If supplied, the session SQL mode will be changed to this setting. For more details and legal values, see the MySQL documentation. :param int client_flag: flags to use or 0 (see MySQL docs or constants/CLIENTS.py) :param dict ssl: dictionary or mapping contains SSL connection parameters; see the MySQL documentation for more details (mysql_ssl_set()). If this is set, and the client does not support SSL, NotSupportedError will be raised. :param bool local_infile: enables LOAD LOCAL INFILE; zero disables :param bool autocommit: If False (default), autocommit is disabled. If True, autocommit is enabled. If None, autocommit isn't set and server default is used. :param bool binary_prefix: If set, the '_binary' prefix will be used for raw byte query arguments (e.g. Binary). This is disabled by default. There are a number of undocumented, non-standard methods. See the documentation for the MySQL C API for some hints on what they do. """ from MySQLdb.constants import CLIENT, FIELD_TYPE from MySQLdb.converters import conversions, _bytes_or_str from weakref import proxy kwargs2 = kwargs.copy() if 'database' in kwargs2: kwargs2['db'] = kwargs2.pop('database') if 'password' in kwargs2: kwargs2['passwd'] = kwargs2.pop('password') if 'conv' in kwargs: conv = kwargs['conv'] else: conv = conversions conv2 = {} for k, v in conv.items(): if isinstance(k, int) and isinstance(v, list): conv2[k] = v[:] else: conv2[k] = v kwargs2['conv'] = conv2 cursorclass = kwargs2.pop('cursorclass', self.default_cursor) charset = kwargs2.get('charset', '') if charset or not PY2: use_unicode = True else: use_unicode = False use_unicode = kwargs2.pop('use_unicode', use_unicode) sql_mode = kwargs2.pop('sql_mode', '') self._binary_prefix = kwargs2.pop('binary_prefix', False) client_flag = kwargs.get('client_flag', 0) client_version = tuple([ numeric_part(n) for n in _mysql.get_client_info().split('.')[:2] ]) if client_version >= (4, 1): client_flag |= CLIENT.MULTI_STATEMENTS if client_version >= (5, 0): client_flag |= CLIENT.MULTI_RESULTS kwargs2['client_flag'] = client_flag # PEP-249 requires autocommit to be initially off autocommit = kwargs2.pop('autocommit', False) super(Connection, self).__init__(*args, **kwargs2) self.cursorclass = cursorclass self.encoders = dict([ (k, v) for k, v in conv.items() if type(k) is not int ]) # XXX THIS IS GARBAGE: While this is just a garbage and undocumented, # Django 1.11 depends on it. And they don't fix it because # they are in security-only fix mode. # So keep this garbage for now. This will be removed in 1.5. # See PyMySQL/mysqlclient-python#306 self.encoders[bytes] = bytes self._server_version = tuple([ numeric_part(n) for n in self.get_server_info().split('.')[:2] ]) self.encoding = 'ascii' # overridden in set_character_set() db = proxy(self) def unicode_literal(u, dummy=None): return db.string_literal(u.encode(db.encoding)) if not charset: charset = self.character_set_name() self.set_character_set(charset) if sql_mode: self.set_sql_mode(sql_mode) if use_unicode: for t in (FIELD_TYPE.STRING, FIELD_TYPE.VAR_STRING, FIELD_TYPE.VARCHAR, FIELD_TYPE.TINY_BLOB, FIELD_TYPE.MEDIUM_BLOB, FIELD_TYPE.LONG_BLOB, FIELD_TYPE.BLOB): self.converter[t] = _bytes_or_str # Unlike other string/blob types, JSON is always text. # MySQL may return JSON with charset==binary. self.converter[FIELD_TYPE.JSON] = unicode self.encoders[unicode] = unicode_literal self._transactional = self.server_capabilities & CLIENT.TRANSACTIONS if self._transactional: if autocommit is not None: self.autocommit(autocommit) self.messages = [] def autocommit(self, on): on = bool(on) if self.get_autocommit() != on: _mysql.connection.autocommit(self, on) def cursor(self, cursorclass=None): """ Create a cursor on which queries may be performed. The optional cursorclass parameter is used to create the Cursor. By default, self.cursorclass=cursors.Cursor is used. """ return (cursorclass or self.cursorclass)(self) def query(self, query): # Since _mysql releases GIL while querying, we need immutable buffer. if isinstance(query, bytearray): query = bytes(query) _mysql.connection.query(self, query) def _bytes_literal(self, bs): assert isinstance(bs, (bytes, bytearray)) x = self.string_literal(bs) # x is escaped and quoted bytes if self._binary_prefix: return b'_binary' + x return x def _tuple_literal(self, t): return b"(%s)" % (b','.join(map(self.literal, t))) def literal(self, o): """If o is a single object, returns an SQL literal as a string. If o is a non-string sequence, the items of the sequence are converted and returned as a sequence. Non-standard. For internal use; do not use this in your applications. """ if isinstance(o, unicode): s = self.string_literal(o.encode(self.encoding)) elif isinstance(o, bytearray): s = self._bytes_literal(o) elif isinstance(o, bytes): if PY2: s = self.string_literal(o) else: s = self._bytes_literal(o) elif isinstance(o, (tuple, list)): s = self._tuple_literal(o) else: s = self.escape(o, self.encoders) if isinstance(s, unicode): s = s.encode(self.encoding) assert isinstance(s, bytes) return s def begin(self): """Explicitly begin a connection. This method is not used when autocommit=False (default). """ self.query(b"BEGIN") if not hasattr(_mysql.connection, 'warning_count'): def warning_count(self): """Return the number of warnings generated from the last query. This is derived from the info() method.""" info = self.info() if info: return int(info.split()[-1]) else: return 0 def set_character_set(self, charset): """Set the connection character set to charset. The character set can only be changed in MySQL-4.1 and newer. If you try to change the character set from the current value in an older version, NotSupportedError will be raised.""" py_charset = _charset_to_encoding.get(charset, charset) if self.character_set_name() != charset: try: super(Connection, self).set_character_set(charset) except AttributeError: if self._server_version < (4, 1): raise NotSupportedError("server is too old to set charset") self.query('SET NAMES %s' % charset) self.store_result() self.encoding = py_charset def set_sql_mode(self, sql_mode): """Set the connection sql_mode. See MySQL documentation for legal values.""" if self._server_version < (4, 1): raise NotSupportedError("server is too old to set sql_mode") self.query("SET SESSION sql_mode='%s'" % sql_mode) self.store_result() def show_warnings(self): """Return detailed information about warnings as a sequence of tuples of (Level, Code, Message). This is only supported in MySQL-4.1 and up. If your server is an earlier version, an empty sequence is returned.""" if self._server_version < (4,1): return () self.query("SHOW WARNINGS") r = self.store_result() warnings = r.fetch_row(0) return warnings Warning = Warning Error = Error InterfaceError = InterfaceError DatabaseError = DatabaseError DataError = DataError OperationalError = OperationalError IntegrityError = IntegrityError InternalError = InternalError ProgrammingError = ProgrammingError NotSupportedError = NotSupportedError # vim: colorcolumn=100