# Source code for sqlobject.mysql.mysqlconnection

    from sqlobject import col, dberrors
    from sqlobject.compat import PY2
    from sqlobject.dbconnection import DBAPI

    class ErrorMessage(str):
        def __new__(cls, e, append_msg=''):
            if len(e.args) > 1:
                obj = str.__new__(cls, e.args[1] + append_msg)
            else:
                obj = str.__new__(cls, append_msg)
            try:
                obj.code = int(e.args[0])
            except ValueError:
                obj.code = e.args[0]
            obj.module = e.__module__
            obj.exception = e.__class__.__name__
            return obj

    mysql_Bin = None

    class MySQLConnection(DBAPI):

        supportTransactions = False
        dbName = 'mysql'
        schemes = [dbName]

        odbc_keywords = ('Server', 'Port', 'UID', 'Password', 'Database')

        def __init__(self, db, user, password='', host='localhost', port=0, **kw):
            drivers = kw.pop('driver', None) or 'mysqldb'
            for driver in drivers.split(','):
                driver = driver.strip()
                if not driver:
                    continue
                try:
                    if driver.lower() in ('mysqldb', 'pymysql'):
                        if driver.lower() == 'pymysql':
                            import pymysql
                            pymysql.install_as_MySQLdb()
                        import MySQLdb
                        if driver.lower() == 'mysqldb':
                            if MySQLdb.version_info[:3] < (1, 2, 2):
                                raise ValueError(
                                    'SQLObject requires MySQLdb 1.2.2 or later')
                        import MySQLdb.constants.CR
                        import MySQLdb.constants.ER
                        self.module = MySQLdb
                        if driver.lower() == 'mysqldb':
                            self.CR_SERVER_GONE_ERROR = \
                                MySQLdb.constants.CR.SERVER_GONE_ERROR
                            self.CR_SERVER_LOST = \
                                MySQLdb.constants.CR.SERVER_LOST
                        else:
                            self.CR_SERVER_GONE_ERROR = \
                                MySQLdb.constants.CR.CR_SERVER_GONE_ERROR
                            self.CR_SERVER_LOST = \
                                MySQLdb.constants.CR.CR_SERVER_LOST
                        self.ER_DUP_ENTRY = MySQLdb.constants.ER.DUP_ENTRY
                    elif driver == 'connector':
                        import mysql.connector
                        self.module = mysql.connector
                        self.CR_SERVER_GONE_ERROR = \
                            mysql.connector.errorcode.CR_SERVER_GONE_ERROR
                        self.CR_SERVER_LOST = \
                            mysql.connector.errorcode.CR_SERVER_LOST
                        self.ER_DUP_ENTRY = mysql.connector.errorcode.ER_DUP_ENTRY
                    elif driver == 'oursql':
                        import oursql
                        self.module = oursql
                        self.CR_SERVER_GONE_ERROR = \
                            oursql.errnos['CR_SERVER_GONE_ERROR']
                        self.CR_SERVER_LOST = oursql.errnos['CR_SERVER_LOST']
                        self.ER_DUP_ENTRY = oursql.errnos['ER_DUP_ENTRY']
                    elif driver == 'mariadb':
                        import mariadb
                        self.module = mariadb
                    elif driver == 'pyodbc':
                        import pyodbc
                        self.module = pyodbc
                    elif driver == 'pypyodbc':
                        import pypyodbc
                        self.module = pypyodbc
                    elif driver == 'odbc':
                        try:
                            import pyodbc
                        except ImportError:
                            import pypyodbc as pyodbc
                        self.module = pyodbc
                    else:
                        raise ValueError(
                            'Unknown MySQL driver "%s", '
                            'expected mysqldb, connector, '
                            'oursql, pymysql, mariadb, '
                            'odbc, pyodbc or pypyodbc' % driver)
                except ImportError:
                    pass
                else:
                    break
            else:
                raise ImportError(
                    'Cannot find a MySQL driver, tried %s' % drivers)
            self.host = host
            self.port = port or 3306
            self.db = db
            self.user = user
            self.password = password
            self.kw = {}
            for key in ("unix_socket", "init_command",
                        "read_default_file", "read_default_group", "conv"):
                if key in kw:
                    self.kw[key] = kw.pop(key)
            for key in ("connect_timeout", "compress", "named_pipe", "use_unicode",
                        "client_flag", "local_infile"):
                if key in kw:
                    self.kw[key] = int(kw.pop(key))
            if driver == 'connector':
                for key in ("ssl_key", "ssl_cert", "ssl_ca", "ssl_capath"):
                    if key in kw:
                        self.kw[key] = kw.pop(key)
            else:
                for key in ("ssl_key", "ssl_cert", "ssl_ca", "ssl_capath"):
                    if key in kw:
                        if "ssl" not in self.kw:
                            self.kw["ssl"] = {}
                        self.kw["ssl"][key[4:]] = kw.pop(key)
            if "charset" in kw:
                self.dbEncoding = self.kw["charset"] = kw.pop("charset")
            else:
                self.dbEncoding = None
            self.driver = driver

            if driver in ('mariadb', 'odbc', 'pyodbc', 'pypyodbc'):
                self.CR_SERVER_GONE_ERROR = 2006
                self.CR_SERVER_LOST = 2013
                self.ER_DUP_ENTRY = '23000'

            if driver in ('odbc', 'pyodbc', 'pypyodbc'):
                self.make_odbc_conn_str(kw.pop('odbcdrv',
                                               'MySQL ODBC 5.3 ANSI Driver'),
                                        db, host, port, user, password
                                        )

            elif driver == 'oursql':
                if "use_unicode" not in self.kw:
                    self.kw["use_unicode"] = not PY2
                # oursql doesn't implement ping(True) yet
                self.kw["autoreconnect"] = True

            elif driver == 'mariadb':
                self.kw.pop("charset", None)

            global mysql_Bin
            if not PY2 and mysql_Bin is None:
                mysql_Bin = self.module.Binary
                self.module.Binary = lambda x: mysql_Bin(x).decode(
                    'ascii', errors='surrogateescape')

            self._server_version = None
            self._can_use_microseconds = None
            self._can_use_json_funcs = None

            DBAPI.__init__(self, **kw)

        @classmethod
        def _connectionFromParams(cls, user, password, host, port, path, args):
            return cls(db=path.strip('/'),
                       user=user or '', password=password or '',
                       host=host or 'localhost', port=port, **args)

        def makeConnection(self):
            dbEncoding = self.dbEncoding
            if dbEncoding:
                if self.driver.lower() in ('mysqldb', 'pymysql'):
                    from MySQLdb.connections import Connection
                    if not hasattr(Connection, 'set_character_set'):
                        # monkeypatch pre MySQLdb 1.2.1
                        def character_set_name(self):
                            return dbEncoding + '_' + dbEncoding
                        Connection.character_set_name = character_set_name
            if self.driver == 'connector':
                self.kw['consume_results'] = True
            try:
                if self.driver in ('odbc', 'pyodbc', 'pypyodbc'):
                    self.debugWriter.write(
                        "ODBC connect string: " + self.odbc_conn_str)
                    conn = self.module.connect(self.odbc_conn_str)
                else:
                    conn = self.module.connect(
                        host=self.host, port=self.port, db=self.db,
                        user=self.user, passwd=self.password, **self.kw)
                    if self.driver == 'mariadb':
                        # Attempt to reconnect.
                        # This setting is persistent due to ``auto_reconnect``.
                        # mariadb doesn't implement ping(True)
                        conn.auto_reconnect = True
                        conn.ping()
                    elif self.driver != 'oursql':
                        # Attempt to reconnect. This setting is persistent.
                        conn.ping(True)
            except self.module.OperationalError as e:
                conninfo = ("; used connection string: "
                            "host=%(host)s, port=%(port)s, "
                            "db=%(db)s, user=%(user)s" % self.__dict__)
                raise dberrors.OperationalError(ErrorMessage(e, conninfo))

            self._setAutoCommit(conn, bool(self.autoCommit))

            if dbEncoding:
                if self.driver in ('odbc', 'pyodbc'):
                    conn.setdecoding(self.module.SQL_CHAR, encoding=dbEncoding)
                    conn.setdecoding(self.module.SQL_WCHAR, encoding=dbEncoding)
                    if PY2:
                        conn.setencoding(str, encoding=dbEncoding)
                        conn.setencoding(unicode, encoding=dbEncoding)  # noqa
                    else:
                        conn.setencoding(encoding=dbEncoding)
                elif hasattr(conn, 'set_character_set'):
                    conn.set_character_set(dbEncoding)
                elif self.driver == 'oursql':
                    conn.charset = dbEncoding
                elif hasattr(conn, 'query'):
                    # works along with monkeypatching code above
                    conn.query("SET NAMES %s" % dbEncoding)

            return conn

        def _setAutoCommit(self, conn, auto):
            if hasattr(conn, 'autocommit'):
                try:
                    conn.autocommit(auto)
                except TypeError:
                    # mysql-connector has autocommit as a property
                    conn.autocommit = auto

        def _force_reconnect(self, conn):
            if self.driver.lower() == 'pymysql':
                conn.ping(True)
                self._setAutoCommit(conn, bool(self.autoCommit))
                if self.dbEncoding:
                    conn.query("SET NAMES %s" % self.dbEncoding)

        def _executeRetry(self, conn, cursor, query):
            if self.debug:
                self.printDebug(conn, query, 'QueryR')
            dbEncoding = self.dbEncoding
            if dbEncoding and not isinstance(query, bytes) and (
                    self.driver in ('mysqldb', 'connector', 'oursql', 'mariadb')):
                query = query.encode(dbEncoding, 'surrogateescape')
            # When a server connection is lost and a query is attempted, most of
            # the time the query will raise a SERVER_LOST exception, then at the
            # second attempt to execute it, the mysql lib will reconnect and
            # succeed. However is a few cases, the first attempt raises the
            # SERVER_GONE exception, the second attempt the SERVER_LOST exception
            # and only the third succeeds. Thus the 3 in the loop count.
            # If it doesn't reconnect even after 3 attempts, while the database is
            # up and running, it is because a 5.0.3 (or newer) server is used
            # which no longer permits autoreconnects by default. In that case a
            # reconnect flag must be set when making the connection to indicate
            # that autoreconnecting is desired. In MySQLdb 1.2.2 or newer this is
            # done by calling ping(True) on the connection.
            # PyMySQL needs explicit reconnect
            # each time we detect connection timeout.
            for count in range(3):
                try:
                    return cursor.execute(query)
                except self.module.OperationalError as e:
                    if e.args[0] in (self.CR_SERVER_GONE_ERROR,
                                     self.CR_SERVER_LOST):
                        if count == 2:
                            raise dberrors.OperationalError(ErrorMessage(e))
                        if self.debug:
                            self.printDebug(conn, str(e), 'ERROR')
                        if self.driver.lower() == 'pymysql':
                            self._force_reconnect(conn)
                    else:
                        raise dberrors.OperationalError(ErrorMessage(e))
                except self.module.IntegrityError as e:
                    msg = ErrorMessage(e)
                    if e.args[0] == self.ER_DUP_ENTRY:
                        raise dberrors.DuplicateEntryError(msg)
                    elif isinstance(e.args[0], str) \
                            and e.args[0].startswith('Duplicate'):
                        raise dberrors.DuplicateEntryError(msg)
                    else:
                        raise dberrors.IntegrityError(msg)
                except self.module.InternalError as e:
                    raise dberrors.InternalError(ErrorMessage(e))
                except self.module.ProgrammingError as e:
                    if e.args[0] is not None:
                        raise dberrors.ProgrammingError(ErrorMessage(e))
                except self.module.DataError as e:
                    raise dberrors.DataError(ErrorMessage(e))
                except self.module.NotSupportedError as e:
                    raise dberrors.NotSupportedError(ErrorMessage(e))
                except self.module.DatabaseError as e:
                    raise dberrors.DatabaseError(ErrorMessage(e))
                except self.module.InterfaceError as e:
                    raise dberrors.InterfaceError(ErrorMessage(e))
                except self.module.Warning as e:
                    raise Warning(ErrorMessage(e))
                except self.module.Error as e:
                    raise dberrors.Error(ErrorMessage(e))

        def _queryInsertID(self, conn, soInstance, id, names, values):
            table = soInstance.sqlmeta.table
            idName = soInstance.sqlmeta.idName
            c = conn.cursor()
            if id is not None:
                names = [idName] + names
                values = [id] + values
            q = self._insertSQL(table, names, values)
            if self.debug:
                self.printDebug(conn, q, 'QueryIns')
            self._executeRetry(conn, c, q)
            if id is None:
                try:
                    id = c.lastrowid
                except AttributeError:
                    try:
                        id = c.insert_id
                    except AttributeError:
                        self._executeRetry(conn, c, "SELECT LAST_INSERT_ID();")
                        id = c.fetchone()[0]
                    else:
                        id = c.insert_id()
            c.close()
            if self.debugOutput:
                self.printDebug(conn, id, 'QueryIns', 'result')
            return id

        @classmethod
        def _queryAddLimitOffset(cls, query, start, end):
            if not start:
                return "%s LIMIT %i" % (query, end)
            if not end:
                return "%s LIMIT %i, -1" % (query, start)
            return "%s LIMIT %i, %i" % (query, start, end - start)

        def createReferenceConstraint(self, soClass, col):
            return col.mysqlCreateReferenceConstraint()

        def createColumn(self, soClass, col):
            return col.mysqlCreateSQL(self)

        def createIndexSQL(self, soClass, index):
            return index.mysqlCreateIndexSQL(soClass)

        def createIDColumn(self, soClass):
            if soClass.sqlmeta.idType == str:
                return '%s TEXT PRIMARY KEY' % soClass.sqlmeta.idName
            return '%s INT PRIMARY KEY AUTO_INCREMENT' % soClass.sqlmeta.idName

        def joinSQLType(self, join):
            return 'INT NOT NULL'

        def tableExists(self, tableName):
            try:
                # Use DESCRIBE instead of SHOW TABLES because SHOW TABLES
                # assumes there is a default database selected
                # which is not always True (for an embedded application, e.g.)
                self.query('DESCRIBE %s' % (tableName))
                return True
            except dberrors.ProgrammingError as e:
                if e.args[0].code in (1146, '42S02'):  # ER_NO_SUCH_TABLE
                    return False
                if self.driver == 'mariadb':
                    return False
                raise

        def addColumn(self, tableName, column):
            self.query('ALTER TABLE %s ADD COLUMN %s' %
                       (tableName,
                        column.mysqlCreateSQL(self)))

        def delColumn(self, sqlmeta, column):
            self.query('ALTER TABLE %s DROP COLUMN %s' % (sqlmeta.table,
                                                          column.dbName))

        def columnsFromSchema(self, tableName, soClass):
            colData = self.queryAll("SHOW COLUMNS FROM %s"
                                    % tableName)
            results = []
            for field, t, nullAllowed, key, default, extra in colData:
                if field == soClass.sqlmeta.idName:
                    continue
                colClass, kw = self.guessClass(t)
                if self.kw.get('use_unicode') and colClass is col.StringCol:
                    colClass = col.UnicodeCol
                    if self.dbEncoding:
                        kw['dbEncoding'] = self.dbEncoding
                kw['name'] = soClass.sqlmeta.style.dbColumnToPythonAttr(field)
                kw['dbName'] = field

                # Since MySQL 5.0, 'NO' is returned in the NULL column
                # (SQLObject expected '')
                kw['notNone'] = (nullAllowed.upper() != 'YES' and True or False)

                if default and t.startswith('int'):
                    kw['default'] = int(default)
                elif default and t.startswith('float'):
                    kw['default'] = float(default)
                elif default == 'CURRENT_TIMESTAMP' and t == 'timestamp':
                    kw['default'] = None
                elif default and colClass is col.BoolCol:
                    kw['default'] = int(default) and True or False
                else:
                    kw['default'] = default
                # @@ skip key...
                # @@ skip extra...
                results.append(colClass(**kw))
            return results

        def guessClass(self, t):
            if t.startswith('int'):
                return col.IntCol, {}
            elif t.startswith('enum'):
                values = []
                for i in t[5:-1].split(','):  # take the enum() off and split
                    values.append(i[1:-1])  # remove the surrounding \'
                return col.EnumCol, {'enumValues': values}
            elif t.startswith('double'):
                return col.FloatCol, {}
            elif t.startswith('varchar'):
                colType = col.StringCol
                if self.kw.get('use_unicode', False):
                    colType = col.UnicodeCol
                if t.endswith('binary'):
                    return colType, {'length': int(t[8:-8]),
                                     'char_binary': True}
                else:
                    return colType, {'length': int(t[8:-1])}
            elif t.startswith('char'):
                if t.endswith('binary'):
                    return col.StringCol, {'length': int(t[5:-8]),
                                           'varchar': False,
                                           'char_binary': True}
                else:
                    return col.StringCol, {'length': int(t[5:-1]),
                                           'varchar': False}
            elif t.startswith('datetime'):
                return col.DateTimeCol, {}
            elif t.startswith('date'):
                return col.DateCol, {}
            elif t.startswith('time'):
                return col.TimeCol, {}
            elif t.startswith('timestamp'):
                return col.TimestampCol, {}
            elif t.startswith('bool'):
                return col.BoolCol, {}
            elif t.startswith('tinyblob'):
                return col.BLOBCol, {"length": 2 ** 8 - 1}
            elif t.startswith('tinytext'):
                return col.StringCol, {"length": 2 ** 8 - 1, "varchar": True}
            elif t.startswith('blob'):
                return col.BLOBCol, {"length": 2 ** 16 - 1}
            elif t.startswith('text'):
                return col.StringCol, {"length": 2 ** 16 - 1, "varchar": True}
            elif t.startswith('mediumblob'):
                return col.BLOBCol, {"length": 2 ** 24 - 1}
            elif t.startswith('mediumtext'):
                return col.StringCol, {"length": 2 ** 24 - 1, "varchar": True}
            elif t.startswith('longblob'):
                return col.BLOBCol, {"length": 2 ** 32}
            elif t.startswith('longtext'):
                return col.StringCol, {"length": 2 ** 32, "varchar": True}
            else:
                return col.Col, {}

        def listTables(self):
            return [v[0] for v in self.queryAll("SHOW TABLES")]

        def listDatabases(self):
            return [v[0] for v in self.queryAll("SHOW DATABASES")]

        def _createOrDropDatabase(self, op="CREATE"):
            self.query('%s DATABASE %s' % (op, self.db))

        def createEmptyDatabase(self):
            self._createOrDropDatabase()

        def dropDatabase(self):
            self._createOrDropDatabase(op="DROP")

        def server_version(self):
            if self._server_version is not None:
                return self._server_version
            try:
                server_version = self.queryOne("SELECT VERSION()")[0]
                server_version = server_version.split('-', 1)
                db_tag = "MySQL"
                if len(server_version) == 2:
                    if "MariaDB" in server_version[1]:
                        db_tag = "MariaDB"
                    server_version = server_version[0]
                server_version = tuple(int(v) for v in server_version.split('.'))
                server_version = (server_version, db_tag)
            except Exception:
                server_version = None  # unknown
            self._server_version = server_version
            return server_version

        def can_use_microseconds(self):
            if self._can_use_microseconds is not None:
                return self._can_use_microseconds
            server_version = self.server_version()
            if server_version is None:
                return None
            server_version, db_tag = server_version
            if db_tag == "MariaDB":
                can_use_microseconds = (server_version >= (5, 3, 0))
            else:  # MySQL
                can_use_microseconds = (server_version >= (5, 6, 4))
            self._can_use_microseconds = can_use_microseconds
            return can_use_microseconds

        def can_use_json_funcs(self):
            if self._can_use_json_funcs is not None:
                return self._can_use_json_funcs
            server_version = self.server_version()
            if server_version is None:
                return None
            server_version, db_tag = server_version
            if db_tag == "MariaDB":
                can_use_json_funcs = (server_version >= (10, 2, 7))
            else:  # MySQL
                can_use_json_funcs = (server_version >= (5, 7, 0))
            self._can_use_json_funcs = can_use_json_funcs
            return can_use_json_funcs