class OracleCursor:
    """游标类"""

    def __init__(self, cursor, logger, dict_result):
        self.cursor = cursor
        self.logger = logger
        self.dict_result = dict_result

    def _dict_result(self, cursor):
        cols = [d[0].lower() for d in cursor.description]
        def row_factory(*args):
            return dict(zip(cols, args))
        return row_factory

    def execute(self, sql, params=None):
        if params:
            self.cursor.execute(sql, params)
        else:
            self.cursor.execute(sql)

    def query(self, sql, params=None, with_description=False):
        if params:
            self.cursor.execute(sql, params)
        else:
            self.cursor.execute(sql)
        if self.dict_result:
            self.cursor.rowfactory = self._dict_result(self.cursor)
        rows = self.cursor.fetchall()
        if with_description:
            res = rows, self.cursor.description
        else:
            res = rows
        return res


class OracleInstance:
    """实例类"""

    def __init__(self, username, password, host, port, sid,
                 charset='utf8',dict_result=False,logger=None):
        self.username = username
        self.password = password
        self.host = host
        self.port = port
        self.sid = sid
        self.charset = charset
        self.dict_result = dict_result
        if logger is None:
            logger=logging.getLogger(__name__)
        self.logger = logger

    def __enter__(self):
        dsn_tns = cx_Oracle.makedsn(self.host, self.port, self.sid)
        self.con = cx_Oracle.connect(self.username, self.password, dsn_tns)
        self.cursor = self.con.cursor()
        return OracleCursor(self.cursor, self.logger, self.dict_result)

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.cursor.execute("commit")
        self.cursor.close()
        self.con.close()