学步园

用python的异常处理和日志可以完整的记录程序发生异常时的出错信息。

这有赖于logging模块的强大和python的错误处理机制。

以下是代码，参考了http://stackoverflow.com/questions/3702675/print-the-full-traceback-in-python-without-halting-the-program

基本范式是：

try:

    do-something-block

except:

    logger.exception("Exception Logged")

def setLogger():
    # 创建一个logger,可以考虑如何将它封装
    logger = logging.getLogger('mylogger')
    logger.setLevel(logging.DEBUG)
    
    # 创建一个handler，用于写入日志文件
    fh = logging.FileHandler(os.path.join(os.getcwd(), 'log.txt'))
    fh.setLevel(logging.DEBUG)
    
    # 再创建一个handler，用于输出到控制台
    ch = logging.StreamHandler()
    ch.setLevel(logging.DEBUG)
    
    # 定义handler的输出格式
    formatter = logging.Formatter('%(asctime)s - %(module)s.%(funcName)s.%(lineno)d - %(levelname)s - %(message)s')
    fh.setFormatter(formatter)
    ch.setFormatter(formatter)
    
    # 给logger添加handler
    logger.addHandler(fh)
    logger.addHandler(ch)
    
    # 记录一条日志
    logger.info('hello world, i\'m log helper in python, may i help you')
    return logger



#对单个表插入一个元组，其定义有
def insertOneData(conn,tableName,listColumn,lData):
    try:
        cursor=conn.cursor()
        sql="insert into "+tableName+"("
        i=0
        length=len(listColumn)
        for column in listColumn:
            if(i!=(length-1)):
                sql=sql+column+","
            else:
                sql=sql+column+") values("
            i=i+1
        for i in range(0,length):
            if(i!=(length-1)):
                sql=sql+"%s,"
            else:
                sql=sql+"%s);"
        logger.info(sql)
        logger.info(lData)
        cursor.execute(sql,lData);
        conn.commit()
    except:
        logger.exception("Exception Logged")

日志的记录形式如下：

2012-04-30 22:29:39,173 - __init__.copyDataWithReplace.135 - ERROR - Exception Logged
Traceback (most recent call last):
  File "C:\Eclipse java EE workspace\ReadExcel\tw_to_microblog\__init__.py", line 133, in copyDataWithReplace
    insertOneData(newConn,newTbl,newColList,lData)
  File "C:\Eclipse java EE workspace\ReadExcel\tw_to_microblog\__init__.py", line 156, in insertOneData
    cursor.execute(sql,lData);
  File "C:\Python27\lib\site-packages\MySQLdb\cursors.py", line 174, in execute
    self.errorhandler(self, exc, value)
  File "C:\Python27\lib\site-packages\MySQLdb\connections.py", line 36, in defaulterrorhandler
    raise errorclass, errorvalue
IntegrityError: (1062, "Duplicate entry '95322' for key 'PRIMARY'")