#conding:utf8

 import pymysql

 import sys

 class TransferMoney(object):

     def __init__(self,conn):

         self.conn=conn

     def check_acct_available(self,acctid):

         cursor = self.conn.cursor()

         try:

             cursor=self.conn.cursor()

             sql="select * from account where acctid=%s"%acctid

             cursor.execute(sql)

             print("check_acct_available:"+sql)

             rs=cursor.fetchall()

             if len(rs)!=1:

                 raise Exception("账号%s不存在："%acctid)

         finally:

             cursor.close()

     def has_enough_money(self,acctid,money):

         cursor = self.conn.cursor()

         try:

             cursor = self.conn.cursor()

             sql = "select * from account where acctid=%s and money>%s" % (acctid,money)

             cursor.execute(sql)

             print("has_enough_money:" + sql)

             rs = cursor.fetchall()

             if len(rs) != 1:

                 raise Exception("账号%s没有足够的钱：" % acctid)

         finally:

             cursor.close()

     def reduce_money(self,acctid,money):

         cursor = self.conn.cursor()

         try:

             cursor = self.conn.cursor()

             sql = "update account set money = money-%s where acctid=%s" % (money,acctid)

             cursor.execute(sql)

             print("reduce_money:" + sql)

             rs = cursor.fetchall()

             if cursor.rowcount!=1:

                 raise Exception("账号%s减款失败：" % acctid)

         finally:

             cursor.close()

     def add_money(self,acctid,money):

         cursor = self.conn.cursor()

         try:

             cursor = self.conn.cursor()

             sql = "update account set money = money+%s where acctid=%s" % (money, acctid)

             cursor.execute(sql)

             print("add_money:" + sql)

             rs = cursor.fetchall()

             if cursor.rowcount != 1:

                 raise Exception("账号%s加款失败：" % acctid)

         finally:

             cursor.close()

     def transfer(self,source_acctid,target_acctid,money):

         '''检查付款人和收款人账号是否存在，检查付款人是否有足够的钱'''

         try:

             self.check_acct_available(source_acctid)

             self.check_acct_available(target_acctid)

             self.has_enough_money(source_acctid,money)

             self.reduce_money(source_acctid,money)

             self.add_money(target_acctid,money)

             self.conn.commit()

         except Exception as e:

              self.conn.rollback()

              raise e

 if __name__=="__main__":

     '''付款人账号id,收款人账号id,转账金额'''

     source_acctid=sys.argv[1]

     target_acctid=sys.argv[2]

     money=sys.argv[3]

     conn=pymysql.connect(

         host='192.168.199.249',

         port=3306,

         user='root',

         passwd='',

         db='imooc',

         charset='utf8'

     )

     tr_money=TransferMoney(conn)

     try:

         tr_money.transfer(source_acctid,target_acctid,money)

     except Exception as e:

         print("出现问题："+str(e))

     finally:

         conn.close()