相关课程：http://www.imooc.com/video/9219/0
# coding:utf8
import sys
# Python3 采用pymysql 连接MySQL
import pymysql
class TransferMoney(object):
def __init__(self,conn):
self.conn=conn
def check_acct_available(self,acctid):
cursor = self.conn.cursor()
try:
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:
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余额不足"% acctid)
finally:
cursor.close()
def reduce_money(self,acctid,money):
cursor = self.conn.cursor()
try:
sql="update account set money=money-%s where acctid=%s" % (money,acctid)
cursor.execute(sql)
print ("reduce_money:"+sql)
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:
sql="update account set money=money+%s where acctid=%s" % (money,acctid)
cursor.execute(sql)
print ("add_money:"+sql)
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):
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__":
source_acctid=sys.argv[1]
target_acctid=sys.argv[2]
money=sys.argv[3]
conn = pymysql.Connect(
host='localhost',
unix_socket="/Applications/MAMP/tmp/mysql/mysql.sock",
port=3306,
user='root',
passwd='123456',
db='python_db',
)
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()
