Python中APScheduler模块的使用

APScheduler介绍

Advanced Python Scheduler (APScheduler) is a Python library that lets you schedule your Python code to be executed later, either just once or periodically. You can add new jobs or remove old ones on the fly as you please. If you store your jobs in a database,
they will also survive scheduler restarts and maintain their state. When the scheduler is restarted, it will then run all the jobs it should have run while it was offline.

个人翻译：

APScheduler是一个Python库，它能够让你安排你的Python代码延后执行、执行一次或者定期执行。你可以随意添加新的任务或删除旧的任务。如果用数据库存储任务，调度程序重启期间会维护任务的状态。当调度程序重启后，将运行所有本应在掉线时执行的任务。

代码

可以采用两种方式添加任务，调用add_job()方法或使用scheduled_job()装饰器。

调用add_job方法：

import datetime
from apscheduler.schedulers.blocking import BlockingScheduler

scheduler = BlockingScheduler()

def test():
print "now is '%s' " % datetime.datetime.now()

scheduler.add_job(test, "cron", second="*/3")

try:
scheduler.start()
except (KeyboardInterrupt, SystemExit):
scheduler.shutdown()

使用装饰器：

import datetime
from apscheduler.schedulers.blocking import BlockingScheduler

scheduler = BlockingScheduler()

@scheduler.scheduled_job("cron", second="*/3")
def test():
print "now is '%s' " % datetime.datetime.now()

try:
scheduler.start()
except (KeyboardInterrupt, SystemExit):
scheduler.shutdown(

cron表达式说明 

Expression	Field	Description
*	any	Fire on every value
*/a	any	Fire every a values, starting from the minimum
a-b	any	Fire on any value within the a-b range (a must be smaller than b)
a-b/c	any	Fire every c values within the a-b range
xth y	day	Fire on the x -th occurrence of weekday y within the month
last x	day	Fire on the last occurrence of weekday x within the month
last	day	Fire on the last day within the month
x,y,z	any	Fire on any matching expression; can combine any number of any of the above expressions

参考资料

# 官方文档
apschedule_docs = "http://apscheduler.readthedocs.org/en/latest/index.html"

# Python定时任务框架APScheduler 3.0.3 Cron示例
blog1 = "http://www.cnblogs.com/leleroyn/p/4501359.html"