python-定时任务-apschelduer

1. apscheduler

1.1. install

pip install apscheduler

1.2. basic concepts

APScheduler has four kinds of components:

  • triggers
  • job stores
  • executors
  • schedulers

Your choice of scheduler depends mostly on your programming environment and what you’ll be using APScheduler for. Here’s a quick guide for choosing a scheduler:

  • BlockingScheduler: use when the scheduler is the only thing running in your process
  • BackgroundScheduler: use when you’re not using any of the frameworks below, and want the scheduler to run in the background inside your application
  • AsyncIOScheduler: use if your application uses the asyncio module
  • GeventScheduler: use if your application uses gevent
  • TornadoScheduler: use if you’re building a Tornado application
  • TwistedScheduler: use if you’re building a Twisted application
  • QtScheduler: use if you’re building a Qt application

需要注意的是前两种方式,一为阻塞型,一为非阻塞型。具体差别见后文。

job stores主要影响作业持久化,一般情况下使用默认方式default (MemoryJobStore)足够了,如果需要持久化,可能就得需要数据库支持了,例如SQLAlchemyJobStore。

exeutors主要有ThreadPoolExecutorProcessPoolExecutor,默认是前者,一般够用,除非是cpu密集型作业。

APScheduler comes with three built-in trigger types:

  • date: use when you want to run the job just once at a certain point of time
  • interval: use when you want to run the job at fixed intervals of time
  • cron: use when you want to run the job periodically at certain time(s) of day

1.2.1. 示例

schedule.add_job(func=job1,trigger='interval', seconds=1)

schedule.add_job(func=job2, args=('lierl',), trigger='date', next_run_time=datetime.datetime.now()+datetime.timedelta(seconds=5))

schedule.add_job(func=job1, trigger='cron', month='1,3,5,7-9', day='*', hour='14', minute='*')

1.3. scheduler manage

scheduler.start()

scheduler.shutdown()

scheduler.pause()

This will cause the scheduler to not wake up until processing is resumed:

scheduler.resume()

It is also possible to start the scheduler in paused state, that is, without the first wakeup call:

scheduler.start(paused=True)

1.4. job administer add /remove/pause/resume/list/modify

There are two ways to add jobs to a scheduler:

  1. by calling add_job()
  2. by decorating a function with scheduled_job()

When you remove a job from the scheduler, it is removed from its associated job store and will not be executed anymore. There are two ways to make this happen:

  1. by calling remove_job() with the job’s ID and job store alias
  2. by calling remove() on the Job instance you got from add_job()

You can easily pause and resume jobs through either the Job instance or the scheduler itself. When a job is paused, its next run time is cleared and no further run times will be calculated for it until the job is resumed. To pause a job, use either method:

To resume:

获取当前任务列表

  1. get_jobs():It will return a list of Job instances. If you’re only interested in the jobs contained in a particular job store, then give a job store alias as the second argument.
  2. print_jobs():will print out a formatted list of jobs, their triggers and next run times.

2. 基本使用

2.1. 阻塞/非阻塞

下面是一个非阻塞型的定时任务调度。

#sys

import threading

import apscheduler

import time, datetime

from apscheduler.schedulers.blocking import BlockingScheduler

from apscheduler.schedulers.background import BackgroundScheduler

para = [1,2,3,4]

continue_run = True

def job1():

print('job1')

print(threading.current_thread())

print(time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

def job2(*args):

global para

print('job2', para)

print(threading.current_thread())

print(time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

def stop_runing():

global continue_run

continue_run = False

#sch = BlockingScheduler()

sch = BackgroundScheduler()

sch.add_job(job1, 'interval', seconds=5)

sch.add_job(job2, 'interval', seconds=8)

sch.add_job(stop_runing, 'date', run_date='2019-6-16 12:25:00',)

jl = sch.get_jobs() #[<Job (id=66307271d51f451491fd7bf8e8ebfc47 name=job1)>, <Job (id=af6ddd2c0ed94df58d889637cb7b816d name=job2)>]

sch.print_jobs()

print('main thread:', threading.current_thread())

print('before scheduler:', time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

sch.start()

while continue_run:

print('main')

time.sleep(10)

print('program ending.')

2.2. 执行时间问题

import threading

import apscheduler

import time, datetime

from apscheduler.schedulers.blocking import BlockingScheduler

from apscheduler.schedulers.background import BackgroundScheduler

continue_run = True

def aps_schduler():

para = [1,2,3,4]

def job1():

print('job1')

print(threading.current_thread())

print(time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

def job2(*args, ):

print('job2', args)

print(threading.current_thread())

print(time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

def stop_runing():

global continue_run

continue_run = False

#sch = BlockingScheduler()

sch = BackgroundScheduler()

#添加定时任务

sch.add_job(job1, 'interval', seconds=5)

sch.add_job(job2, 'interval', seconds=8, args=['text'])

# 1分钟后执行stop_running

sch.add_job(stop_runing, 'date', run_date=time.strftime( '%Y-%m-%d %H:%M:%S', time.localtime(time.time()+60)))

jl = sch.get_jobs() #[<Job (id=66307271d51f451491fd7bf8e8ebfc47 name=job1)>, <Job (id=af6ddd2c0ed94df58d889637cb7b816d name=job2)>]

sch.print_jobs()

print('main thread:', threading.current_thread())

print('before scheduler:', time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

sch.start()

while continue_run:

print('main')

time.sleep(10)

print('program ending.')

aps_schduler()

2.3. 超时问题

如果使用非阻塞模式,不存在超时问题,每次都会启一个新线程,直到达到max_instances给出的限制。

这里把实例限制设为1:

Execution of job "aps_schduler.<locals>.job1 (trigger: interval[0:00:03], next run at: 2019-06-16 16:19:35 CST)" skipped: maximum number of running instances reached (1)

每次调度启动任务时冲突,会抛出一个异常信息,但不会终止执行;否则正常进行。

示例代码:

import threading

import apscheduler

import time, datetime

from apscheduler.schedulers.blocking import BlockingScheduler

from apscheduler.schedulers.background import BackgroundScheduler

continue_run = True

def aps_schduler():

para = [1,2,3,4]

count_x = 1

def job1():

nonlocal count_x

count_x +=1

print('job1')

print(threading.current_thread())

print(time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

time.sleep(15)

print(count_x)

def stop_runing():

global continue_run

continue_run = False

sch = BackgroundScheduler()

#添加定时任务

sch.add_job(job1, 'interval', seconds=3, max_instances=1)

# 1分钟后执行stop_running

sch.add_job(stop_runing, 'date', run_date=time.strftime( '%Y-%m-%d %H:%M:%S', time.localtime(time.time()+60)))

print('main thread:', threading.current_thread())

print('before scheduler:', time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

sch.start()

while continue_run:

print('main')

time.sleep(5)

print('program ending.')

aps_schduler()

2.4. 首次执行时间问题

与twisted的定时任务类似,它也不会在一开始就执行;

除非指定:

sch.add_job(job1, 'interval', seconds=5, max_instances=1, next_run_time=datetime.datetime.now())

当然,在开始定时任务前手动执行一次也是可行的。

2.5. 其它设置

任务多实例

add_job有max_instances参数可以控制多任务实例

3. api

3.1. date apscheduler.triggers.date

fromdatetimeimport date

fromapscheduler.schedulers.blockingimport BlockingScheduler

sched = BlockingScheduler()

def my_job(text):

print(text)

# The job will be executed on November 6th, 2009

sched.add_job(my_job, 'date', run_date=date(2009, 11, 6), args=['text'])

sched.start()

You can specify the exact time when the job should be run:

# The job will be executed on November 6th, 2009 at 16:30:05

sched.add_job(my_job, 'date', run_date=datetime(2009, 11, 6, 16, 30, 5), args=['text'])

The run date can be given as text too:

sched.add_job(my_job, 'date', run_date='2009-11-06 16:30:05', args=['text'])

To add a job to be run immediately:

# The 'date' trigger and datetime.now() as run_date are implicit

sched.add_job(my_job, args=['text'])

4. 参考文档

参考文档:

https://apscheduler.readthedocs.io/en/latest/userguide.html#starting-the-scheduler

5. testing code

5.1. example1

import threading

import apscheduler

import time, datetime

from apscheduler.schedulers.blocking import BlockingScheduler

from apscheduler.schedulers.background import BackgroundScheduler

continue_run = True

def aps_schduler():

para = [1,2,3,4]

count_x = 1

def job1():

nonlocal count_x

count_x +=1

print('job1')

print(threading.current_thread())

print(time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

#time.sleep(15)

print(count_x)

def stop_runing():

global continue_run

continue_run = False

sch = BackgroundScheduler()

#添加定时任务

sch.add_job(job1, 'interval', seconds=5, max_instances=1, next_run_time=datetime.datetime.now())

# 1分钟后执行stop_running

sch.add_job(stop_runing, 'date', run_date=time.strftime( '%Y-%m-%d %H:%M:%S', time.localtime(time.time()+60)))

print('main thread:', threading.current_thread())

print('before scheduler:', time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()))

sch.start()

while continue_run:

#print('main')

time.sleep(5)

print('program ending.')

aps_schduler()