Celery
简介
Celery是由Python开发的一个简单、灵活、可靠的处理大量任务的分发系统，它不仅支持实时处理也支持任务调度。
- user：用户程序，用于告知celery去执行一个任务。
- broker: 存放任务（依赖RabbitMQ或Redis，进行存储）
- worker：执行任务
celery需要rabbitMQ、Redis、Amazon SQS、Zookeeper（测试中） 充当broker来进行消息的接收，并且也支持多个broker和worker来实现高可用和分布式。http://docs.celeryproject.org/en/latest/getting-started/brokers/index.html
版本和要求：
Celery version 4.0 runs on Python ❨2.7, 3.4, 3.5❩ PyPy ❨5.4, 5.5❩ This is the last version to support Python 2.7, and from the next version (Celery 5.x) Python 3.5 or newer is required. If you’re running an older version of Python, you need to be running an older version of Celery: Python 2.6: Celery series 3.1 or earlier. Python 2.5: Celery series 3.0 or earlier. Python 2.4 was Celery series 2.2 or earlier. Celery is a project with minimal funding, so we don’t support Microsoft Windows. Please don’t open any issues related to that platform.
环境准备：
- 安装rabbitMQ或Redis
- 安装celery
pip3 install celery
快速上手
s1.py
import time from celery import Celery app = Celery('tasks', broker='redis://192.168.10.48:6379', backend='redis://192.168.10.48:6379') @app.task def xxxxxx(x, y): time.sleep(10) return x + y
s2.py
# -*- coding:utf-8 -*- from s1 import xxxxxx # 立即告知celery去执行xxxxxx任务，并传入两个参数 result = xxxxxx.delay(4, 4) print(result.id)
s3.py
from celery.result import AsyncResult from s1 import app async = AsyncResult(id="f0b41e83-99cf-469f-9eff-74c8dd600002", app=app) if async.successful(): result = async.get() print(result) # result.forget() # 将结果删除 elif async.failed(): print('执行失败') elif async.status == 'PENDING': print('任务等待中被执行') elif async.status == 'RETRY': print('任务异常后正在重试') elif async.status == 'STARTED': print('任务已经开始被执行')
执行 s1.py 创建worker（终端执行命令）：
celery worker -A s1 -l info
执行 s2.py ，创建一个任务并获取任务ID：
python3 s2.py
执行 s3.py ,检查任务状态并获取结果：
python3 s3.py
多任务结构
pro_cel ├── celery_tasks# celery相关文件夹 │ ├── celery.py # celery连接和配置相关文件 │ └── tasks.py # 所有任务函数 ├── check_result.py # 检查结果 └── send_task.py # 触发任务
pro_cel/celery_tasks/celery
# -*- coding:utf-8 -*- from celery import Celery celery = Celery('xxxxxx', broker='redis://192.168.0.111:6379', backend='redis://192.168.0.111:6379', include=['celery_tasks.tasks']) # 时区 celery.conf.timezone = 'Asia/Shanghai' # 是否使用UTC celery.conf.enable_utc = False pro_cel/celery_tasks/celery
pro_cel/celery_tasks/tasks.py
# -*- coding:utf-8 -*- import time from .celery import celery @celery.task def xxxxx(*args, **kwargs): time.sleep(5) return "任务结果" @celery.task def hhhhhh(*args, **kwargs): time.sleep(5) return "任务结果" pro_cel/celery_tasks/tasks.py
pro_cel/check_result.py
# -*- coding:utf-8 -*- from celery.result import AsyncResult from celery_tasks.celery import celery async = AsyncResult(id="ed88fa52-11ea-4873-b883-b6e0f00f3ef3", app=celery) if async.successful(): result = async.get() print(result) # result.forget() # 将结果删除 elif async.failed(): print('执行失败') elif async.status == 'PENDING': print('任务等待中被执行') elif async.status == 'RETRY': print('任务异常后正在重试') elif async.status == 'STARTED': print('任务已经开始被执行') pro_cel/check_result.py
pro_cel/send_task.py
# -*- coding:utf-8 -*- import celery_tasks.tasks # 立即告知celery去执行xxxxxx任务，并传入两个参数 result = celery_tasks.tasks.xxxxx.delay(4, 4) print(result.id) pro_cel/send_task.py
更多配置：http://docs.celeryproject.org/en/latest/userguide/configuration.html
定时任务
1. 设定时间让celery执行一个任务
import datetime from celery_tasks.tasks import xxxxx """ from datetime import datetime v1 = datetime(2017, 4, 11, 3, 0, 0) print(v1) v2 = datetime.utcfromtimestamp(v1.timestamp()) print(v2) """ ctime = datetime.datetime.now() utc_ctime = datetime.datetime.utcfromtimestamp(ctime.timestamp()) s10 = datetime.timedelta(seconds=10) ctime_x = utc_ctime + s10 # 使用apply_async并设定时间 result = xxxxx.apply_async(args=[1, 3], eta=ctime_x) print(result.id)
2. 类似于contab的定时任务
""" celery beat -A proj celery worker -A proj -l info """ from celery import Celery from celery.schedules import crontab app = Celery('tasks', broker='amqp://47.98.134.86:5672', backend='amqp://47.98.134.86:5672', include=['proj.s1', ]) app.conf.timezone = 'Asia/Shanghai' app.conf.enable_utc = False app.conf.beat_schedule = { # 'add-every-10-seconds': { # 'task': 'proj.s1.add1', # 'schedule': 10.0, # 'args': (16, 16) # }, 'add-every-12-seconds': { 'task': 'proj.s1.add1', 'schedule': crontab(minute=42, hour=8, day_of_month=11, month_of_year=4), 'args': (16, 16) }, }
注：如果想要定时执行类似于crontab的任务，需要定制 Scheduler来完成。
Flask中应用Celery
pro_flask_celery/
├── app.py
├── celery_tasks
├── celery.py
└── tasks.py
app.py
# -*- coding:utf-8 -*- from flask import Flask from celery.result import AsyncResult from celery_tasks import tasks from celery_tasks.celery import celery app = Flask(__name__) TASK_ID = None @app.route('/') def index(): global TASK_ID result = tasks.xxxxx.delay() # result = tasks.task.apply_async(args=[1, 3], eta=datetime(2018, 5, 19, 1, 24, 0)) TASK_ID = result.id return "任务已经提交" @app.route('/result') def result(): global TASK_ID result = AsyncResult(id=TASK_ID, app=celery) if result.ready(): return result.get() return "xxxx" if __name__ == '__main__': app.run()
celery_tasks/celery.py
# -*- coding:utf-8 -*- from celery import Celery from celery.schedules import crontab celery = Celery('xxxxxx', broker='redis://192.168.10.48:6379', backend='redis://192.168.10.48:6379', include=['celery_tasks.tasks']) # 时区 celery.conf.timezone = 'Asia/Shanghai' # 是否使用UTC celery.conf.enable_utc = False
celery_task/tasks.py
# -*- coding:utf-8 -*- import time from .celery import celery @celery.task def hello(*args, **kwargs): print('执行hello') return "hello" @celery.task def xxxxx(*args, **kwargs): print('执行xxxxx') return "xxxxx" @celery.task def hhhhhh(*args, **kwargs): time.sleep(5) return "任务结果"
Django中应用Celery
一、基本使用
django_celery_demo ├── app01 │ ├── __init__.py │ ├── admin.py │ ├── apps.py │ ├── migrations │ ├── models.py │ ├── tasks.py │ ├── tests.py │ └── views.py ├── db.sqlite3 ├── django_celery_demo │ ├── __init__.py │ ├── celery.py │ ├── settings.py │ ├── urls.py │ └── wsgi.py ├── manage.py ├── red.py └── templates
django_celery_demo/celery.py
# -*- coding:utf-8 -*- import os from celery import Celery # set the default Django settings module for the 'celery' program. os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'django_celery_demo.settings') app = Celery('django_celery_demo') # Using a string here means the worker doesn't have to serialize # the configuration object to child processes. # - namespace='CELERY' means all celery-related configuration keys # should have a `CELERY_` prefix. app.config_from_object('django.conf:settings', namespace='CELERY') # Load task modules from all registered Django app configs. app.autodiscover_tasks()
django_celery_demo/__init__.py
from .celery import app as celery_app __all__ = ('celery_app',)
app01/tasks.py
from celery import shared_task @shared_task def add(x, y): return x + y @shared_task def mul(x, y): return x * y @shared_task def xsum(numbers): return sum(numbers)
django_celery_demo/settings.py
... .... ..... # ######################## Celery配置 ######################## CELERY_BROKER_URL = 'redis://10.211.55.20:6379' CELERY_ACCEPT_CONTENT = ['json'] CELERY_RESULT_BACKEND = 'redis://10.211.55.20:6379' CELERY_TASK_SERIALIZER = 'json'
app01/views.py
from django.shortcuts import render, HttpResponse from app01 import tasks from django_celery_demo import celery_app from celery.result import AsyncResult def index(request): result = tasks.add.delay(1, 8) print(result) return HttpResponse('...') def check(request): task_id = request.GET.get('task') async = AsyncResult(id=task_id, app=celery_app) if async.successful(): data = async.get() print('成功', data) else: print('任务等待中被执行') return HttpResponse('...')
django_celery_demo/urls.py
"""django_celery_demo URL Configuration The `urlpatterns` list routes URLs to views. For more information please see: https://docs.djangoproject.com/en/1.11/topics/http/urls/ Examples: Function views 1. Add an import: from my_app import views 2. Add a URL to urlpatterns: url(r'^$', views.home, name='home') Class-based views 1. Add an import: from other_app.views import Home 2. Add a URL to urlpatterns: url(r'^$', Home.as_view(), name='home') Including another URLconf 1. Import the include() function: from django.conf.urls import url, include 2. Add a URL to urlpatterns: url(r'^blog/', include('blog.urls')) """ from django.conf.urls import url from django.contrib import admin from app01 import views urlpatterns = [ url(r'^admin/', admin.site.urls), url(r'^index/', views.index), url(r'^check/', views.check), ]
二、定时任务
1. 安装
install django-celery-beat
2. 注册app
INSTALLED_APPS = ( ..., 'django_celery_beat', )
3. 数据库去迁移生成定时任务相关表
python manage.py migrate
4. 设置定时任务
方式一：代码中配置
django_celery_demo/celery.py
# -*- coding:utf-8 -*- import os from celery import Celery # set the default Django settings module for the 'celery' program. os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'django_celery_demo.settings') app = Celery('django_celery_demo') # Using a string here means the worker doesn't have to serialize # the configuration object to child processes. # - namespace='CELERY' means all celery-related configuration keys # should have a `CELERY_` prefix. app.config_from_object('django.conf:settings', namespace='CELERY') app.conf.beat_schedule = { 'add-every-5-seconds': { 'task': 'app01.tasks.add', 'schedule': 5.0, 'args': (16, 16) }, } # Load task modules from all registered Django app configs. app.autodiscover_tasks()
方式二：数据表录入
5. 后台进程创建任务
celery -A django_celery_demo beat -l info --scheduler django_celery_beat.schedulers:DatabaseScheduler
6. 启动worker执行任务
celery -A django_celery_demo worker -l INFO
官方参考：http://docs.celeryproject.org/en/latest/django/first-steps-with-django.html#using-celery-with-django
