celery框架

Celery

官方

Celery 官网:http://www.celeryproject.org/

Celery 官方文档英文版:http://docs.celeryproject.org/en/latest/index.html

Celery 官方文档中文版:http://docs.jinkan.org/docs/celery/

Celery架构 

Celery的架构由三部分组成,消息中间件(message broker)、任务执行单元(worker)和 任务执行结果存储(backend - task result store)组成。

消息中间件

Celery本身不提供消息服务,但是可以方便的和第三方提供的消息中间件集成。包括,RabbitMQ, Redis等等

任务执行单元

Worker是Celery提供的任务执行的单元,worker并发的运行在分布式的系统节点中。

任务结果存储

Task result store用来存储Worker执行的任务的结果,Celery支持以不同方式存储任务的结果,包括AMQP, redis等

使用场景

异步任务:将耗时操作任务提交给Celery去异步执行,比如发送短信/邮件、消息推送、音视频处理等等

定时任务:定时执行某件事情,比如每天数据统计

Celery的安装配置

pip install celery

 

消息中间件 RabbitMQ/Redis

app=celery.Celery('任务名', broker='xxx', backend='xxx', include=['xxx', 'xxx'])

Celery执行异步任务

  包架构封装

project
    ├── celery_task      # celery包
    │   ├── __init__.py # 包文件
    │   ├── celery.py   # celery连接和配置相关文件,且名字必须交celery.py
    │   └── tasks.py    # 所有任务函数
    ├── add_task.py      # 添加任务
    └── get_result.py   # 获取结果

 

 

 

基本使用方法

# 1)创建app + 任务

# 2)启动celery(app)服务:
# 非windows
# 命令:celery worker -A celery_task -l info
# windows:
# pip3 install eventlet
# celery worker -A celery_task -l info -P eventlet

# 3)添加任务:手动添加,要自定义添加任务的脚本,右键执行脚本

# 4)获取结果:手动获取,要自定义获取任务的脚本,右键执行脚本


from celery import Celery

broker = 'redis://127.0.0.1:6379/1'
backend = 'redis://127.0.0.1:6379/2'
app = Celery(broker=broker, backend=backend, include=['celery_task.tasks'])

 

tasks.py

from .celery import app
import time
@app.task
def add(n, m):
    print(n)
    print(m)
    time.sleep(10)
    print('n+m的结果:%s' % (n + m))
    return n + m

@app.task
def low(n, m):
    print(n)
    print(m)
    print('n-m的结果:%s' % (n - m))
    return n - m

 

add_task.py

from celery_task import tasks

# 添加立即执行任务
t1 = tasks.add.delay(10, 20)
t2 = tasks.low.delay(100, 50)
print(t1.id)


# 添加延迟任务
from datetime import datetime, timedelta
def eta_second(second):
    ctime = datetime.now()
    utc_ctime = datetime.utcfromtimestamp(ctime.timestamp())
    time_delay = timedelta(seconds=second)
    return utc_ctime + time_delay

tasks.low.apply_async(args=(200, 50), eta=eta_second(10))

get_result.py

from celery_task.celery import app

from celery.result import AsyncResult

id = '21325a40-9d32-44b5-a701-9a31cc3c74b5'
if __name__ == '__main__':
    async = AsyncResult(id=id, app=app)
    if async.successful():
        result = async.get()
        print(result)
    elif async.failed():
        print('任务失败')
    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')

高级使用

celery.py

# 1)创建app + 任务

# 2)启动celery(app)服务:
# 非windows
# 命令:celery worker -A celery_task -l info
# windows:
# pip3 install eventlet
# celery worker -A celery_task -l info -P eventlet

# 3)添加任务:自动添加任务,所以要启动一个添加任务的服务
# 命令:celery beat -A celery_task -l info

# 4)获取结果


from celery import Celery

broker = 'redis://127.0.0.1:6379/1'
backend = 'redis://127.0.0.1:6379/2'
app = Celery(broker=broker, backend=backend, include=['celery_task.tasks'])


# 时区
app.conf.timezone = 'Asia/Shanghai'
# 是否使用UTC
app.conf.enable_utc = False

# 任务的定时配置
from datetime import timedelta
from celery.schedules import crontab
app.conf.beat_schedule = {
    'low-task': {
        'task': 'celery_task.tasks.low',
        'schedule': timedelta(seconds=3),
        # 'schedule': crontab(hour=8, day_of_week=1),  # 每周一早八点
        'args': (300, 150),
    }
}

 

tasks.py

from .celery import app

import time
@app.task
def add(n, m):
    print(n)
    print(m)
    time.sleep(10)
    print('n+m的结果:%s' % (n + m))
    return n + m


@app.task
def low(n, m):
    print(n)
    print(m)
    print('n-m的结果:%s' % (n - m))
    return n - m

 

get_result.py

from celery_task.celery import app

from celery.result import AsyncResult

id = '21325a40-9d32-44b5-a701-9a31cc3c74b5'
if __name__ == '__main__':
    async = AsyncResult(id=id, app=app)
    if async.successful():
        result = async.get()
        print(result)
    elif async.failed():
        print('任务失败')
    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')

django中使用

celery.py

# 重点:要将 项目名.settings 所占的文件夹添加到环境变量
# import sys
# sys.path.append(r'项目绝对路径')

# 开启django支持
import os
os.environ.setdefault('DJANGO_SETTINGS_MODULE', '项目名.settings')
import django
django.setup()



# 1)创建app + 任务

# 2)启动celery(app)服务:
# 非windows
# 命令:celery worker -A celery_task -l info
# windows:
# pip3 install eventlet
# celery worker -A celery_task -l info -P eventlet

# 3)添加任务:自动添加任务,所以要启动一个添加任务的服务
# 命令:celery beat -A celery_task -l info

# 4)获取结果


from celery import Celery

broker = 'redis://127.0.0.1:6379/1'
backend = 'redis://127.0.0.1:6379/2'
app = Celery(broker=broker, backend=backend, include=['celery_task.tasks'])


# 时区
app.conf.timezone = 'Asia/Shanghai'
# 是否使用UTC
app.conf.enable_utc = False

# 任务的定时配置
from datetime import timedelta
from celery.schedules import crontab
app.conf.beat_schedule = {
    'django-task': {
        'task': 'celery_task.tasks.test_django_celery',
        'schedule': timedelta(seconds=3),
        'args': (),
    }
}

tasks.py

from .celery import app

from home.models import Banner
from settings.const import BANNER_COUNT  # 轮播图最大显示条数
from home.serializers import BannerModelSerializer
from django.core.cache import cache
@app.task
def update_banner_list():
    # 获取最新内容
    banner_query = Banner.objects.filter(is_delete=False, is_show=True).order_by('-orders')[:BANNER_COUNT]
    # 序列化
    banner_data = BannerModelSerializer(banner_query, many=True).data
    for banner in banner_data:
        banner['image'] = 'http://127.0.0.1:8000' + banner['image']
    # 更新缓存
    cache.set('banner_list', banner_data)
    return True
posted @ 2019-11-01 00:32  LD_Dragon  阅读(215)  评论(0编辑  收藏  举报