celery

Posted 2020-12-18 pythonwl

celery的使用

# 1 异步任务框架，执行异步任务，执行延迟任务，执行定时任务
# 2 Celery is a project with minimal funding, so we don’t support Microsoft Windows. Please don’t open any issues related to that platform.

pip install celery

9.1 基本结构

# 只写一个py文件 celery_task
from celery import Celery
broker=‘redis://127.0.0.1:6379/1‘  #broker任务队列
backend=‘redis://127.0.0.1:6379/2‘   # 结构存储，执行完的结果存在这
app=Celery(__name__,broker=broker,backend=backend)

@app.task
def add(x,y):
    print(x,y)
    return x+y

# 启动worker
        # 非windows
celery worker -A celery_task -l info
        # windows：
        # pip3 install eventlet
celery worker -A celery_task -l info -P eventlet
        
# 添加任务
from celery_task import add
add(3,4)  # 直接执行，不会被添加到broker中
ret=add.delay(5,4)  #想broker中添加一个任务

# 查看任务执行结果
	from celery_task import app
    from celery.result import AsyncResult
    id = ‘3e397fd7-e0c1-4c5c-999c-2655a96793bb‘
    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‘)

9.2 包结构

# 新建一个包，celery_task
    -celery_task
        -__init__.py
        -celery.py
        -task1.py
        -task2.py
# celery.py
    from celery import Celery
    broker=‘redis://127.0.0.1:6379/1‘  #broker任务队列
    backend=‘redis://127.0.0.1:6379/2‘# 结构存储，执行完的结果存在这
    app=Celery(__name__,broker=broker,backend=backend,include=[‘celery_task.task1‘,‘celery_task.task2‘])
    
# task.py
    from .celery import app
    @app.task
    def add(x,y):
        print(x,y)
        return x+y
    
# 添加任务（异步任务，延迟任务）
    from celery_task.task1 import add
    from celery_task.task2 import mutile
    #  提交异步
    ret=add.delay(6,7)
    
    # 提交延迟任务
    from datetime import datetime, timedelta
    # 需要utc时间
    eta=datetime.utcnow() + timedelta(seconds=10)
    ret=add.apply_async(args=(240, 50), eta=eta)

9.3 执行定时任务

#1 celery.py
    from celery import Celery
    broker=‘redis://127.0.0.1:6379/1‘  #broker任务队列
    backend=‘redis://127.0.0.1:6379/2‘   # 结构存储，执行完的结果存在这
    app=Celery(__name__,broker=broker,backend=backend,include=[‘celery_task.task1‘,‘celery_task.task2‘])
    # 执行定时任务
    # 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 = {
        ‘add-task‘: {
            ‘task‘: ‘celery_task.task1.add‘,
            # ‘schedule‘: timedelta(seconds=3),
            ‘schedule‘: crontab(hour=8, day_of_week=1),  # 每周一早八点
            ‘args‘: (300, 150),
        }