flask uses scheduled tasks flask_apscheduler (APScheduler)

Flask uses scheduled tasks flask_apscheduler (APScheduler)

2024-07-12

Flask-APScheduler Description:

Flask-APScheduler is a Flask extension that adds support for APScheduler.

APScheduler has three built-in scheduling systems for you to use:

Cron-style scheduling (optional start/end time)
Interval-based execution (run job at even intervals, with optional start/end times)
One-time delayed execution (run a job once at a set date/time)

1. Install the flask_apscheduler library

pip install flask_apscheduler

2. Code in app.py

2.1 Initialize APScheduler


# 创建Flask应用
app = Flask(__name__)
# 初始化APScheduler
scheduler = APScheduler()

2.2 Usage

Describe the use of cron expressions here

Cron expression generator address:https://cron.ciding.cc/

Method 1: Use hard-coded method


# 创建Flask应用
app = Flask(__name__)
# 初始化APScheduler
scheduler = APScheduler()
 
# 方式一硬编码；
# 这些代码也可以放在if __name__ == '__main__':内,与调试运行方式有关，
# 1.flask服务方式运行不会走if __name__ == '__main__':内代码;
# 2.以Python文件(app.py)方式运行会走if __name__ == '__main__':内代码;
scheduler.add_job(func=MyService.my_job, id='my_job', trigger='cron', second='0/5')
scheduler.init_app(app=app)
scheduler.start()

Method 2: Read configuration method

Configuration code


class Config:
    JOBS = [
        {
            'id': 'job1',
            'func': 'app:MyService.my_job',  # 注意这里的格式，app 是 Flask 应用对象的名称(app.py)，: 后面是任务函数名
            'trigger': 'cron',
            # 'day_of_week': '0-6',  # 每天执行
            # 'hour': 18,  # 18 点执行
            # 'inute': 30,  # 30 分执行
            # 'econd': 5  # 0 秒执行
            'second': '0/5'
        }
        # ,
        # {
        #     'id': 'job2',
        #     'func': task2,  # 也可以直接使用函数名
        #     'trigger': 'interval',
        #     'econds': 30  # 每隔 30 秒执行一次
        # }
    ]
    SCHEDULER_API_ENABLED = True


# 创建Flask应用
app = Flask(__name__)
# 初始化APScheduler
scheduler = APScheduler()
 
# 方式一硬编码
# scheduler.add_job(func=MyService.my_job, id='my_job', trigger='cron', second='0/5')
# 方式二读取配置
app.config.from_object(Config())
scheduler.init_app(app=app)
scheduler.start()

3. Code in my_service.py (MyService class)


from datetime import datetime
 
from flask import Flask
 
 
class MyService:
    @classmethod
    def my_job(cls):
        print(f"my_job,当前时间{datetime.now()}")