1、背景
最近需要做拼音搜索的定时更新功能。因此考虑在拼音搜索的接口里加入定时调度功能，以定时更新拼音搜索的语料库。
但是，采用Flask-APScheduler模块时，在本地测试出现了后台被重复执行了2次的情况。
2、异常项目代码
api_flask.py文件
# api_flask.py
import json
import datetime
from flask_apscheduler import APScheduler
from flask import Flask, request, Response
from api_schedule.calculate import calcu,write
from api_schedule import main
app = Flask(__name__)
num = 0
class Config(object):
JOBS = [
{
'id': '100', # 不重复的标识
'func': 'api_flask:scheduler_job', # 定时执行的 模块：函数
'trigger': 'interval', # 定时执行，其他可选参数data,interval
'seconds': 3
# 'trigger': 'cron', # 定时执行，其他可选参数data,interval
# 'hour': 3, # 每天3：00分执行
# 'minute': 0
}
]
SCHEDULER_API_ENABLED = True
def scheduler_job(): # 一个函数，用来做定时任务的任务。
global num
write()
num += 1
print("后台执行完毕，执行次数num = {}, time = {}".format(num, datetime.datetime.now()))
import importlib
importlib.reload(main)
@app.route('/', methods=['GET', 'POST'])
def api_test():
res = main.main_process()
res_json = json.dumps({'data':res})
print("return res = {}".format(res_json))
return Response(res_json, mimetype='application/json')
def scheduler_init(app):
scheduler = APScheduler()
scheduler.init_app(app)
scheduler.start()
print("scheduler started.")
app.config.from_object(Config)
scheduler_init(app)
if __name__ == '__main__':
app.run(host='0.0.0.0', port=8080, debug=False)
calculate.py文件
#calculate.py
def calcu():
with open('./data.txt', 'r') as f:
res = f.read()
return res
def write():
res = int(calcu())
with open('./data.txt', 'w', encoding='utf-8') as f:
# data.txt里写入一个整数即可。
f.writelines(str(res+1))
if __name__ == '__main__':
print(calcu())
write()
print(calcu())
3、异常日志
D:\Users\Leslie\Anaconda3\python.exe F:/codes/study/api_schedule/api_flask.py
scheduler started.
scheduler started.
* Serving Flask app "api_flask" (lazy loading)
* Environment: production
WARNING: This is a development server. Do not use it in a production deployment.
Use a production WSGI server instead.
* Debug mode: off
* Running on http://0.0.0.0:8080/ (Press CTRL+C to quit)
后台执行完毕，执行次数num = 1, time = 2021-01-05 16:17:02.920408
后台执行完毕，执行次数num = 2, time = 2021-01-05 16:17:02.926411
后台执行完毕，执行次数num = 3, time = 2021-01-05 16:17:05.921030
后台执行完毕，执行次数num = 4, time = 2021-01-05 16:17:05.926030
Process finished with exit code -1
4、解决办法
将定时调度模块的代码放入main函数下，而不是放在上面的主代码块。具体原因还没搞清楚。
即将下面的代码放在 if name == 'main':之后。
注意：app.run(host='0.0.0.0', port=8080, debug=False)中必须设置debug=False，否则会出现另外一种重复执行2次的情况。
def scheduler_init(app):
scheduler = APScheduler()
scheduler.init_app(app)
scheduler.start()
print("scheduler started.")
app.config.from_object(Config)
scheduler_init(app)
调整后的代码：
#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author：Leslie Dang
# File: main.py
# Initial Data : 2020/12/11 16:01
import json
import datetime
from flask_apscheduler import APScheduler
from flask import Flask, request, Response
from api_schedule.calculate import calcu,write
from api_schedule import main
app = Flask(__name__)
num = 0
class Config(object):
JOBS = [
{
'id': '100', # 不重复的标识
'func': 'api_flask:scheduler_job', # 定时执行的 模块：函数
'trigger': 'interval', # 定时执行，其他可选参数data,interval
'seconds': 3
# 'trigger': 'cron', # 定时执行，其他可选参数data,interval
# 'hour': 3, # 每天3：00分执行
# 'minute': 0
}
]
SCHEDULER_API_ENABLED = True
def scheduler_job(): # 一个函数，用来做定时任务的任务。
global num
write()
num += 1
print("后台执行完毕，执行次数num = {}, time = {}".format(num, datetime.datetime.now()))
import importlib
importlib.reload(main)
@app.route('/', methods=['GET', 'POST'])
def api_test():
res = main.main_process()
res_json = json.dumps({'data':res})
print("return res = {}".format(res_json))
return Response(res_json, mimetype='application/json')
if __name__ == '__main__':
def scheduler_init(app):
scheduler = APScheduler()
scheduler.init_app(app)
scheduler.start()
print("scheduler started.")
app.config.from_object(Config)
scheduler_init(app)
app.run(host='0.0.0.0', port=8080, debug=False)
调整后的运行日志
D:\Users\Leslie\Anaconda3\python.exe F:/codes/study/api_schedule/api_flask.py
scheduler started.
* Serving Flask app "api_flask" (lazy loading)
* Environment: production
WARNING: This is a development server. Do not use it in a production deployment.
Use a production WSGI server instead.
* Debug mode: off
* Running on http://0.0.0.0:8080/ (Press CTRL+C to quit)
后台执行完毕，执行次数num = 1, time = 2021-01-05 16:26:29.704507
后台执行完毕，执行次数num = 2, time = 2021-01-05 16:26:32.705826
后台执行完毕，执行次数num = 3, time = 2021-01-05 16:26:35.705605
Process finished with exit code -1