如何在Heroku中运行后台任务? [英] How to run a background task in Heroku?

问题描述

我已经构建了一个python应用程序，并使用 Flask 和 Python 进行了部署.这是我的代码的斯凯尔顿.

I have already build a a python app and deployed it using Flask and Python. Here is my Skelton of my code.

#app.py
@app.route('/', methods=['GET'])
def login():
    '''login process'''

@app.route('/reset-password', methods=['GET'])
def reset_password():
    '''reset password process'''

@app.route('/add-psa', methods=['GET'])
def add_user():
    '''add user process'''

if __name__ == '__main__':
    app.debug = True
    app.run(use_reloader=False, threaded=True)

已部署的应用程序在Heroku中工作正常.但是根据Heroku 此教程来运行后台作业.这是我到目前为止所做的

Deployed app work fine in the Heroku. But sometime it takes more than 30 seconds to response which means H12 error according to Heroku doc. So I followed this tutorial to run background job. Here is what I've done so far

#worker.py
import os

import redis
from rq import Worker, Queue, Connection

listen = ['high', 'default', 'low']

redis_url = os.getenv('REDISTOGO_URL', 'redis://localhost:6379')

conn = redis.from_url(redis_url)

if __name__ == '__main__':
    with Connection(conn):
        worker = Worker(map(Queue, listen))
        worker.work()

下一步...

#utils.py
import requests

def count_words_at_url(url):
    resp = requests.get(url)
    return len(resp.text.split())

我还更改了 Procfile 和 requirements.txt

我想在后台运行我的 reset_password()，因为它花费的时间超过 30秒.有人可以帮助我吗?

I want to run my reset_password() in background since its taking more than 30seconds. Any one who can help me on this?

推荐答案

一种解决方案是从Web请求中生成线程:在这种情况下，可以在后台线程启动并执行必要的操作时立即(几乎)返回响应.任务(不受HTTP超时限制)

A solution is to spawn a thread from the web request: in this case the response can be returned (almost) immediately while a background thread starts and performs the necessary task (without the constraint of the HTTP timeout)

# my background thread
class MyWorker():

  def __init__(self, message):
    self.message = message

    thread = threading.Thread(target=self.run, args=())
    thread.daemon = True
    thread.start()

  def run(self):
    logging.info(f'run MyWorker with parameter {self.message}')

    # do something

Web请求创建线程的实例，并可以通知调用方正在进行的操作(或应用其他工作流/消息)

The web request creates an instance of the thread and could inform the caller something is in progress (or apply a different workflow/message)

#app.py
@app.route('/reset-password', methods=['GET'])
def reset_password():
'''reset password process'''
   MyWorker('param_value')
   return "In progress... You will receive an email"

这篇关于如何在Heroku中运行后台任务?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！