Проверятор состояния посылки, отправленной ShopFans Express. Каждые N минут ходит по указанной ссылке, в случае нового события шлет письмо

main.py

#!/usr/bin/env python3
from datetime import timedelta
import time
import json
import logging
import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

import tornado.ioloop
import requests
from bs4 import BeautifulSoup

log = logging.getLogger(__name__)
logging.basicConfig(format=u'%(asctime)s %(levelname)s %(message)s', level=logging.DEBUG)

TIMEOUT = 60*10  # once in 10 minutes

LOGIN = ''
PASSWORD = ''

FROM_EMAIL = ""
TO_EMAIL = ""
SMTP_SERVER = ''

URL = ''
FILENAME = 'changes.json'


def set_timer(func):
    ioloop = tornado.ioloop.IOLoop.current()
    ioloop.add_timeout(timedelta(seconds=TIMEOUT), func)


class Checker:
    def __init__(self):
        self.changes = {}

    def make_message(self, changes):
        message = []
        for date in sorted(self.changes.keys(), key=lambda x: time.strptime(x, '%Y-%m-%d %H:%M:%S')):
            message.append("<p>{}: {}</p>".format(date, self.changes[date]))
        for new_date, new_event in changes:
            message.append("<p><b>{}</b>: {}</p>".format(new_date, new_event))
        return '\n'.join(message)

    def send_new_changes(self, changes):
        msg = MIMEMultipart('alternative')

        msg['Subject'] = 'New parcel event!'
        msg['From'] = FROM_EMAIL
        msg['To'] = TO_EMAIL

        text = MIMEText(self.make_message(changes), 'html')
        msg.attach(text)

        s = smtplib.SMTP_SSL(SMTP_SERVER)
        s.login(LOGIN, PASSWORD)
        try:
            log.debug('sending new mail to {}'.format(TO_EMAIL))
            s.sendmail(FROM_EMAIL, [TO_EMAIL], msg.as_string())
        finally:
            s.quit()

    def parse_content(self, content):
        parsed = BeautifulSoup(content)
        new_changes = []
        for tr in parsed.table.find_all('tr')[:0:-1]: # newer events are higher
            date, event = [x.text for x in tr.find_all('td')]
            if date not in self.changes:
                new_changes.append((date, event))
                log.info('new event [{}]: {}'.format(date, event))
        if new_changes:
            self.send_new_changes(new_changes)
            self.save_changes(new_changes)
            self.save_changes_to_file()
        else:
            log.info('no new events')

    def check_status(self):
        log.debug('checking parcel status')
        response = requests.get(URL)
        self.parse_content(response.content)
        set_timer(self.check_status)

    def start(self):
        self.load_changes_from_file()
        self.check_status()

    def save_changes(self, changes):
        for date, event in changes:
            self.changes[date] = event

    def save_changes_to_file(self):
        log.debug('saving to file')
        with open(FILENAME, 'w') as f:
            json.dump(self.changes, f)

    def load_changes_from_file(self):
        log.debug('loading changes from file')
        try:
            with open(FILENAME, 'r') as f:
                self.changes = json.load(f)
        except FileNotFoundError:
            log.debug('file not found, so there are no parcel changes yet')
            self.changes = {}


def main():
    checker = Checker()
    checker.start()
    tornado.ioloop.IOLoop.current().start()

if __name__ == '__main__':
    main()

В виде сервиса тут: https://github.com/etataurov/SFX-tracker
работает на http://sfxtracker.herokuapp.com/