usos_grades_notify.py

import email.mime.text
import json
import os
import smtplib
import sys
import urllib.parse

import bs4
import requests


URL = "https://logowanie.aps.edu.pl/cas/login?service=https://usosweb.aps.edu.pl/kontroler.php?_action=dla_stud/studia/oceny/index&locale=pl"

USERNAME = os.environ.get("USERNAME")
PASSWORD = os.environ.get("PASSWORD")

DATA_FILE = "data.json"

EMAIL = os.environ.get("EMAIL")


def usage():
    print("""
    Usage:

        %s <cmd>

    Available commands:

        print   download and print grades
        init    download and save grades
        check   download grades, compare with saved, email about changes, save

    """ % sys.argv[0])
    sys.exit(1)


def fetch_grades_page():
    s = requests.Session()

    login_page = bs4.BeautifulSoup(s.get(URL).content, 'html.parser')
    login_form = login_page.form

    form_data = {i["name"]: i["value"] for i in login_form.find_all('input')}
    form_data["username"] = USERNAME
    form_data["password"] = PASSWORD


    grades_response = s.request(
        login_form['method'],
        urllib.parse.urljoin(URL, login_form['action']),
        data=form_data,
    )
    return bs4.BeautifulSoup(grades_response.content, 'html.parser')


def parse_grades(grades_page):
    result = []
    tbodys = grades_page.find_all('tbody')
    for header_tbody, group_tbody in zip(tbodys[::2], tbodys[1::2]):
        group_name = header_tbody.text.split("-")[0].strip()
        for grade_tr in group_tbody.find_all('tr'):
            name = grade_tr.a.text
            grade = " ".join(
                s.text for s in grade_tr.find_all('td')[2].find_all('span')
            )
            result.append((group_name, name, grade))
    return result


def extract_changed(old_grades, grades):
    old_dict = {
        (g[0], g[1]): g[2]
        for g in old_grades
    }
    return list(filter(lambda g: old_dict.get((g[0], g[1])) != g[2], grades))


def notify(changed_grades):
    content = "Changed grades:\n\n" + "\n".join(
        g[1] + ": " + g[2] for g in changed_grades
    )
    print("SENDING NOTIFICATION")
    print(content)

    msg = email.mime.text.MIMEText(content, "plain", "utf-8")
    msg['Subject'] = "Your grades have changed!"
    msg['From'] = "usos_grades_check"
    msg['To'] = EMAIL

    s = smtplib.SMTP('localhost')
    s.send_message(msg)
    s.quit()


def print_():
    grades = parse_grades(fetch_grades_page())
    print(json.dumps(grades, indent=4))


def init():
    grades = parse_grades(fetch_grades_page())
    with open(DATA_FILE, 'w') as f:
        json.dump(grades, f, indent=4)


def check():
    with open(DATA_FILE) as f:
        old_grades = json.load(f)
    grades = parse_grades(fetch_grades_page())
    if not grades:
        print("FAILED TO FETCH GRADES")
        sys.exit(2)
    changed = extract_changed(old_grades, grades)
    if changed:
        notify(changed)
    with open(DATA_FILE, 'w') as f:
        json.dump(grades, f, indent=4)


if __name__ == '__main__':
    if len(sys.argv) < 2:
        usage()
    cmd = sys.argv[1]
    if cmd == "print":
        print_()
    elif cmd == "init":
        init()
    elif cmd == "check":
        check()
    else:
        usage()