1import asyncio
 2from datetime import datetime, timedelta
 3
 4from app.config import NOTIFY_DAYS_LEFT
 5from app.db import GetDB
 6from app.db.models import User
 7from app.models.notification import UserNotification
 8from app.models.user import UserResponse
 9from app.notification.notifiers import notify
10
11
12async def expire_days_reached():
13    """
14    Identifies users whose expiration days have reached a predefined notification period and sends notifications.
15
16    This function checks each active user with an expiration date set and determines if they are within a
17    specific notification window (`NOTIFY_DAYS_LEFT` days before expiration). If the condition is met,
18    it sends a notification.
19
20    How it works:
21    - The current UTC time is obtained.
22    - For each user in the database who is activated and currently active, check if their expiration date is set.
23    - If the user's expiration date is within the `NOTIFY_DAYS_LEFT` threshold (plus a 30-second margin),
24      log the event and trigger a notification.
25    """
26
27    now = datetime.utcnow()
28    cleft = timedelta(days=NOTIFY_DAYS_LEFT) + now
29    cright = timedelta(days=NOTIFY_DAYS_LEFT, seconds=30) + now
30    with GetDB() as db:
31        users = db.query(User).filter(
32            User.is_active == True,
33            User.activated == True,
34            User.expire_date.isnot(None),
35            User.expire_date.between(cleft, cright),
36        )
37        for user in users:
38            asyncio.ensure_future(
39                notify(
40                    action=UserNotification.Action.reached_days_left,
41                    user=UserResponse.model_validate(user),
42                )
43            )