mitlist/be/app/jobs/recurring_expenses.py
mohamad 81577ac7e8 feat: Add Recurrence Pattern and Update Expense Schema
- Introduced a new `RecurrencePattern` model to manage recurrence details for expenses, allowing for daily, weekly, monthly, and yearly patterns.
- Updated the `Expense` model to include fields for recurrence management, such as `is_recurring`, `recurrence_pattern_id`, and `next_occurrence`.
- Modified the database schema to reflect these changes, including alterations to existing columns and the removal of obsolete fields.
- Enhanced the expense creation logic to accommodate recurring expenses and updated related CRUD operations accordingly.
- Implemented necessary migrations to ensure database integrity and support for the new features.
2025-05-23 21:01:49 +02:00

119 lines
4.4 KiB
Python

from datetime import datetime, timedelta
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select, and_
from app.models import Expense, RecurrencePattern
from app.crud.expense import create_expense
from app.schemas.expense import ExpenseCreate
import logging
from typing import Optional
logger = logging.getLogger(__name__)
async def generate_recurring_expenses(db: AsyncSession) -> None:
"""
Background job to generate recurring expenses.
Should be run daily to check for and create new recurring expenses.
"""
try:
# Get all active recurring expenses that need to be generated
now = datetime.utcnow()
query = select(Expense).join(RecurrencePattern).where(
and_(
Expense.is_recurring == True,
Expense.next_occurrence <= now,
# Check if we haven't reached max occurrences
(
(RecurrencePattern.max_occurrences == None) |
(RecurrencePattern.max_occurrences > 0)
),
# Check if we haven't reached end date
(
(RecurrencePattern.end_date == None) |
(RecurrencePattern.end_date > now)
)
)
)
result = await db.execute(query)
recurring_expenses = result.scalars().all()
for expense in recurring_expenses:
try:
await _generate_next_occurrence(db, expense)
except Exception as e:
logger.error(f"Error generating next occurrence for expense {expense.id}: {str(e)}")
continue
except Exception as e:
logger.error(f"Error in generate_recurring_expenses job: {str(e)}")
raise
async def _generate_next_occurrence(db: AsyncSession, expense: Expense) -> None:
"""Generate the next occurrence of a recurring expense."""
pattern = expense.recurrence_pattern
if not pattern:
return
# Calculate next occurrence date
next_date = _calculate_next_occurrence(expense.next_occurrence, pattern)
if not next_date:
return
# Create new expense based on template
new_expense = ExpenseCreate(
description=expense.description,
total_amount=expense.total_amount,
currency=expense.currency,
expense_date=next_date,
split_type=expense.split_type,
list_id=expense.list_id,
group_id=expense.group_id,
item_id=expense.item_id,
paid_by_user_id=expense.paid_by_user_id,
is_recurring=False, # Generated expenses are not recurring
splits_in=None # Will be generated based on split_type
)
# Create the new expense
created_expense = await create_expense(db, new_expense, expense.created_by_user_id)
# Update the original expense
expense.last_occurrence = next_date
expense.next_occurrence = _calculate_next_occurrence(next_date, pattern)
if pattern.max_occurrences:
pattern.max_occurrences -= 1
await db.flush()
def _calculate_next_occurrence(current_date: datetime, pattern: RecurrencePattern) -> Optional[datetime]:
"""Calculate the next occurrence date based on the pattern."""
if not current_date:
return None
if pattern.type == 'daily':
return current_date + timedelta(days=pattern.interval)
elif pattern.type == 'weekly':
if not pattern.days_of_week:
return current_date + timedelta(weeks=pattern.interval)
# Find next day of week
current_weekday = current_date.weekday()
next_weekday = min((d for d in pattern.days_of_week if d > current_weekday),
default=min(pattern.days_of_week))
days_ahead = next_weekday - current_weekday
if days_ahead <= 0:
days_ahead += 7
return current_date + timedelta(days=days_ahead)
elif pattern.type == 'monthly':
# Add months to current date
year = current_date.year + (current_date.month + pattern.interval - 1) // 12
month = (current_date.month + pattern.interval - 1) % 12 + 1
return current_date.replace(year=year, month=month)
elif pattern.type == 'yearly':
return current_date.replace(year=current_date.year + pattern.interval)
return None