fix: login issue

backend/database/pg_mqtt.py

@@ -14,25 +14,13 @@ import json
 import logging
 from datetime import date, datetime, timedelta, timezone
 
-from dateutil.relativedelta import relativedelta
 from sqlalchemy import text
-from sqlalchemy.ext.asyncio import AsyncSession
-
 from config import settings
 from database.postgres import AsyncSessionLocal
 
 logger = logging.getLogger("database.pg_mqtt")
 
 
-# ---------------------------------------------------------------------------
-# Internal session helper — used by fire-and-forget insert paths that are
-# called from the MQTT ingestion thread (not inside a FastAPI request).
-# ---------------------------------------------------------------------------
-
-async def _session() -> AsyncSession:
-    return AsyncSessionLocal()
-
-
 # ---------------------------------------------------------------------------
 # Insert operations
 # ---------------------------------------------------------------------------
@@ -302,14 +290,21 @@ async def get_alerts(device_serial: str) -> list:
 # Partition management
 # ---------------------------------------------------------------------------
 
+def _add_months(d: date, months: int) -> date:
+    month = d.month - 1 + months
+    year = d.year + month // 12
+    month = month % 12 + 1
+    return d.replace(year=year, month=month, day=1)
+
+
 async def ensure_current_partitions():
     """Create device_logs partitions for the current and next month if missing."""
     async with AsyncSessionLocal() as session:
         for month_offset in (0, 1):
-            d = date.today().replace(day=1) + relativedelta(months=month_offset)
+            d = _add_months(date.today().replace(day=1), month_offset)
             partition_name = f"device_logs_{d.strftime('%Y_%m')}"
             start = d.isoformat()
-            end = (d + relativedelta(months=1)).isoformat()
+            end = _add_months(d, 1).isoformat()
             await session.execute(text(f"""
                 CREATE TABLE IF NOT EXISTS {partition_name}
                 PARTITION OF device_logs
@@ -321,7 +316,7 @@ async def ensure_current_partitions():
 
 async def drop_old_partitions(keep_months: int = 6):
     """Drop device_logs partitions older than keep_months."""
-    cutoff = date.today().replace(day=1) - relativedelta(months=keep_months)
+    cutoff = _add_months(date.today().replace(day=1), -keep_months)
     async with AsyncSessionLocal() as session:
         result = await session.execute(text("""
             SELECT tablename FROM pg_tables