Document task DB access and unify background task DB handling

backend/app/tasks/geo_re_resolve.py

@@ -21,18 +21,16 @@ from typing import TYPE_CHECKING
 
 import structlog
 
-from app.db import open_db
+from app.services import geo_service
+from app.tasks.db import task_db
 from app.utils.runtime_state import get_effective_settings
 
 if TYPE_CHECKING:
-    import aiosqlite
     from aiohttp import ClientSession
-    from app.config import Settings
-from app.services import geo_service
-
-if TYPE_CHECKING:
     from fastapi import FastAPI
 
+    from app.config import Settings
+
 log: structlog.stdlib.BoundLogger = structlog.get_logger()
 
 #: How often the re-resolve job fires (seconds).  10 minutes.
@@ -42,21 +40,14 @@ GEO_RE_RESOLVE_INTERVAL: int = 600
 JOB_ID: str = "geo_re_resolve"
 
 
-async def _get_db(settings: "Settings") -> tuple[aiosqlite.Connection, bool]:
-    db = await open_db(settings.database_path)
-    return db, True
-
-
-async def _run_re_resolve_with_resources(settings: "Settings", http_session: "ClientSession") -> None:
+async def _run_re_resolve_with_resources(settings: Settings, http_session: ClientSession) -> None:
     """Query NULL-country IPs from the database and re-resolve them.
 
     Args:
         settings: The resolved application settings used for database access.
         http_session: The shared aiohttp session used for external lookups.
     """
-    db, close_db = await _get_db(settings)
-
-    try:
+    async with task_db(settings) as db:
         # Fetch all IPs with NULL country_code from the persistent cache.
         unresolved_ips = await geo_service.get_unresolved_ips(db)
 
@@ -73,17 +64,14 @@ async def _run_re_resolve_with_resources(settings: "Settings", http_session: "Cl
         # passed.  This is a background task so DB writes are allowed.
         results = await geo_service.lookup_batch(unresolved_ips, http_session, db=db)
 
-        resolved_count: int = sum(
-            1 for info in results.values() if info.country_code is not None
-        )
-        log.info(
-            "geo_re_resolve_complete",
-            retried=len(unresolved_ips),
-            resolved=resolved_count,
-        )
-    finally:
-        if close_db:
-            await db.close()
+    resolved_count: int = sum(
+        1 for info in results.values() if info.country_code is not None
+    )
+    log.info(
+        "geo_re_resolve_complete",
+        retried=len(unresolved_ips),
+        resolved=resolved_count,
+    )
 
 
 async def _run_re_resolve(app: FastAPI) -> None: