Files
webmail-client/backend/app/plugins/db.py
T
lukasandClaude Opus 4.8 4e077f1a37 M3 plugin platform: SDK + loader, RLS-isolated tables, migrations, jobs
Backend foundation for the plugin platform (SPEC §11), Phases 1-3.

Phase 1 — SDK + loader:
- app/plugins/types.py: frozen Plugin/UiManifest/Slot/Page/JobSpec contract.
- app/plugins/sdk.py: sdk(name) facade — the only app.* import allowed for plugins
  (scoped session, plugin.{name}.* publish, blob, outbox, settings, SSRF http_get, KV, enqueue).
- app/plugins/loader.py: entry-point discovery (webmail.plugins), hook forwarding
  (API + worker), router mounting at /api/plugins/{name}, ui-manifest aggregation.
- plugin_kv core table (migration 0013) + GET /api/plugins/ui-manifest.

Phase 2 — non-removable core plugins + DB-enforced privacy:
- builtin flag (calendar/contacts will be builtin=True; uninstall refuses them).
- RLS per-user isolation on plg_* tables: least-privilege webmail_plugin role
  (migration 0014), plugin_session(user_id) sets LOCAL ROLE + app.current_user_id,
  rls.enable_rls() (ENABLE+FORCE RLS + USING/WITH CHECK policy). Mail untouched.
- Per-plugin Alembic runner (shared env, dedicated version table) + install/uninstall
  --drop-data CLI; skeleton fixture proves install -> run -> uninstall --drop-data
  leaves zero residue (§12 M3 acceptance).

Phase 3 — plugin jobs (§11.2):
- JobSpec registered as arq function plg.{plugin}.{func} + cron (5-field parser);
  singleton=True guarded by a per-(plugin,user) Redis lock; wired onto the shared
  interactive worker.

Gates: ruff, mypy --strict (94 files + tests), full suite 326 passed. RLS isolation,
migration round-trip, and singleton lock covered by tests.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Rcj3TpydMTzTSmU7kunzf8
2026-07-26 21:42:35 +02:00

45 lines
1.8 KiB
Python

"""RLS-enforced database access for plugins (SPEC §11.1 + privacy hardening).
``plugin_session(user_id)`` yields a normal SQLAlchemy session whose transaction
has been dropped to the least-privilege :data:`~app.plugins.rls.PLUGIN_ROLE` and
bound to the per-user RLS context. Both are set with transaction-local scope
(``SET LOCAL`` / ``set_config(..., is_local=true)``), so they auto-revert on
commit/rollback and cannot leak across pooled connections.
Because the role is non-superuser / non-owner / NOBYPASSRLS, the row-level policy
from :mod:`app.plugins.rls` is actually enforced: a plugin query that forgets to
filter ``user_id`` still returns only the current user's rows, and it cannot write
rows for anyone else (policy ``WITH CHECK``).
"""
from __future__ import annotations
import uuid
from collections.abc import AsyncIterator
from contextlib import asynccontextmanager
from sqlalchemy import text
from sqlalchemy.ext.asyncio import AsyncSession
from app.db import get_sessionmaker
from app.plugins.rls import PLUGIN_ROLE
@asynccontextmanager
async def plugin_session(user_id: uuid.UUID) -> AsyncIterator[AsyncSession]:
"""A transactional session scoped to ``user_id`` under RLS (SPEC §11.1)."""
async with get_sessionmaker()() as session:
try:
# Bind the RLS user context first (while still the privileged role), then
# drop into the restricted role for the rest of the transaction.
await session.execute(
text("SELECT set_config('app.current_user_id', :uid, true)"),
{"uid": str(user_id)},
)
await session.execute(text(f"SET LOCAL ROLE {PLUGIN_ROLE}"))
yield session
await session.commit()
except Exception:
await session.rollback()
raise