Commit Graph
3 Commits
Author SHA1 Message Date
Chris CoutinhoandClaude Opus 4.7 51419329b0 fix(storage): address PR #798 round-3 review (SonarQube + pool sizing + RETURNING test)
Round-3 fixes. Two threads:
- 9 OPEN SonarQube issues caused the "E Security Rating on New Code"
  gate failure. The bot's diagnosis (sa.text(text_sql) → SQL injection)
  was a wrong guess; the actual SQ rules firing were different.
- Bot's substantive concerns: pool defaults too aggressive,
  delete_browser_session RETURNING path untested on Postgres,
  schema_version legacy table created on Postgres, stale module
  docstring.
- User's underlying question on the pool: "isn't 1 connection enough?"
  Right-sized to 2+5 and documented the concurrency model in ADR-026
  so the rationale is durable.

SonarQube quality-gate fixes (clears all 9 OPEN issues)
-------------------------------------------------------
- BLOCKER S6418: rename `SECRET` constant in test_storage_logging.py
  to `SENTINEL_PASSWORD_FRAGMENT` + NOSONAR with rationale.
- CRITICAL S3776: extract `_build_postgres_engine()` from
  `initialize()` (was complexity 26 > 15); incidentally creates a
  clean unit-test seam for engine args.
- CRITICAL S4423: `ssl.create_default_context(cafile=...)` is flagged
  as "weak protocol" — Python 3.10+ already negotiates the strongest
  available protocol. Explicitly pass `purpose=ssl.Purpose.SERVER_AUTH`
  and NOSONAR with the Python-version rationale.
- MAJOR S3358: split the TLS-mode nested ternary in the engine
  factory into a `_describe_ssl_arg()` helper.
- MAJOR S2068 ×3: bind test app-password literals to local vars and
  put `# NOSONAR S2068` on the same line as the literal (anchoring
  requirement) instead of on the closing paren.
- MINOR S7503 ×2: `# NOSONAR S7503` on `_Cursor.__aenter__/__aexit__`
  — they MUST be `async` per the context-manager protocol.

Pool sizing right-sized (answers "why so many connections?")
------------------------------------------------------------
- `DATABASE_POOL_SIZE` default 10 → **2**.
- `DATABASE_MAX_OVERFLOW` default 20 → **5**.
- Per-pod max drops from 30 to 7. With 3 replicas, total = 21
  connections (was 90) — well under managed-Postgres
  `max_connections=100`.
- New INFO log at startup: `Postgres engine ready: pool_size=N
  max_overflow=M (per-pod max K connections)`. Surfaces the active
  sizing without grepping config.
- New ADR-026 § "Concurrency model and pool sizing" explains
  asyncpg's single-flight connection semantics, the MCP workload
  shape (read-mostly point lookups), why-not-1 (multi-user
  serialization), and the tune-up/tune-down recipe.
- `docs/configuration.md` table updated with new defaults +
  homelab-vs-prod tuning guidance, linking the ADR.

RETURNING path covered on Postgres
----------------------------------
- New `test_browser_session_delete_returning` exercises the
  `DELETE … RETURNING user_id` path — the only RETURNING clause in
  the storage layer and the most dialect-sensitive SQL in this PR.
  Asserts both present-row (returns True, row gone) and absent-row
  (returns False) branches.

Schema portability polish
-------------------------
- `alembic 001`: gate `schema_version` table creation on
  `op.get_bind().dialect.name == "sqlite"`. The table exists purely
  to match the fingerprint of pre-Alembic SQLite databases; fresh
  Postgres installs no longer carry the dead legacy table.

Misc polish
-----------
- Module docstring: "SQLite-based" → "SQL-backed", with a sentence
  on the DATABASE_URL opt-in and an ADR-026 link.
- Comment on `_wrap_row` noting `row._mapping` is the documented
  RowMapping accessor in SQLAlchemy 2.x despite the underscore.

Skipped (rationale in PR reply)
-------------------------------
- `_qmark_to_named` SQL-comment handling: docstring already notes
  the limitation; no `?` in storage SQL comments today.
- Module-level `anyio.Lock()`: established precedent confirmed by
  the bot itself.
- `get_audit_logs` `SELECT *`: pre-existing pattern, out of scope.

Verification
------------
- `uv run pytest tests/unit/` — 1025 passed.
- `TEST_DATABASE_URL=… uv run pytest tests/integration/test_storage_postgres.py -m postgres` — 7 passed.
- `ruff check && ruff format --check && ty check` — clean.
- Confirmed `schema_version` absent on fresh Postgres, still present
  on fresh SQLite.

Tracked on Astrolabe Cloud POC board, card #99.

---

_This PR was generated with the help of AI, and reviewed by a Human_

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-16 19:33:23 +02:00
Chris CoutinhoandClaude Opus 4.7 f2b7bf132f fix(storage): address PR #798 review feedback (credentials, asyncpg extra, TLS, pool)
Round-2 fixes after the bot review on PR #798 plus two user follow-ups
(self-signed Postgres support; asyncpg should be a PyPI extra). Folded
into the same PR rather than a follow-up since the work is still
unmerged.

Security
--------
- Mask database credentials in all 5 log call sites (storage.py × 4,
  migrations.py × 1) via a new `mask_db_password()` helper in config.py.
  Uses SQLAlchemy's `make_url(...).render_as_string(hide_password=True)`
  with a regex fallback so the masking path never raises.
- New `tests/unit/test_storage_logging.py` asserts a sentinel password
  never appears in `caplog` during `RefreshTokenStorage.initialize()`.

Distribution
------------
- `asyncpg` moved to `[project.optional-dependencies] postgres` so a
  vanilla `pip install nextcloud-mcp-server` no longer pulls in the
  ~5 MB C extension. The Docker image runs `uv sync --extra postgres`,
  so containerized deployments are unchanged.
- When `DATABASE_URL=postgresql+asyncpg://...` is set on a venv missing
  the extra, `RefreshTokenStorage.initialize()` raises a friendly
  RuntimeError pointing at `[postgres]` rather than the generic
  ModuleNotFoundError.

TLS for the Postgres backend
----------------------------
- New `DATABASE_VERIFY_SSL` + `DATABASE_CA_BUNDLE` env vars mirror the
  existing `NEXTCLOUD_VERIFY_SSL` / `NEXTCLOUD_CA_BUNDLE` pattern
  (validators in Settings.__post_init__, `get_database_ssl()` helper
  alongside `get_nextcloud_ssl_verify()`). `DATABASE_VERIFY_SSL=false`
  wins over `DATABASE_CA_BUNDLE` for incident-response convenience.
- Default is **None** rather than True — keeps PR #798's behavior
  intact for cluster-internal Postgres that runs without TLS. Operators
  opt into verify-full or supply a private CA. ADR-026 records the
  reasoning vs the Nextcloud HTTPS default.
- Engine factory in `storage.py` passes `ssl` via `connect_args` only
  when `get_database_ssl()` returns non-None; otherwise asyncpg's
  default (`prefer`) applies.
- Storage logs which TLS mode is active at INFO (no secret material).

Configurable connection pool
----------------------------
- `DATABASE_POOL_SIZE` (default 10) and `DATABASE_MAX_OVERFLOW`
  (default 20) replace the hardcoded engine values. With many replicas
  this can blow past managed-Postgres `max_connections=100`; tune down
  for large fleets.
- gte-1 / gte-0 validators in __post_init__ reject 0/negative pool
  sizes at startup with the offending value in the error.

Consistency polish
------------------
- Migration 006: convert raw `op.execute("ALTER TABLE ... ADD COLUMN")`
  to `op.batch_alter_table(...).add_column(sa.Column("nonce", sa.Text))`
  for stylistic consistency with the rewritten 001-005. Downgrade now
  drops the column instead of being a no-op.
- `registered_webhooks.created_at` standardized from `sa.Float` to
  `sa.BigInteger` (all other `*_at` columns); `store_webhook()` casts
  `time.time()` → `int`.
- `is_sqlite_url()` made case-insensitive.

Testing
-------
- New `tests/integration/test_storage_postgres.py::test_cleanup_expired_roundtrip`
  exercises `cleanup_expired_tokens`, `cleanup_expired_sessions`, and
  `cleanup_expired_browser_sessions` — relies on DELETE rowcount,
  historically dialect-tricky.
- `tests/unit/test_ssl_config.py` extended with `TestDatabaseSSLSettings`
  + `TestGetDatabaseSSL` classes (9 new tests) mirroring the existing
  Nextcloud SSL tests one-for-one.

Docs
----
- `docs/configuration.md` Centralized-Storage section grew the four new
  env vars + a homelab example with a private CA.
- `docs/ADR-026` grew Distribution, TLS, and `alembic/env.py` async-pattern
  subsections explaining the non-obvious design choices.

Helm chart counterpart in cbcoutinho/helm-charts PR #34 (separate
commit on `feat/nextcloud-mcp-server-database-url`).

Verification
------------
- `uv run pytest tests/unit/` — 1025 passed.
- `TEST_DATABASE_URL=... uv run pytest tests/integration/test_storage_postgres.py -m postgres` — 6 passed (including new cleanup test).
- `uv run ruff check && uv run ruff format --check && uv run ty check -- nextcloud_mcp_server` — clean.

Tracked on Astrolabe Cloud POC board, card #99.

---

_This PR was generated with the help of AI, and reviewed by a Human_

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-16 18:53:45 +02:00
Chris CoutinhoandClaude Opus 4.7 292cbb3292 feat(storage): pluggable database backend via DATABASE_URL (ADR-026)
Adds a `DATABASE_URL` setting that lets `RefreshTokenStorage` run against
any SQLAlchemy async backend, primarily `postgresql+asyncpg://...` for
HA k8s deployments. Default behavior is unchanged: when `DATABASE_URL` is
unset the server falls back to the existing `TOKEN_STORAGE_DB` path /
ephemeral SQLite tempfile.

Why
---
Today every MCP pod needs its own PVC to hold the SQLite file, which
pins the Deployment to one replica and blocks horizontal scaling. With
this change, operators can point all replicas at a shared Postgres
(CNPG, RDS, etc.) and the pods become stateless. Encryption stays in
Python (Fernet); the database only sees ciphertext.

What changed
------------
- `config.get_database_url()` resolves DATABASE_URL → TOKEN_STORAGE_DB →
  ephemeral tempfile in that priority order.
- `RefreshTokenStorage` builds a process-shared `AsyncEngine` in
  `initialize()`. SQLite gets NullPool; Postgres gets pool_size=10,
  max_overflow=20, pool_pre_ping=True. 30 aiosqlite call sites adapted
  via a thin `_DBConn` / `_Cursor` / `_Row` / `_ExecuteCtx` shim so
  existing method bodies need no churn beyond the connection
  context-manager swap.
- 7 `INSERT OR REPLACE` statements rewritten as portable
  `INSERT ... ON CONFLICT (...) DO UPDATE` (SQLite ≥ 3.24, Postgres ≥ 9.5).
- `sqlite_master` legacy-detection lookup replaced with SQLAlchemy
  inspector so the path works against either backend.
- File-permission hardening + parent-dir creation gated on
  `is_sqlite_url(...)` — centralized backends manage their own filesystem.
- Alembic migrations 001/002/003/005 converted from raw `op.execute(SQL)`
  to portable `op.create_table()` / `op.create_index()` with SQLAlchemy
  types. All timestamp columns are `sa.BigInteger` so Postgres allocates
  BIGINT (unix epochs don't fit in INT4). SQLite treats BIGINT as
  INTEGER, so existing deployments at revision 006 see no schema drift.
- `migrations.py` + CLI take URLs; `db {upgrade,downgrade,current,history}`
  gain `--database-url / -u` alongside the legacy `--database-path / -d`.
  `get_current_revision()` uses SQLAlchemy inspector instead of raw
  sqlite3, so the CLI works against Postgres too.
- `docker-compose.yml` adds a `postgres-test` service under the
  `postgres` profile (pinned `postgres:16-alpine` digest) for
  integration testing.
- Unit storage tests parametrized over backends via shared
  `tests/fixtures/storage_backend.py` — every test in
  `test_app_password_storage.py` and `test_webhook_storage.py` runs
  once per backend that is available. Postgres is opted in by
  `TEST_DATABASE_URL`.
- New `tests/integration/test_storage_postgres.py` (5 tests, marked
  `postgres` + `integration`) covers refresh-token, app-password,
  OAuth-session, webhook, and audit-log paths end-to-end on Postgres.
- New `docs/ADR-026-pluggable-database-backend.md` records the decision;
  `docs/configuration.md` documents `DATABASE_URL` with examples.

Out of scope
------------
- No SQLite → Postgres data migration tool (clean cutover; tokens reissue
  on next login, webhooks re-register on next sync tick).
- This repo does not provision Postgres. The matching helm chart change
  lives in cbcoutinho/helm-charts (database.url / existingSecret values).

Verification
------------
- `uv run pytest tests/unit/` — 1012 passed, SQLite path unchanged.
- `docker compose --profile postgres up -d postgres-test`
- `TEST_DATABASE_URL=... uv run pytest tests/integration/test_storage_postgres.py -m postgres -v`
  — 5 passed.
- `TEST_DATABASE_URL=... uv run pytest tests/unit/test_app_password_storage.py
  tests/unit/test_webhook_storage.py` — 50 passed (25 per backend).
- `uv run ruff check && uv run ruff format --check && uv run ty check -- nextcloud_mcp_server` — clean.

Tracked on Astrolabe Cloud POC board, card #99.

---

_This PR was generated with the help of AI, and reviewed by a Human_

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-16 18:06:42 +02:00