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>
The CalDAV REPORT in `_search_events_by_date` unconditionally requested
server-side `<C:expand>`. Per RFC 4791 §9.6.5 the server then normalizes
every expanded DTSTART/DTEND to UTC `Z`, which destroyed two pieces of
information on the read path:
- RFC 5545 floating local times came back as fake-UTC (a `+00:00` suffix
that did not match the stored value), so a 2:30 PM floating event was
indistinguishable from a 14:30 UTC event in the MCP response.
- TZID-bound events lost their IANA TZID context — a "10am America/New_York"
event came back as `14:00:00+00:00`, making it impossible for callers to
reconstruct DST-aware recurrence semantics.
Replace `<C:expand>` with client-side recurrence expansion via the
`recurring-ical-events` library (promoted from transitive to direct dep),
so the wire response retains its original DTSTART format. Surface the
TZID parameter as new `start_tz`/`end_tz` fields on `CalendarEventSummary`.
Add an optional `timezone` (IANA name) parameter to `nc_calendar_create_event`
and `nc_calendar_update_event` so callers can pin a TZID for naive input;
the helper attaches `ZoneInfo(...)` and emits a paired `VTIMEZONE`
component. Naive input without `timezone` continues to store as RFC 5545
floating local time (with a warning logged). Offset-aware input continues
to store as UTC `Z`.
Drive-by: switch the update path's DTSTART/DTEND assignment from raw
`datetime` to `vDDDTypes(dt)` wrappers — the previous code produced invalid
iCal like `DTSTART:2026-05-14 10:00:00+00:00` for any TZ-aware update.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds a hosted Mistral embedding option (mistral-embed, 1024-dim) alongside
the existing Bedrock / OpenAI / Ollama / Simple providers. Implementation
mirrors OpenAIProvider: lazy dimension detection with a known-models lookup,
chunked batch requests, defensive index sort, and a 429-aware retry decorator.
In the same change, ProviderRegistry switches from os.getenv to the
dynaconf-backed Settings dataclass so all five providers share a single
configuration path. config.py gains the previously-uncovered Bedrock keys,
the new Mistral keys, the missing OPENAI_GENERATION_MODEL /
OLLAMA_GENERATION_MODEL, and SIMPLE_EMBEDDING_DIMENSION.
Auto-detection priority: Bedrock → OpenAI → Mistral → Ollama → Simple.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
pymupdf-layout is Artifex commercial-only proprietary (its wheel ships
only a one-line COPYING noting "Commercial license. See artifex.com"),
incompatible with the project's AGPL build. It was declared as a runtime
dependency but unused: not imported anywhere in nextcloud_mcp_server/ or
tests/.
Also drop tools/parse-doc.py, an unused dev scratch script that was the
only caller of pymupdf.layout.activate(). Per the explicit warning in
document_processors/pymupdf.py, activating layout breaks
pymupdf4llm.to_markdown(page_chunks=True) per pymupdf4llm#323.
Closes#725
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>