Switches production onto the hexagonal path. The legacy modules still
compile and still have tests, but nothing assembles them any more; deleting
them is the next commit, kept separate so it stays reviewable.
Composition root
----------------
`app/composition.py::build_domain_services()` is now the only place an
adapter is instantiated. It was extracted from `deps.py::langgraph_runtime`
rather than added to it: wiring there was tangled with engine startup,
orphan recovery and shutdown, so the one rule that governs it -- no SQL
backend means no service and the routes answer 503 -- could not be tested
without booting the whole application, and was held up by a single comment.
It is a pure function of already-built infrastructure, so that rule is now
an assertion. Feedback moved with it; doing this while adding schedule's
five objects costs one change instead of two.
Primary adapter
---------------
The router is protocol translation only. What is gone is the giveaway: cron
normalisation, `next_run_at` arithmetic, the re-arm rule and hand-written
ownership checks all now live in the aggregate. Domain errors map to status
codes through one table, so a new error surfaces as a 500 to be classified
rather than being swallowed by whichever `except` was nearest.
`spec_mapping` split in two (AWS's own layout puts the wire model under the
entrypoint that owns it, and a primary adapter must not import a secondary
one): `adapters/schedule/spec_column.py` for the JSON column,
`routers/schedule/spec_wire.py` for the HTTP body. The two shapes are equal
only by coincidence, so `test_schedule_spec_parity.py` runs every case
against both and compares their outputs and messages directly. Function
names differ per side so an import from the wrong one is visible.
Explicit responses
------------------
Routes returned the ORM row's `to_dict()`, leaking `user_id`,
`assistant_id`, `overlap_policy` and the two lease columns. The response
models publish exactly the field set the frontend declares -- asserted in
both directions, since an extra field is a leak and a missing one breaks a
client.
One wire detail was nearly changed by accident: Pydantic v2 serializes a UTC
datetime as `...Z`, while the legacy `coerce_iso` path emitted `+00:00`.
`UtcTimestamp` pins `isoformat()` so adopting a model does not silently
alter the wire format for every client parsing these.
Tests
-----
73 new cases: router behaviour driven through a real `ScheduleService` over
in-memory fakes (a mocked service would let the error mapping pass without
a domain error ever being raised), response shape, and the composition root.
Router mappings verified by mutation -- a wrong status code or a dropped
timezone fallback turns 9, 2 and 1 cases red respectively.
Two lifespan tests carried a `SimpleNamespace` config that predates this
change; `langgraph_runtime` now reads `config.scheduler`, so they were given
one. Tolerating the gap with `getattr` was rejected: `AppConfig.scheduler`
always exists, so the fallback would be unreachable in production and exist
purely to excuse an incomplete test double.
Full suite is back to its 24 pre-existing failures.
eb37df0779