With a switch fitted, an AMS is not wired to a nozzle any more. It is
plumbed into one of the switch's two inlets and reaches both nozzles
through it, so every unit reports its extruder as "not fixed" (0xE) and
ams_extruder_map comes back empty on these machines.
The printer card had nothing to fall back on but the AMS unit number, so
AMS-A was badged R and AMS-B was badged L purely because their unit ids
are 0 and 1, a third unit got no badge at all, and every one of those
labels was wrong. The SpoolBuddy assign modal had the same fallback in a
worse form, mapping anything that was not extruder 1 to R.
The binding turned out to need no new telemetry. BambuStudio reads it out
of bits 24-27 of the same AMS info string we already parse for the AMS
type and the extruder id -- 0 is In-B, 1 is In-A -- and it is only
meaningful when a switch is installed, because without one 0xE really
does mean an uninitialised unit and those bits carry nothing. That gates
the read, which in turn forced the switch block to be parsed before the
AMS block: _handle_ams_data runs early in _process_message and
_update_state only much later, so the binding was lost on every frame
that carried both. _parse_fila_switch is split out and called first, and
left in _update_state as well so that stays a complete absorb step.
The badge keeps L and R rather than A and B, because the lettering is
familiar and matches the physical layout. It is a different colour from
the plain nozzle badge, and its tooltip names the inlet in full, since
the letter is the inlet's position and not a claim about which nozzle
that AMS feeds -- the switch can route either inlet to either outlet. An
AMS still reporting a real extruder id keeps its ordinary badge, which
BambuStudio also treats as authoritative over any switch binding, and a
switch that has been fitted but not yet set up on the printer shows
nothing rather than a guess.
The print dialog's slot dropdown gets the same label. It replaces a
left/right hint that never once rendered: ftsExtruderForSlot compared
snow-encoded in[] values against global tray ids and could not match.
Decoding it correctly would not have saved it -- the firmware reports
which slot sits in each inlet and which nozzle each outlet feeds, but
never which inlet is currently paired with which outlet, so no per-slot
nozzle can be derived. That function is gone rather than fixed.
The dialog also points out when every filament a print needs sits behind
one inlet. Bambu's own guidance is that this is legal but slow: a change
between two filaments on the same inlet retracts the outgoing spool all
the way back to its AMS before the next can be fed up the shared tube,
where a change across the two inlets only retracts as far as the switch.
All on one inlet means every change in the job takes the slow path, and
moving a single spool fixes it. So it advises, it does not block.
Both views update live. Two things were stopping that. fila_switch and
ams_switch_inlet were absent from printer_state_to_dict, and the frontend
shallow-merges each WebSocket push over its cached status, so a field the
push omits keeps whatever the last full fetch left behind. And the
broadcast dedup key had no term for either, so "Join IN-B" on the printer
screen moved nothing: the binding is not in the tray component of that
key, and it is not in the AMS change-hash either, which covers tray
fields only and must stay that way because it drives Spoolman sync.
Assigning an AMS to an inlet remains printer-side. BambuStudio can read
the binding and has no command to write it -- its switch class is parse
and getters only, and the recommended-arrangement popup draws and
publishes nothing -- so there is no wire format for us to copy.
Adding the two fields to PrinterState broke four test modules whose
SimpleNamespace stubs predate them. The stubs are fixed rather than the
production reads made defensive: the real dataclass always carries both,
and a getattr in the dedup key would silently stop tracking the field if
it were ever renamed.
both dialects rather than one.
Postgres upgrades never got as far as the finance schema.
database.py added on_billing_charge_failed with BOOLEAN DEFAULT 1. The 1 is a
SQLite-ism; Postgres answers DatatypeMismatchError, and _safe_execute
deliberately re-raises anything that is not an idempotency error, so
run_migrations died there and rolled the whole transaction back. No finance
tables, no columns, and the app does not start. Six lines above, the same
change gets is_voided right with an is_sqlite() branch, so this was an
oversight rather than a decision. Now branched the same way.
This also explains the four test_security.py::TestBackupKeyFiles failures
reporting "column print_archives.cost_center_id does not exist". That column's
migration exists and works -- it simply never ran, because every startup
aborted before committing. Reproduced against Postgres 16 by building a
pre-billing schema from dev and upgrading over it: fails without this,
completes with it, and re-running the migrations or starting from an empty
database are both clean.
test_billing_run_id_migration.py failed on any Postgres-configured checkout.
It builds its own SQLite engine, but run_migrations branches on the global
dialect rather than the connection in hand, so on a box whose DATABASE_URL
points at Postgres it emitted md5(random()::text) and btrim() into SQLite.
Given the same fixture test_ldap_migration.py already carries for exactly this
reason. The suite now agrees across dialects -- 9190 passed either way, where
it used to be 9184 on one and 9183 on the other.
The kill switch could not tell a print Bambuddy started from one it merely
watched.
Authorization fell back to a print_archives row in status="printing" matched on
subtask_id. But on_print_start archives every print it observes, including ones
started from Bambu Studio or Handy, and stamps them with the same status and
subtask_id -- the code says as much where it notes "a print Bambuddy didn't
dispatch". So a foreign print became authorized the moment its 3MF finished
downloading, and _active_prints was rehydrated from it, making that permanent.
The switch fired only inside the download race, and never afterwards. Neither
test caught it: one stubs the authorization call to False, the other stubs the
query to return an archive, so the real lookup was never exercised against a
foreign print.
Authorization now requires a marker Bambuddy writes itself: billing_run_id,
minted per dispatch in the scheduler, or created_by_id carried over from the
queue item. Failing that, it looks for a queue row in status="printing" on that
printer -- committed before the MQTT send, and the only durable trace a
library-file dispatch leaves, since those have no archive at send time and the
row created for them moments later carries neither marker. That row cannot be
tied to a subtask_id, so it defers rather than authorizes.
Deferring also closes a false positive the previous version shared: a restart
in the window between the send and the download left no archive at all, and a
Bambuddy print was stopped as unauthorized. Stopping a print is irreversible
and declining to act costs a log line, so ambiguity resolves that way.
Tests cover an unmarked archive not being authorization and not entering
_active_prints, either marker alone authorizing and rehydrating the fast path
without touching the queue, an unmarked archive with a live dispatch deferring,
a dispatch not yet archived deferring, and nothing at all being unauthorized.
maziggy