shopdb-flask/docs/adr/ADR-011-machines-rename.md

ADR-011: Rename the equipment domain to machines; retype the models catalog with modeltypes

• Status: ACCEPTED
• Date: 2026-07-11
• Deciders: cproudlock
• Relates to: ADR-005 (equipment vs measuringtools scope), ADR-008 (plugin migration ownership)

Context

ADR-005 split the old "equipment" concept: gage-lab instruments moved to the measuringtools plugin, leaving the equipment plugin holding exactly one thing - shop-floor machines (lathes, mills, CMMs, grinders, furnaces). The UI, the routes (/machines), the frontend view folder (views/machines/), and even the data vocabulary (asset numbers headed "MACHINE #") already said machines. Only the code identity still said equipment: the plugin name, the API prefix, the equipment/equipmenttypes tables, and the assettype='equipment' data value. Every future contributor would pay a small permanent translation tax.

A display-label-only swap was shipped first (2026-07-11) and immediately showed the dissonance: UI Machines over code equipment forever.

Separately, the legacy machinetypes table survived the Machine-model retirement for one real reason: it types the vendor models catalog (models.machinetypeid, 95 of 127 models) with fine-grained, cross-category types (Lathe, Switch, Laser Printer). Its name was a misnomer - it never typed machines specifically - and it squatted on the name the machines plugin's subtype table wants.

The economics favor doing this now and never again: the plugin contract is pre-1.0 (breaking changes are cheap per ADR-002), no sister site has adopted yet, there is no production instance, and the test suite plus CI give the strongest safety net the project has had.

Decision

Rename the domain in one coordinated pass:

Current	New	Rationale
plugins/equipment/, /api/equipment, equipment.* perms	plugins/machines/, /api/machines, machines.*	plugin identity matches the domain
equipment table, equipmentid	machines, machineid	main entity
equipmenttypes, equipmenttypeid, equipmenttype	machinetypes, machinetypeid, machinetype	subtypes take the freed name
legacy machinetypes, models.machinetypeid	modeltypes, models.modeltypeid	role-accurate: it types the models catalog, losslessly (no collapse to the 4 asset types)
assettypes.assettype = 'equipment' (data)	'machine'	the string compare sites flip with it

Migration placement follows ADR-008: the modeltypes rename and the data flips land in the core chain (core tables, core data); the plugin table renames land in the machines plugin's own chain, idempotently guarded so fresh installs (whose core chain still creates the old names at 7c04) rename on first flask plugin upgrade-all. The alembic_version_equipment version table is renamed to alembic_version_machines by the core migration so the plugin chain resumes seamlessly on existing installs. The plugin registry auto-migrates an equipment key to machines on load.

Historical migrations and accepted ADRs are not rewritten; old ids and ADR-005 wording remain as history.

Consequences

• Upgrading instances run flask db upgrade then flask plugin upgrade-all, same as every deploy; both migrations are idempotent.
• /api/equipment and equipmentApi cease to exist - a breaking change made while there is nobody to break. After contract 1.0 this class of rename would be a major-version event; this is the last cheap moment.
• The "Machine Types" settings card becomes "Model Types" and finally says what it does; the machines plugin's subtype card owns the machine-types name.
• Contributors stop translating between UI vocabulary and code vocabulary.