# ADR-015: Where a site's own data is allowed to live

- Status: ACCEPTED
- Date: 2026-08-11
- Deciders: cproudlock
- Relates to: ADR-004 (per-site instances, not multi-tenant), ADR-013 (plugin catalog + lean per-site builds), ADR-014 (schema-lean per-site builds)

## Context

ShopDB is built as a product several GE Aerospace sites can adopt (ADR-004:
each site runs its own instance). It is also developed at one site, West
Jefferson, against that site's live fleet. Every feature therefore arrives
carrying that site's hostnames, networks, share paths and vocabulary, and the
fastest way to ship any of them is to write the value where the code needs it.

That is not a hypothetical drift. A scan of `plugins/` and `shopdb/` for a site
host, a site FQDN or a site network returns 19 hits, of which roughly 8 are a
shipped default or a hardcode rather than a comment:

- `plugins/geenforce/seed_display_scope.py` bakes `https://tsgwp00525.wjs.
  geaerospace.net/shopdb` and `device.geaerospace.net` into an inline PowerShell
  payload. A sister site cannot override either without editing the source.
- `plugins/backups/services/registry.py` defaults the backup share root to a WJ
  UNC path.
- `shopdb/core/api/settings.py` ships `device.geaerospace.net` and
  `Printer-{ip}.printer.geaerospace.net` as SETTING DEFAULTS, so another site
  inherits WJ's domain silently until someone notices.
- `shopdb/core/models/dashboarddefault.py` holds the same domain a second time
  as a module constant, and `plugins/computers/api/routes.py` a third time as a
  literal fallback.

The problem is not that site-specific values exist - they must. It is that the
repository already has three good mechanisms for them and no rule about which to
use, so each new value lands wherever was convenient. The result reads as drift
because it is unmanaged, not because any single choice was wrong.

Nothing here is a security matter: these are internal hostnames on an air-gapped
network, and `tests/test_docs_publishable.py` already gates what reaches the
public wiki. This is about whether a sister site can adopt the product without
reading our source.

## Decision

A site's own data lives in one of three places, in this order of preference.

**1. A setting, with a NEUTRAL default.** Anything an operator could plausibly
change: hostnames, domains, share paths, networks, base URLs, label prefixes.
The default that ships must be blank or generic, never one site's value. Blank
must be a working state - code reads the setting and degrades sensibly, the way
`display_fqdn_domain` already treats blank as "use the hostname as-is". A
site-specific default is the failure mode this ADR exists to stop: it is
invisible, it looks deliberate, and it is wrong everywhere except here.

**2. A site-namespaced directory.** Anything that is genuinely one site's and
will never be another's, such as the West Jefferson import loader at
`scripts/site_imports/wjf/`. Never reached by another site's build.

**3. Seed data, not code.** Vocabularies and catalogs, loaded by `flask seed`
and editable per site afterwards.

Fleet-wide convention is NOT site-specific. The `gea-shopfloor-*` imaging types
are a GE fleet taxonomy, not one site's data, and they already carry a per-site
override through the `pctypemap_*` settings. They are out of scope here.

Comments and documentation may name a site where it explains WHY - "part markers
share a machine number at West Jefferson" is a fact a maintainer needs. Prefer
phrasing the rule generally and the example specifically.

## Enforcement

`scripts/check-naming-and-style.sh`, which already runs in CI, greps `plugins/`
and `shopdb/` for a site host, a site FQDN or a site network, excluding tests
and `site_imports/`.

It ships in REPORT-ONLY mode. It prints findings and does not fail the build,
because turning a 19-item backlog into a hard gate on the day it lands blocks
every unrelated commit until someone works through it. Set
`SITE_LITERALS_ENFORCE=1` to make it a gate; do that once the real hardcodes
below are cleared.

## Consequences

Positive:

- A sister site can adopt without reading our source for values it must change.
- The backlog is visible and counted rather than felt.
- New site-specifics are caught at commit time, in the same place the naming
  rules are already enforced, so there is nothing new to remember.

Negative:

- Report-only means the rule is advisory until someone flips it, and an
  advisory rule can be ignored.
- A neutral default is more code than a working one: every read needs a blank
  case, which is a real cost paid at every call site.
- The pattern list is a denylist and will miss a site value it has not been
  taught. It catches drift, not everything.

## Backlog

Real hardcodes and site-specific defaults, to clear before enforcing:

- `plugins/geenforce/seed_display_scope.py` - kiosk base URL, FQDN domain, and
  the legacy-shortcut sweep pattern
- `plugins/backups/services/registry.py` - `DEFAULTSHAREROOT`
- `shopdb/core/api/settings.py` - `display_fqdn_domain` and the printer
  hostname pattern defaults
- `shopdb/core/models/dashboarddefault.py` - `DEFAULT_DISPLAY_FQDN_DOMAIN`
- `plugins/computers/api/routes.py` - literal fallback duplicating that default

The domain appears three times in three files, which is its own defect: one
setting, one default, one read.

Cosmetic mentions in comments and UI placeholder text are acceptable under this
ADR and are not part of the backlog, with one exception worth fixing when
convenient: the GE-Enforce settings page shows WJ's real CIDRs as its
placeholder, which every site sees.
