Admin Feature Flags & Navigation Visibility

An admin-only control surface for feature flags (named on/off switches) and per-page navigation visibility (hide or disable nav links across the site). It is persisted, applies on every page, and is enforced both in the browser and on the server.

Access: the config page and all write APIs are admin-only. On the local dev server (port 4178) and on a loopback connection with LANTERN_LOCAL_ADMIN=1, the owner is treated as admin automatically. Remote users need the admin role.

The config page — `/admin-flags.html`

Open Admin → Feature Flags (the Admin link appears in the nav only for admins). The page has two sections:

Each navigable page has two independent toggles:

Toggle	Effect on the nav link	Effect on the page itself
Hidden	Link removed from the nav	Page still reachable by direct URL
Disabled	Link greyed out, un-clickable, tooltip	Page blocked for non-admins (admins keep preview access)

Use Hidden to tidy the nav; use Disabled as a temporary kill-switch for a page you want taken out of service.

Feature flags

Add a flag (key + optional label/description), toggle it on/off, or delete it. Keys are normalized to lowercase a–z 0–9 . _ - (e.g. New Dashboard! → newdashboard).

Using a feature flag

Flags are exposed to every page through auth-gate.js. Two ways to consume them:

1. Declarative — show/hide elements by flag:




<div data-flag="beta_banner">🎉 Beta features are live</div>





<div data-flag-off="beta_banner">Coming soon</div>

2. Imperative — check in JavaScript:


if (window.LanternFlags && window.LanternFlags.enabled('beta_banner')) {

  // …enable the beta code path

}

// or listen for readiness:

document.addEventListener('lantern-flags-ready', (e) => {

  console.log(e.detail.flags); // { beta_banner: true, … }

});

Server-side, use isFlagEnabled('beta_banner') from lib/feature-flags.js.

How it's wired

Store: apps/lantern-garage/lib/feature-flags.js — persists to

data/admin/feature-flags.json (cached, latest-wins). Holds the flag map and a per-page { hidden, disabled } navigation map. The canonical nav page list lives in NAV_PAGES and must stay in step with the links in each page's nav.

Client wiring: apps/lantern-garage/public/js/auth-gate.js (loaded on every

page) fetches the config and applies it by link href, so it covers each page's inline <nav class="site-nav"> automatically — not a single header component. It also injects the Admin link for admins, reusing the session it already fetches.

Server enforcement: apps/lantern-garage/routes/pages.js blocks any page

flagged Disabled for non-admins (returns a friendly "temporarily disabled" page; admins still get through for preview).

API reference

Public reads (consumed by the client on every page):

Method	Path	Returns
`GET`	`/api/flags`	`{ flags: { key: enabledBool } }`
`GET`	`/api/nav-config`	`{ navigation: { path: { hidden, disabled } } }`

Admin-only (403 for non-admins):

Method	Path	Body	Action
`GET`	`/api/admin/config`	—	Full config (flags + navigation, with metadata)
`PUT`	`/api/admin/flags`	`{ key, label?, description?, enabled? }`	Create/update a flag
`DELETE`	`/api/admin/flags/:key`	—	Remove a flag
`PUT`	`/api/admin/nav`	`{ path, hidden?, disabled? }`	Set a page's nav visibility

Example — disable the Trader nav link as a kill-switch:


curl -X PUT http://127.0.0.1:4178/api/admin/nav \

  -H 'Content-Type: application/json' \

  -d '{"path":"/trader-dashboard.html","disabled":true}'

Notes

Hidden ≠ secured. Hiding a link only removes it from the nav; the page stays

reachable by URL. Use Disabled (server-enforced) or a role/entitlement gate in routes/pages.js when access must actually be restricted.

Flag and nav state are runtime data (data/admin/feature-flags.json), not code —

changes take effect immediately, no deploy required.