Module-Rust/server/index.js

// ── The server entry point ─────────────────────────────────────────────────
//
// Core requires this file once, synchronously, while its own `app.js` is still
// being required, and calls the exported function with `(ctx, api)`. That is the
// entire server-side handshake: everything this module can reach arrives on
// `ctx`, and everything it can offer is registered through `api`.
//
// Normative: MODULE_API.md §2.2 (the entry point) and §2.4 (what you register).
//
// ── Three rules, and each one has a failure behind it ──────────────────────
//
//  1. **No `await`, and no database.** Core requires `app.js` in two build tools
//     with the connection pool pointed at a dead port — the route-manifest
//     generator and the OpenAPI generator both do it — so a module that queried
//     at registration time would hang both. Anything that needs a live database
//     goes in `onBoot`, which runs after the schema is up.
//
//  2. **Never resolve what core owns.** This module lives at
//     `<website>/modules/rust/`, outside core's `server/`, so Node's resolver
//     never reaches core's `node_modules` and `require('express')` from here
//     simply fails. express, express-validator, the database, the logger and the
//     middleware all arrive on `ctx` (§2.3) and are re-exported by `./core`. A
//     second express in the process would be a second `Router` prototype, exactly
//     as a second React would be a second renderer.
//
//  3. **Never reach into core's tree.** No relative path may escape this module's
//     root. `scripts/checkImports.js` enforces it (§5.1) and CI runs it.
//
// ── Why the requires are INSIDE the function ───────────────────────────────
//
// Every file below reaches core through `./core`, whose members resolve `ctx`
// when they are CALLED. But a router writes `const express = core.express` at its
// own file scope, and that runs the moment the file is required. So
// `core.init(ctx)` has to happen before the first `require` of anything under
// `router/`. Hoisting these to the top of the file breaks the module with an
// error about a missing `ctx`, thrown from a file that never mentions one.
//
// Node caches modules, so requiring here costs nothing after the first call.

const core = require('./core')

/**
 * @param {object} ctx  what core hands the module (MODULE_API.md §2.3), frozen
 * @param {object} api  what the module registers (§2.4)
 */
module.exports = function register(ctx, api) {
  core.init(ctx)

  /* eslint-disable global-require */
  const publicRust = require('./router/public/rust.router')
  const playerRust = require('./router/player/rust.router')
  const adminRust = require('./router/admin/rust.router')
  const usersRust = require('./router/admin/usersRust.router')
  const boot = require('./boot')
  /* eslint-enable global-require */

  const log = core.logger()

  // One prefix, on each of the three tiers (R14). The keys here must match
  // `module.json`'s `mounts` exactly — the loader compares the two and rejects a
  // mismatch in EITHER direction, so a route never declared and a prefix declared
  // and never registered both fail loudly at boot rather than quietly at runtime.
  //
  // Each router sits INSIDE its tier router, so it structurally cannot reach
  // above its prefix, and the tier's gate is already applied: `public` is behind
  // nothing by design, `admin` behind `noindex, isLoggedIn, requireRole(...)` and
  // `player` behind `noindex, requireAuth`. Per-route gates go on top; the tier
  // gate is never re-implemented.
  //
  // **Prefixes share ONE namespace with core's own, and the collision probe
  // cannot see all of it.** Core answers several public routes mounted at the
  // tier root rather than under a prefix — `/status` and `/version` among them —
  // and the loader's check cannot find those. `/rust` collides with nothing on
  // any of the three tiers, checked against core's mount tables rather than
  // assumed.
  api.registerRoutes({
    public: { '/rust': publicRust },
    player: { '/rust': playerRust },
    admin: { '/rust': adminRust },
  })

  // R13's first extension slot (§2.4). Core declares `admin.users.detail` on
  // `/api/v1/admin/users/:id` and we fill it; the router receives the parent's
  // `req.params.id` through `mergeParams`. Core's own routes on the resource are
  // declared before the slot is mounted, so core wins any path conflict — it owns
  // the user, and this module owns what it can say about one.
  //
  // **It is declared twice, in two different places, on purpose.** This call is
  // the SERVER half and `module.json`'s `extensions` array is held against it by
  // the loader. The CLIENT half is `registry.registerExtension(ID,
  // 'admin.users.detail', …)` in `entry.jsx` and must NOT appear in that array —
  // phase 1 found that the hard way with `site.footer.status`, which is a client
  // slot and fails the load outright when named there.
  api.registerExtension('admin.users.detail', usersRust)

  // The lifecycle hooks (§2.5). `onBoot` runs after core's schema, after this
  // module's schema fragment, and BEFORE the HTTP listener binds — so a module
  // that must not serve traffic until it has warmed a cache gets that for free.
  // It has no timeout, deliberately: a slow boot delays the listener, which is the
  // guarantee rather than a problem to be timed out.
  //
  // `onShutdown` runs while core's database pool and push dispatcher are still
  // open, because flushing through them is the only thing it is for. It gets a
  // five-second budget and is abandoned past it.
  api.onBoot(boot.onBoot)
  api.onShutdown(boot.onShutdown)

  // Everything else this module will register — the Team provider, the event
  // triggers and audiences, the engagement seeds, the four event catalogues, the
  // notification streams and the slash commands — is deliberately absent. Each
  // arrives with the phase that has something real to put in it. A registration
  // with nothing behind it is worse than a missing one: a declared trigger
  // nothing emits and a declared slot nothing fills are both surfaces an operator
  // can configure and then wait on.

  log.info('registered', {
    version: require('../module.json').version,
    routes: 'public:/rust player:/rust admin:/rust',
    extensions: 'admin.users.detail',
  })
}