station-master-startos/README.md

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  <img src="icon.png" alt="Station Master Logo" width="21%">
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# Station Master on StartOS

> Everything not listed in this document should behave the same as upstream
> Station Master. If a feature, setting, or behavior is not mentioned here,
> the upstream documentation is accurate and fully applicable — see the
> Documentation section of `instructions.md` for links.

Station Master is a railroad operations board game with an authoritative multiplayer server;
solitaire needs no server and is not what this package is for. This package runs that server —
the browser client, the lobby, and the intent/SSE API — as a single StartOS service.

**Bundled version: 0.7.1.** Four playtest fixes on top of 0.7.0. An empties-only train may couple a
caboose again (a caboose carries the crew, so it is never a load); the end of a Day is a modal
carrying the standings, the Days left and the combined target, because a Day turns over inside the
automatic phases and used to pass unremarked; a Timetabled train may be discarded to a Department
pile for a rival to pick up, governed by a new `discardTimetabled` New Game setting that is on by
default, while an Extra never may; and a blocked passenger platform now reports its reason — the
coach shortage behind Gitea#2 is a ruled-in part of the game, and what was actually broken was the
silence. **Games in progress survive this update**: all three engine-visible changes only WIDEN what
is legal, so every intent a 0.7.0 game recorded still replays, and the server resumes a save by
replaying it rather than by comparing version strings.

0.7.0 remains the shape of the service: the lobby sets a game up from one of four game types
(Solitaire, Co-op, Competitive, Cutthroat) plus Custom, offers the whole rule set for reading before
a seat is taken, and lets a player leave a lobby or a running game and come back to it. None of this
changes anything the package itself does: the submodule pin is the version, and the service is the
same server it always was.

---

## Table of Contents

- [Image and Container Runtime](#image-and-container-runtime)
- [Volume and Data Layout](#volume-and-data-layout)
- [File Models](#file-models)
- [Dependencies](#dependencies)
- [Network Access and Interfaces](#network-access-and-interfaces)
- [Installation and First-Run Flow](#installation-and-first-run-flow)
- [Actions](#actions)
- [Tasks](#tasks)
- [Health Checks](#health-checks)
- [Backups and Restore](#backups-and-restore)
- [Limitations and Differences](#limitations-and-differences)
- [Quick Reference for AI Consumers](#quick-reference-for-ai-consumers)

---

## Image and Container Runtime

Built from source with a custom `Dockerfile` — there is no published Station Master image.

| What to Document | Value |
| --- | --- |
| Image source | Custom multi-stage `Dockerfile`: `node:*-slim` builder runs `npm run build:web` to produce the static client, then a second `node:*-slim` stage copies only `package.json`, `src/`, and the built `dist/` — no `node_modules` in the runtime stage, since the server has zero runtime dependencies |
| Architectures | x86_64, aarch64 |
| Entrypoint | `node src/server/index.ts` — runs straight from TypeScript source; no compile step, see Limitations |

One subcontainer: `station-master-sub`, running the single daemon `server`.

## Volume and Data Layout

One volume, `data`, mounted at `/data` (`DATA_DIR`).

| What to Document | Value |
| --- | --- |
| Volume names | `data` |
| Mount points | `/data` |
| StartOS files | `store.json` — holds the join and admin secrets (see File Models) |
| Database | None — flat files. The server holds any number of games at once: each is `games/<gameId>/game.json` (`{ engineVersion, seed, config, playerNames, history, status, createdAt, lastMoveAt, botSeats }`) plus `turn-timings.json`, with a top-level `index.json` naming every game and lobby state for those not yet started |

## File Models

One StartOS-managed file, `store.json`, on the `data` volume.

- **`store.json`** — JSON, holding two independent secrets, both seeded on install by
  `init/generateSecrets.ts` and both read reactively by `main.ts`, so rewriting either restarts the
  daemon with the new value.
  - `joinSecret` — 24 characters. What players need to create or join a game. The daemon will not
    start without one, so it is never left unset. Rewritten only by the **Get Join Secret**
    action, which mints a new value on every run.
  - `adminSecret` — 32 characters. Gates the server's `/api/games` routes, which the two game
    actions use. **Deliberately not the join secret**: every player holds that one, so gating a
    delete with it would let anyone at the table destroy anyone else's game. It is never shown to
    a player and never leaves the package except as the daemon's `ADMIN_SECRET`. Backfilled on
    update for a volume written before this field existed, and otherwise never rewritten.

  Neither key is re-asserted on start, so a hand edit to either survives until the relevant action
  is next run.

Everything else under `/data` — `games/`, `index.json`, lobby and session state — is the
application's own persistence, written directly by the server process, not by a StartOS file
model.

## Dependencies

None.

## Network Access and Interfaces

One interface, `ui`, on the single port the daemon listens on. It serves the browser client, the
lobby and intent HTTP API, and the per-seat SSE game stream — all from the same origin, which is
what lets a player reach the server from a LAN address and another player reach it from a
different one in the same game.

## Installation and First-Run Flow

No setup wizard. On install, both secrets are generated and stored immediately (see File Models),
and a critical task is raised pointing at **Get Join Secret** — the service starts and is usable
the moment the daemon is healthy, but a player cannot create or join a game until the join secret
has been retrieved and shared with them.

**Updating the package keeps games in progress, unless the rules actually changed.** On boot the
server replays each saved game's moves through the current engine and resumes it if they all still
apply — the version that wrote the file is recorded and reported but decides nothing. When a move
*is* rejected, that game is refused and the log names it: `move 3 of 8 (localOps.choose) is
rejected by the current rules with OPTION_ALREADY_CHOSEN`. A refused game is never modified or
deleted, so reinstalling the previous version makes it loadable again and it can be played out.

Earlier versions of this package compared version strings instead, which destroyed every game in
progress on every update, including updates that changed only how the board is drawn.

## Actions

Two of the three read or change the games on the server, and both are `only-running`: what they
report exists only inside the live server process. A save is a seed plus a list of moves, so
"whose turn is it" is answerable only by replaying the game through the engine — which lives in
the game repo, not in this package. The server has already done that work and is asked for the
answer.

- **Get Join Secret** (`get-join-secret`) — run this any time you want to read the current join
  secret, or to invalidate it and issue a new one. Every run **generates a fresh secret,
  overwrites the stored one, and restarts the daemon** with it — there is no read-only mode.
  Rotating does not disconnect players already seated in a running game (D14's join secret gates
  the lobby door, not an in-progress session); it only invalidates the old value for anyone who
  has not yet joined or created a game. Completes in a few seconds, safe to repeat.

- **Games in Progress** (`games-in-progress`) — read-only, changes nothing, safe to run at any
  time. Lists every game and lobby on the server with its code, players, Day/Stage/phase, who it
  is waiting on, when it started and when it last moved. Run it to find a game that has stalled —
  a `Last move` days old with a named player under `Waiting on` is someone who is not coming back.
  Returns quickly; the server answers from memory.

- **Manage Game** (`manage-game`) — pick a game from a dropdown built live from the server, then
  either **Export** it (returns the complete save as copyable text and changes nothing) or **End**
  it (deletes it from the server, disconnects anyone still watching, and removes its files and
  index entry). **Ending cannot be undone and is not idempotent** — a second attempt reports that
  the game no longer exists. It always returns the deleted game's save, so nothing is destroyed
  without being handed back first; that text is the only remaining copy, so keep it if the game is
  worth replaying. This is the only way a game ends other than being played to a finish: an
  abandoned game otherwise stays active and is resumed on every restart indefinitely.

## Tasks

- **Get the join secret to share with players** — raised on install, severity `critical`. Points
  at the **Get Join Secret** action. Clears the moment that action is run for the first time; it
  does not return afterward (running it again to rotate does not re-raise it).

## Health Checks

- **Multiplayer Server** — fetches the server's own `/api/health` and reports what it says:
  *"Multiplayer server is ready — 3 games in progress"*, with *", 1 waiting to start"* appended
  only when a lobby exists, and *"no games in progress"* on an idle server. So the check that
  proves the server is answering also says how much is going on.

  A server that does not answer is reported as **starting, never failed**. The server replays its
  saved games before binding its port, so a boot legitimately looks like nothing is listening, and
  calling that a failure would make an ordinary restart look like a crash. Replaying measures
  around 100 ms per game and only unfinished games are replayed, so in practice this window is a
  fraction of a second. A check stuck on "starting" for much longer means the daemon is failing to
  come up — read the service logs, where a refused resume names the game and the version that
  wrote it.

## Backups and Restore

Strategy: the entire `data` volume is backed up wholesale (`ofVolumes`) — every file copied
exactly as it sits on disk, nothing dumped and replayed.

That includes every game's full intent history, so a restore can resume any in-progress game
exactly where it left off, and the join secret in `store.json`, so previously shared join links
keep working after a restore. Nothing needs to be rebuilt or re-entered after a restore; the
server resumes every saved game on boot the same way it does after an ordinary restart.

## Limitations and Differences

1. **No compile step.** The image runs the server directly from TypeScript source using Node's
   native type stripping, rather than building a `dist/` for the server the way the browser
   client is built. This is upstream's own deployment shape (`docs/architecture/deployment.md` in
   the game repo), not something this package changed.
2. **The join secret has no per-player identity.** It is a single server-wide value (D14) that
   gates who may create or join a game — it is not a username or password, and StartOS has no
   visibility into who a player is once they've joined.
3. **No accounts, and one game at a time per person is expected but not enforced** — a deliberate
   upstream design decision (`docs/architecture/multiplayer.md` §11 D13), not a StartOS-specific
   limitation. Since 0.7.0 a browser can hold seats in several games at once and picks between them
   in the lobby, which is a client convenience rather than a change to that decision.
4. **A player's identity lives in their browser.** The session token issued at join is the only
   proof of who a player is; it is kept in that browser's `localStorage` and nowhere else. A player
   may leave a running game and rejoin it (the lobby lists every game the browser is in), but a
   token lost with the browser — cleared site data, a different device — cannot be recovered from
   this package, and the seat stays in the game waiting. Upstream `TODO.md` tracks an
   administrator-issued rejoin link; it does not exist yet.

---

## Quick Reference for AI Consumers

```yaml
package_id: station-master
image: built from source (Dockerfile)
architectures: [x86_64, aarch64]
subcontainers: [station-master-sub]
volumes:
  data: /data
file_models:
  - store.json
startos_managed_env_vars:
  - DATA_DIR
  - JOIN_SECRET
  - ADMIN_SECRET
dependencies: none
interfaces:
  ui: { type: ui, port: 8081 }
actions:
  - get-join-secret
  - games-in-progress
  - manage-game
tasks:
  - { action: get-join-secret, severity: critical }
health_checks:
  - Multiplayer Server
```