A room whose ledger cannot be read is logged and left unloaded, not the server down; the server has tests of its own

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jm2auWk6RP71CjaAb4FMoG

template/deploy/replay-ledgers.ts

@@ -39,7 +39,10 @@ async function main(): Promise<void> {
 		try {
 			for (const line of lines) {
 				if (line.t === 'seat') seats.push(line);
-				else if (line.t === 'unseat') seats.splice(seats.findIndex((s) => s.id === line.id), 1);
+				else if (line.t === 'unseat') {
+					const i = seats.findIndex((s) => s.id === line.id);
+					if (i >= 0) seats.splice(i, 1);
+				}
 				else if (line.t === 'start') state = game.create(Object.fromEntries(seats.map((s) => [s.id, s.name])), line.seed, line.rules, options);
 				else if (line.t === 'turn' && state) {
 					state = game.resolve(state, line.inputs);

template/server/src/rooms.test.ts

@@ -0,0 +1,46 @@
+import { appendFileSync, mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { game, type Input, type State } from '../../src/lib/game';
+import type { GameSpec } from '../../src/lib/game/spec';
+import { Rooms } from './rooms';
+import { Store } from './store';
+
+let dir: string;
+beforeEach(() => {
+	dir = mkdtempSync(join(tmpdir(), 'rooms-'));
+});
+afterEach(() => {
+	rmSync(dir, { recursive: true, force: true });
+});
+
+/** A table of the demo game: the host and a second person, the game begun. */
+function table(spec: GameSpec<State, Input> = game) {
+	const rooms = new Rooms(spec, new Store(dir));
+	const host = rooms.create('Ann', 2);
+	const guest = rooms.join(host.room, 'Bo');
+	rooms.begin(host.room, host.token);
+	return { rooms, room: host.room, ann: host.token, bo: guest.token };
+}
+
+describe('rooms', () => {
+	it('resolves a round once every seat has moved, and refuses a move for a round already played', () => {
+		const { rooms, room, ann, bo } = table();
+		rooms.submit(room, ann, { pick: 5 }, 0);
+		expect(rooms.waitingOn(room)).toEqual(['B']);
+		rooms.submit(room, bo, { pick: 2 }, 0);
+		expect(room.resolved).toBe(1);
+		expect(() => rooms.submit(room, ann, { pick: 4 }, 0)).toThrow(/already been played/);
+	});
+
+	it('leaves a room with an unreadable ledger unloaded and opens the rest', () => {
+		const { room } = table();
+		appendFileSync(join(dir, 'ZZZZ.jsonl'), '{"t":"room","id":"ZZZZ","seats":2,"createdAt":1,"options":{}}\n{"t":"seat", torn');
+		const errors = vi.spyOn(console, 'error').mockImplementation(() => {});
+		const reopened = new Rooms(game, new Store(dir));
+		expect(errors).toHaveBeenCalledWith(expect.stringMatching(/ZZZZ: ledger unreadable/));
+		expect(reopened.get(room.id).state).not.toBeNull();
+		errors.mockRestore();
+	});
+});

template/server/src/rooms.ts

@@ -120,7 +120,14 @@ export class Rooms<State, Input> {
 		private keeper: { name: string; zone: string } = { name: 'the keeper', zone: 'UTC' }
 	) {
 		for (const id of store.roomIds()) {
-			const room = this.replay(id, store.read(id));
+			let room: Room<State> | null;
+			try {
+				room = this.replay(id, store.read(id));
+			} catch (e) {
+				// One unreadable ledger (a torn last line) keeps its room closed, not the server down.
+				console.error(`room ${id}: ledger unreadable, left unloaded: ${e instanceof Error ? e.message : String(e)}`);
+				continue;
+			}
 			if (!room) continue;
 			this.rooms.set(id, room);
 			// A table that stopped with a bot's move owed picks up where it left off.

template/server/src/tally.ts

@@ -30,7 +30,12 @@ export class Tallies<State, Input> {
 		const names = new Set<string>();
 		let firstStart = Infinity;
 		for (const id of this.store.roomIds()) {
-			const lines = this.store.read(id);
+			let lines: LedgerLine[];
+			try {
+				lines = this.store.read(id);
+			} catch {
+				continue; // an unreadable ledger is left out of the count, as its room is left unloaded
+			}
 			if (lines[0]?.t !== 'room') continue;
 			t.tablesOpened += 1;
 			const seats: { id: SeatId; name: string; bot: boolean }[] = [];
@@ -44,8 +49,10 @@ export class Tallies<State, Input> {
 					seats.push(line);
 					if (line.bot) hasBot = true;
 					else names.add(line.name.toLowerCase());
-				} else if (line.t === 'unseat') seats.splice(seats.findIndex((s) => s.id === line.id), 1);
+				} else if (line.t === 'unseat') {
-				else if (line.t === 'start') {
+					const i = seats.findIndex((s) => s.id === line.id);
+					if (i >= 0) seats.splice(i, 1);
+				} else if (line.t === 'start') {
 					t.gamesBegun += 1;
 					if (hasBot) t.gamesWithBot += 1;
 					if (lines[0].createdAt < firstStart) firstStart = lines[0].createdAt;

template/vite.config.ts

@@ -21,6 +21,6 @@ export default defineConfig({
 		}
 	},
 	test: {
-		include: ['src/**/*.test.ts']
+		include: ['src/**/*.test.ts', 'server/src/**/*.test.ts']
 	}
 });