[rooms] support for mitm

packages/domain/src/index.ts

@@ -8,6 +8,7 @@ export {
 } from './enums'
 export * from './accounts-db'
 export * from './studio-unity-assets'
+export * from './unity-assets-db'
 export * from './audit-db'
 export * from './clubs-db'
 export * from './d1-binds'

packages/domain/src/unity-assets-db.ts

@@ -0,0 +1,119 @@
+/**
+ * Baked unity asset bundles — the blob references behind a room's asset-bundle download.
+ *
+ * `unity_asset` holds one row per BUILD of a unity asset: the asset's GUID, the `Target`
+ * it was built for (0 Windows, 2 Android/Quest — the same numbers a custom avatar's
+ * `unityAssetTarget` uses), its `Version`, and the storage blob the client downloads
+ * (`Filename`, a `<date>/<guid>` path, and its base64 SHA-256 `Hash`). The client asks for
+ * these in bulk from `POST /unity_assets/baked/bulk` (the `rooms` worker) while loading a
+ * room — the step Player.log times as `AssetBundle_Download` — and downloads `Filename`
+ * from the CDN; a lookup that answers no row, or a row without a `Filename`, simply
+ * downloads nothing, with no error anywhere.
+ *
+ * This is a separate store from the Rec Room Studio builds in `studio_unity_asset_file`
+ * (see studio-unity-assets.ts), which the studio worker writes per platform and kind and
+ * which `GET /rooms/{id}` folds onto `CurrentSave.UnitySubAssets`. Nothing writes this
+ * table yet; it is the record the bulk lookup reads.
+ *
+ * The `rooms` worker owns the table and its migration — see
+ * apps/rooms/migrations/0024_unity_asset.sql.
+ */
+
+import { bindPlaceholders, chunkForBinds } from './d1-binds'
+
+/** Schema DDL (mirror of apps/rooms/migrations/0024_unity_asset.sql) — tests apply this. */
+export const UNITY_ASSET_SCHEMA_DDL: string[] = [
+	// A unity asset is built once per target, and may be rebuilt at a new version, so the
+	// three together name a row. `unity_asset_id` is stored lowercase: a GUID's case is not
+	// part of its identity and the client is not consistent about it.
+	`CREATE TABLE IF NOT EXISTS unity_asset (
+		unity_asset_id TEXT NOT NULL,
+		target INTEGER NOT NULL,
+		version INTEGER NOT NULL,
+		filename TEXT NOT NULL,
+		hash TEXT NOT NULL,
+		PRIMARY KEY (unity_asset_id, target, version)
+	)`,
+]
+
+/**
+ * One baked bundle as the client reads it — its five-key DTO, in this order. An element of
+ * the bare array `POST /unity_assets/baked/bulk` answers.
+ */
+export interface BakedUnityAsset {
+	/** GUID. */
+	UnityAssetId: string
+	/** 0 Windows, 2 Android/Quest. */
+	Target: number
+	Version: number
+	/** The storage blob path the client downloads, `<date>/<guid>`. */
+	Filename: string
+	/** Base64 SHA-256 of the blob. */
+	Hash: string
+}
+
+interface UnityAssetRow {
+	unity_asset_id: string
+	target: number
+	version: number
+	filename: string
+	hash: string
+}
+
+const toBakedUnityAsset = (row: UnityAssetRow): BakedUnityAsset => ({
+	UnityAssetId: row.unity_asset_id,
+	Target: row.target,
+	Version: row.version,
+	Filename: row.filename,
+	Hash: row.hash,
+})
+
+/** Record a build. Replaces the row for the same (asset, target, version). */
+export async function putUnityAsset(db: D1Database, asset: BakedUnityAsset): Promise<void> {
+	await db
+		.prepare(
+			`INSERT OR REPLACE INTO unity_asset (unity_asset_id, target, version, filename, hash)
+			 VALUES (?1, ?2, ?3, ?4, ?5)`
+		)
+		.bind(asset.UnityAssetId.toLowerCase(), asset.Target, asset.Version, asset.Filename, asset.Hash)
+		.run()
+}
+
+/**
+ * The baked bundles for `unityAssetIds` on `target` — one entry per asset that has one, in
+ * the order asked, assets with no build left out. An asset built more than once is served
+ * ONCE: the build at the requested `version` when there is one, otherwise the newest. The
+ * request's version is a preference, not a filter, because the one capture pairing the two
+ * (a request for version 3 answered with version 227) shows the reference did not require
+ * them to match, and an empty answer here is a room that silently loads nothing.
+ *
+ * Ids are matched case-insensitively and served as stored (lowercase). Nothing to ask
+ * about reads nothing.
+ */
+export async function getBakedUnityAssets(
+	db: D1Database,
+	unityAssetIds: string[],
+	target: number,
+	version: number
+): Promise<BakedUnityAsset[]> {
+	const ids = [...new Set(unityAssetIds.map((id) => id.toLowerCase()))]
+	if (ids.length === 0) return []
+	const pages = await Promise.all(
+		chunkForBinds(ids, 2).map((chunk) =>
+			db
+				.prepare(
+					`SELECT unity_asset_id, target, version, filename, hash FROM unity_asset
+					 WHERE target = ?1 AND unity_asset_id IN (${bindPlaceholders(chunk, 2)})
+					 ORDER BY (version = ?2) DESC, version DESC`
+				)
+				.bind(target, version, ...chunk)
+				.all<UnityAssetRow>()
+		)
+	)
+	// Rows arrive best-first per asset, so the first one seen for an id is the one to serve.
+	const best = new Map<string, BakedUnityAsset>()
+	for (const row of pages.flatMap((page) => page.results)) {
+		if (!best.has(row.unity_asset_id)) best.set(row.unity_asset_id, toBakedUnityAsset(row))
+	}
+	return ids.flatMap((id) => best.get(id) ?? [])
+}