Queue native collection launches before async placement

src/lib/server/provisioning/launch-preparation.ts

@@ -4,6 +4,7 @@ import { config } from '../config.js';
 import { db } from '../db/index.js';
 import type { NativeInstance } from '../backends/native.js';
 import type { LaunchRecipePlan } from '../fleet/launch-recipes.js';
+import type { PlacementOptions } from '../hosts/capacity.js';
 
 export interface NativeLaunchInput {
     game: 't5' | 't6';
@@ -25,7 +26,7 @@ export interface PreparedNativeLaunch {
 let worker: Worker | null = null;
 let sequence = 0;
 const pending = new Map<number, {
-    resolve: (value: PreparedNativeLaunch) => void;
+    resolve: (value: unknown) => void;
     reject: (error: Error) => void;
     timer: NodeJS.Timeout;
 }>();
@@ -39,14 +40,14 @@ function stop(error: Error, current = worker): Promise<number> | undefined {
 }
 
 /** The reader and JSON encoder run off the controller's request thread. */
-export function prepareNativeLaunch(input: NativeLaunchInput): Promise<PreparedNativeLaunch> {
+function run<T>(kind: 'launch' | 'placement', input: NativeLaunchInput | PlacementOptions): Promise<T> {
     db(); // Migrations must finish before the independent read-only connection opens.
     if (!worker) {
         const current = worker = new Worker(resolve(process.env.NODE_ENV === 'production'
             ? 'build/launch/worker.mjs' : '.svelte-kit/launch/worker.mjs'), {
             workerData: { dbPath: resolve(config.dbPath) }
         });
-        current.on('message', ({ id, value, error }: { id: number; value: PreparedNativeLaunch; error?: string }) => {
+        current.on('message', ({ id, value, error }: { id: number; value: unknown; error?: string }) => {
             if (current !== worker) return;
             const request = pending.get(id);
             if (!request) return;
@@ -59,13 +60,18 @@ export function prepareNativeLaunch(input: NativeLaunchInput): Promise<PreparedN
     }
     worker.ref();
     const id = ++sequence;
-    return new Promise((resolve, reject) => {
+    return new Promise<T>((resolve, reject) => {
         const timer = setTimeout(() => { void stop(new Error('Launch preparation timed out; preparation will retry.')); }, 60_000);
-        pending.set(id, { resolve, reject, timer });
-        worker!.postMessage({ id, input });
+        pending.set(id, { resolve: value => resolve(value as T), reject, timer });
+        worker!.postMessage({ id, kind, input });
     });
 }
 
+export function prepareNativeLaunch(input: NativeLaunchInput): Promise<PreparedNativeLaunch> { return run('launch', input); }
+export function evaluateNativePlacement(input: PlacementOptions): Promise<{ hostId: string; lastHeartbeat: string | null }> {
+    return run('placement', input);
+}
+
 export async function closeLaunchPreparation(): Promise<void> {
     await stop(new Error('Launch preparation stopped.'));
 }