feat(desktop,host-service): forward remote workspace ports to the local machine

apps/desktop/src/lib/trpc/routers/index.ts

@@ -21,6 +21,7 @@ import { createNotificationsRouter } from "./notifications";
 import { createPageContentRouter } from "./page-content";
 import { createPermissionsRouter } from "./permissions";
 import { createPluginsRouter } from "./plugins";
+import { createPortForwardsRouter } from "./port-forwards";
 import { createPortsRouter } from "./ports";
 import { createProjectsRouter } from "./projects";
 import { createResourceMetricsRouter } from "./resource-metrics";
@@ -54,6 +55,7 @@ export const createAppRouter = (getWindow: () => BrowserWindow | null) => {
 		permissions: createPermissionsRouter(),
 		plugins: createPluginsRouter(),
 		ports: createPortsRouter(),
+		portForwards: createPortForwardsRouter(),
 		resourceMetrics: createResourceMetricsRouter(),
 		menu: createMenuRouter(),
 		external: createExternalRouter(),

apps/desktop/src/lib/trpc/routers/port-forwards/index.ts

@@ -0,0 +1 @@
+export { createPortForwardsRouter } from "./port-forwards";

apps/desktop/src/lib/trpc/routers/port-forwards/port-forwards.ts

@@ -0,0 +1,54 @@
+import { observable } from "@trpc/server/observable";
+import { portForwardManager, setRelayToken } from "main/lib/port-forward";
+import type { PortForward } from "shared/types";
+import { z } from "zod";
+import { publicProcedure, router } from "../..";
+
+export const createPortForwardsRouter = () => {
+	return router({
+		setRelayToken: publicProcedure
+			.input(z.object({ token: z.string().nullable() }))
+			.mutation(({ input }) => {
+				setRelayToken(input.token);
+			}),
+
+		list: publicProcedure.query((): PortForward[] => portForwardManager.list()),
+
+		subscribe: publicProcedure
+			.input(z.object({ clientId: z.string() }))
+			.subscription(({ input }) => {
+				return observable<PortForward[]>((emit) => {
+					const onChange = (forwards: PortForward[]) => emit.next(forwards);
+					portForwardManager.on("change", onChange);
+					emit.next(portForwardManager.list());
+					return () => {
+						portForwardManager.off("change", onChange);
+						// The subscription is per window; its teardown is how the
+						// manager learns a window (and its wanted set) is gone.
+						void portForwardManager.releaseClient(input.clientId);
+					};
+				});
+			}),
+
+		sync: publicProcedure
+			.input(
+				z.object({
+					clientId: z.string(),
+					hostUrl: z.string(),
+					workspaceId: z.string(),
+					ports: z.array(z.number().int().positive()),
+				}),
+			)
+			.mutation(
+				({ input }): Promise<PortForward[]> => portForwardManager.sync(input),
+			),
+
+		retryEphemeral: publicProcedure
+			.input(z.object({ id: z.string() }))
+			.mutation(({ input }) => portForwardManager.retryEphemeral(input.id)),
+
+		killLocalOwner: publicProcedure
+			.input(z.object({ id: z.string() }))
+			.mutation(({ input }) => portForwardManager.killLocalOwner(input.id)),
+	});
+};

apps/desktop/src/main/index.ts

@@ -42,6 +42,7 @@ import {
 	shutdownTanstackDbPersistence,
 } from "./lib/persistence/persistence";
 import { syncInstalledPluginMcpServers } from "./lib/plugin-installs";
+import { portForwardManager } from "./lib/port-forward";
 import { ensureProjectIconsDir, getProjectIconPath } from "./lib/project-icons";
 import { runQuitCleanup } from "./lib/quit-sequence";
 import { initSentry } from "./lib/sentry";
@@ -255,6 +256,9 @@ app.on("before-quit", async (event) => {
 	}
 
 	isQuitting = true;
+	// Local port-forward listeners hold no state worth draining; drop them so
+	// nothing keeps 127.0.0.1:<port> bound after the app is gone.
+	portForwardManager.stopAll();
 	// Snapshot all open windows (bounds + org) before they close, so relaunch
 	// restores them. markAppQuitting() stops per-window close handlers from
 	// shrinking the set as windows close one-by-one.

apps/desktop/src/main/lib/host-service-utils.ts

@@ -47,7 +47,7 @@ function normalizePort(port: number): number | null {
 	return port;
 }
 
-function canBindPort(port: number): Promise<boolean> {
+export function canBindPort(port: number): Promise<boolean> {
 	return new Promise((resolve) => {
 		const server = createServer();
 		const finish = (available: boolean) => {

apps/desktop/src/main/lib/port-forward/index.ts

@@ -0,0 +1,22 @@
+import { canBindPort } from "../host-service-utils";
+import { portManager } from "../terminal/port-manager";
+import { PortForwardManager } from "./port-forward-manager";
+import { RelayForwardTransport } from "./relay-forward-transport";
+
+export { PortForwardManager } from "./port-forward-manager";
+export { RelayForwardTransport } from "./relay-forward-transport";
+export type { ForwardTransport } from "./types";
+
+let relayToken: string | null = null;
+
+export function setRelayToken(token: string | null): void {
+	relayToken = token;
+}
+
+export const portForwardManager = new PortForwardManager({
+	transport: new RelayForwardTransport({ getToken: () => relayToken }),
+	getLocalPorts: () => portManager.getAllPorts(),
+	killLocalPort: ({ terminalId, workspaceId, port }) =>
+		portManager.killPort({ terminalId, workspaceId, port }),
+	canBindPort,
+});