Support RSC Framework Mode in react-router-serve

integration/helpers/rsc-vite-framework/package.json

@@ -30,6 +30,7 @@
   },
   "dependencies": {
     "@mjackson/node-fetch-server": "0.6.1",
+    "@react-router/serve": "workspace:*",
     "compression": "^1.8.0",
     "express": "^4.21.2",
     "react": "^19.0.0",

integration/helpers/vite.ts

@@ -373,31 +373,6 @@ export const reactRouterServe = async ({
   return () => serveProc.kill();
 };
 
-export const runStartScript = async ({
-  cwd,
-  port,
-  viteBase,
-  basename,
-}: {
-  cwd: string;
-  port: number;
-  viteBase?: string;
-  basename?: string;
-}) => {
-  let nodeBin = process.argv[0];
-  let proc = spawn(nodeBin, ["start.js"], {
-    cwd,
-    stdio: "pipe",
-    env: {
-      NODE_ENV: "production",
-      PORT: port.toFixed(0),
-      VITE_BASE: viteBase,
-    },
-  });
-  await waitForServer(proc, { port, basename });
-  return () => proc.kill();
-};
-
 export const wranglerPagesDev = async ({
   cwd,
   port,

integration/react-router-serve-test.ts

@@ -0,0 +1,84 @@
+import { test, expect } from "@playwright/test";
+
+import { PlaywrightFixture } from "./helpers/playwright-fixture.js";
+import type { Fixture, AppFixture } from "./helpers/create-fixture.js";
+import {
+  createAppFixture,
+  createFixture,
+  js,
+} from "./helpers/create-fixture.js";
+import { type TemplateName } from "./helpers/vite.js";
+
+const templateNames = [
+  "vite-5-template",
+  "rsc-vite-framework",
+] as const satisfies TemplateName[];
+
+test.describe("react-router-serve", () => {
+  for (const templateName of templateNames) {
+    test.describe(`template: ${templateName}`, () => {
+      let fixture: Fixture;
+      let appFixture: AppFixture;
+
+      test.beforeEach(async ({ context }) => {
+        await context.route(/\.(data|rsc)$/, async (route) => {
+          await new Promise((resolve) => setTimeout(resolve, 50));
+          route.continue();
+        });
+      });
+
+      test.beforeAll(async () => {
+        fixture = await createFixture({
+          templateName,
+          useReactRouterServe: true,
+          files: {
+            "app/routes/_index.tsx": js`
+              import { useLoaderData, Link } from "react-router";
+
+              export function loader() {
+                return "pizza";
+              }
+
+              export default function Index() {
+                let data = useLoaderData();
+                return (
+                  <div>
+                    {data}
+                    <Link to="/burgers">Other Route</Link>
+                  </div>
+                )
+              }
+            `,
+
+            "app/routes/burgers.tsx": js`
+              export default function Index() {
+                return <div>cheeseburger</div>;
+              }
+            `,
+          },
+        });
+
+        // This creates an interactive app using playwright.
+        appFixture = await createAppFixture(fixture);
+      });
+
+      test.afterAll(() => {
+        appFixture.close();
+      });
+
+      test("should start and perform client side navigation", async ({
+        page,
+      }) => {
+        let app = new PlaywrightFixture(appFixture, page);
+        // You can test any request your app might get using `fixture`.
+        let response = await fixture.requestDocument("/");
+        expect(await response.text()).toMatch("pizza");
+
+        // If you need to test interactivity use the `app`
+        await app.goto("/");
+        await app.clickLink("/burgers");
+        await page.waitForSelector("text=cheeseburger");
+      });
+    });
+  }
+});

integration/vite-basename-test.ts

@@ -10,7 +10,6 @@ import {
   viteConfig,
   dev,
   viteDevCmd,
-  runStartScript,
   reactRouterServe,
   reactRouterConfig,
   type TemplateName,
@@ -399,9 +398,7 @@ test.describe("Vite base + React Router basename", () => {
           );
           build({ cwd });
           if (startServer !== false) {
-            stop = templateName.includes("rsc")
-              ? await runStartScript({ cwd, port, viteBase: base, basename })
-              : await reactRouterServe({ cwd, port, basename });
+            stop = await reactRouterServe({ cwd, port, basename });
           }
         }
 

integration/vite-css-test.ts

@@ -7,7 +7,6 @@ import {
   createEditor,
   dev,
   build,
-  runStartScript,
   reactRouterServe,
   customDev,
   EXPRESS_SERVER,
@@ -380,9 +379,7 @@ test.describe("Vite CSS", () => {
           }
           expect(stderrString).toBeFalsy();
           expect(status).toBe(0);
-          stop = templateName.includes("rsc")
-            ? await runStartScript({ cwd, port })
-            : await reactRouterServe({ cwd, port });
+          stop = await reactRouterServe({ cwd, port });
         });
         test.afterAll(() => stop());
 
@@ -446,9 +443,7 @@ test.describe("Vite CSS", () => {
           });
           expect(stderr.toString()).toBeFalsy();
           expect(status).toBe(0);
-          stop = templateName.includes("rsc")
-            ? await runStartScript({ cwd, port })
-            : await reactRouterServe({ cwd, port });
+          stop = await reactRouterServe({ cwd, port });
         });
         test.afterAll(() => stop());
 

packages/react-router-dev/config/default-rsc-entries/entry.rsc.tsx

@@ -10,6 +10,7 @@ import { unstable_matchRSCServerRequest as matchRSCServerRequest } from "react-r
 
 import routes from "virtual:react-router/unstable_rsc/routes";
 import basename from "virtual:react-router/unstable_rsc/basename";
+import unstable_reactRouterServeConfig from "virtual:react-router/unstable_rsc/react-router-serve-config";
 
 export async function fetchServer(request: Request) {
   return await matchRSCServerRequest({
@@ -30,6 +31,8 @@ export async function fetchServer(request: Request) {
   });
 }
 
+export { unstable_reactRouterServeConfig };
+
 export default async function handler(request: Request) {
   const ssr = await import.meta.viteRsc.loadModule<
     typeof import("./entry.ssr")

packages/react-router-dev/vite/rsc/plugin.ts

@@ -9,6 +9,7 @@ import * as Typegen from "../../typegen";
 import { readFileSync } from "fs";
 import { readFile } from "fs/promises";
 import path, { join, dirname } from "pathe";
+import invariant from "../../invariant";
 import {
   type ConfigLoader,
   type ResolvedReactRouterConfig,
@@ -31,6 +32,7 @@ export function reactRouterRSCVitePlugin(): Vite.PluginOption[] {
   let configLoader: ConfigLoader;
   let typegenWatcherPromise: Promise<Typegen.Watcher> | undefined;
   let viteCommand: Vite.ConfigEnv["command"];
+  let resolvedViteConfig: Vite.ResolvedConfig;
   let routeIdByFile: Map<string, string> | undefined;
   let logger: Vite.Logger;
 
@@ -224,6 +226,9 @@ export function reactRouterRSCVitePlugin(): Vite.PluginOption[] {
           },
         };
       },
+      configResolved(viteConfig) {
+        resolvedViteConfig = viteConfig;
+      },
       async configureServer(viteDevServer) {
         configLoader.onChange(
           async ({
@@ -492,6 +497,30 @@ export function reactRouterRSCVitePlugin(): Vite.PluginOption[] {
         return modules;
       },
     },
+    {
+      name: "react-router/rsc/virtual-react-router-serve-config",
+      resolveId(id) {
+        if (id === virtual.reactRouterServeConfig.id) {
+          return virtual.reactRouterServeConfig.resolvedId;
+        }
+      },
+      load(id) {
+        if (id === virtual.reactRouterServeConfig.resolvedId) {
+          const rscOutDir = resolvedViteConfig.environments.rsc?.build?.outDir;
+          invariant(rscOutDir, "RSC build directory config not found");
+          const clientOutDir =
+            resolvedViteConfig.environments.client?.build?.outDir;
+          invariant(clientOutDir, "Client build directory config not found");
+          const assetsBuildDirectory = Path.relative(rscOutDir, clientOutDir);
+          const publicPath = resolvedViteConfig.base;
+
+          return `export default ${JSON.stringify({
+            assetsBuildDirectory,
+            publicPath,
+          })};`;
+        }
+      },
+    },
     validatePluginOrder(),
     warnOnClientSourceMaps(),
   ];
@@ -503,6 +532,7 @@ const virtual = {
   hmrRuntime: create("unstable_rsc/runtime"),
   basename: create("unstable_rsc/basename"),
   rscEntry: create("unstable_rsc/rsc-entry"),
+  reactRouterServeConfig: create("unstable_rsc/react-router-serve-config"),
 };
 
 function invalidateVirtualModules(viteDevServer: Vite.ViteDevServer) {