feat: add default fetch handler export for server build

Author: edmundhung

.changeset/add-fetch-handler-export.md

@@ -0,0 +1,5 @@
+---
+"@react-router/dev": minor
+---
+
+Add `@react-router/dev/config/default-fetch-handler` package export that provides a default fetch handler for the server build.

integration/helpers/vite-plugin-cloudflare-template/package.json

@@ -19,7 +19,7 @@
     "serialize-javascript": "^6.0.1"
   },
   "devDependencies": {
-    "@cloudflare/vite-plugin": "^1.9.0",
+    "@cloudflare/vite-plugin": "^1.24.0",
     "@react-router/dev": "workspace:*",
     "@react-router/fs-routes": "workspace:*",
     "@types/node": "^20.0.0",
@@ -29,7 +29,7 @@
     "typescript": "catalog:",
     "vite": "^6.3.0",
     "vite-tsconfig-paths": "^4.2.1",
-    "wrangler": "^4.23.0"
+    "wrangler": "^4.64.0"
   },
   "engines": {
     "node": ">=20.0.0"

integration/helpers/vite-plugin-cloudflare-template/tsconfig.cloudflare.json

@@ -5,7 +5,6 @@
     "app/**/*",
     "app/**/.server/**/*",
     "app/**/.client/**/*",
-    "workers/**/*",
     "worker-configuration.d.ts"
   ],
   "compilerOptions": {

integration/helpers/vite-plugin-cloudflare-template/workers/app.ts

@@ -1,6 +1,6 @@
 name = "react-router-app"
 compatibility_date = "2025-03-17"
-main = "./workers/app.ts"
+main = "@react-router/dev/config/default-fetch-handler"
 
 assets = {}
 

integration/helpers/vite-plugin-cloudflare-template/wrangler.toml

@@ -24,9 +24,10 @@ function defineFiles({
     });
   `,
     "app/routes/env.tsx": tsx`
+    import { env } from "cloudflare:workers";
     import type { Route } from "./+types/env";
-    export function loader({ context }: Route.LoaderArgs) {
-      return { message: context.cloudflare.env.VALUE_FROM_CLOUDFLARE };
+    export function loader() {
+      return { message: env.VALUE_FROM_CLOUDFLARE };
     }
     export default function EnvRoute({ loaderData }: Route.RouteComponentProps) {
       return <div data-loader-message>{loaderData.message}</div>;

integration/vite-plugin-cloudflare-test.ts

@@ -0,0 +1,13 @@
+import { createRequestHandler } from "react-router";
+
+const handler = createRequestHandler(
+  // @ts-expect-error - no types for this
+  () => import("virtual:react-router/server-build"),
+  import.meta.env.MODE,
+);
+
+export default {
+  async fetch(request: Request) {
+    return handler(request);
+  },
+};

packages/react-router-dev/config/default-fetch-handler.ts

@@ -16,6 +16,7 @@
     "./config/default-rsc-entries/entry.client": "./dist/config/default-rsc-entries/entry.client.tsx",
     "./config/default-rsc-entries/entry.rsc": "./dist/config/default-rsc-entries/entry.rsc.tsx",
     "./config/default-rsc-entries/entry.ssr": "./dist/config/default-rsc-entries/entry.ssr.tsx",
+    "./config/default-fetch-handler": "./dist/config/default-fetch-handler.ts",
     "./config": {
       "types": "./dist/config.d.ts",
       "default": "./dist/config.js"

packages/react-router-dev/package.json

@@ -72,6 +72,11 @@ export default defineConfig([
               `dist/config/default-rsc-entries/${file}`,
             );
           }
+
+          await fsp.copyFile(
+            "config/default-fetch-handler.ts",
+            "dist/config/default-fetch-handler.ts",
+          );
         },
       },
     ],