feat: unstable_subResourceIntegrity

.changeset/late-falcons-sort.md

@@ -0,0 +1,6 @@
+---
+"@react-router/dev": patch
+"react-router": patch
+---
+
+Introduce `unstable_subResourceIntegrity` future flag that enables generation of an importmap with integrity for the scripts that will be loaded by the browser.

.github/workflows/shared-build.yml

@@ -22,7 +22,8 @@ jobs:
           node-version-file: ".nvmrc"
           cache: "pnpm"
 
-      - uses: google/wireit@setup-github-actions-caching/v2
+      # TODO: Track and renable once this has been fixed: https://github.com/google/wireit/issues/1297
+      # - uses: google/wireit@setup-github-actions-caching/v2
 
       - name: Disable GitHub Actions Annotations
         run: |

.github/workflows/shared-integration.yml

@@ -45,7 +45,8 @@ jobs:
           node-version: ${{ matrix.node }}
           cache: "pnpm"
 
-      - uses: google/wireit@setup-github-actions-caching/v2
+      # TODO: Track and renable once this has been fixed: https://github.com/google/wireit/issues/1297
+      # - uses: google/wireit@setup-github-actions-caching/v2
 
       - name: Disable GitHub Actions Annotations
         run: |

.github/workflows/test.yml

@@ -45,7 +45,8 @@ jobs:
           cache: pnpm
           check-latest: true
 
-      - uses: google/wireit@setup-github-actions-caching/v2
+      # TODO: Track and renable once this has been fixed: https://github.com/google/wireit/issues/1297
+      # - uses: google/wireit@setup-github-actions-caching/v2
 
       - name: Disable GitHub Actions Annotations
         run: |

packages/react-router-dev/config/config.ts

@@ -92,6 +92,7 @@ interface FutureConfig {
    * Automatically split route modules into multiple chunks when possible.
    */
   unstable_splitRouteModules: boolean | "enforce";
+  unstable_subResourceIntegrity: boolean;
   /**
    * Use Vite Environment API (experimental)
    */
@@ -497,6 +498,8 @@ async function resolveConfig({
       reactRouterUserConfig.future?.unstable_optimizeDeps ?? false,
     unstable_splitRouteModules:
       reactRouterUserConfig.future?.unstable_splitRouteModules ?? false,
+    unstable_subResourceIntegrity:
+      reactRouterUserConfig.future?.unstable_subResourceIntegrity ?? false,
     unstable_viteEnvironmentApi:
       reactRouterUserConfig.future?.unstable_viteEnvironmentApi ?? false,
   };

packages/react-router-dev/manifest.ts

@@ -28,6 +28,7 @@ export type Manifest = {
   routes: {
     [routeId: string]: ManifestRoute;
   };
+  sri: Record<string, string> | undefined;
   hmr?: {
     timestamp?: number;
     runtime: string;

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

@@ -2,6 +2,7 @@
 // context but want to use Vite's ESM build to avoid deprecation warnings
 import type * as Vite from "vite";
 import { type BinaryLike, createHash } from "node:crypto";
+import * as fs from "node:fs";
 import * as path from "node:path";
 import * as url from "node:url";
 import * as fse from "fs-extra";
@@ -805,6 +806,39 @@ export const reactRouterVitePlugin: ReactRouterVitePlugin = () => {
     return new Set([...cssUrlPaths, ...chunkAssetPaths]);
   };
 
+  let generateSriManifest = async (ctx: ReactRouterPluginContext) => {
+    let clientBuildDirectory = getClientBuildDirectory(ctx.reactRouterConfig);
+    // walk the client build directory and generate SRI hashes for all .js files
+    let entries = fs.readdirSync(clientBuildDirectory, {
+      withFileTypes: true,
+      recursive: true,
+    });
+    let sriManifest: ReactRouterManifest["sri"] = {};
+    for (const entry of entries) {
+      if (entry.isFile() && entry.name.endsWith(".js")) {
+        let contents;
+        try {
+          contents = await fse.readFile(
+            path.join(entry.path, entry.name),
+            "utf-8"
+          );
+        } catch (e) {
+          logger.error(`Failed to read file for SRI generation: ${entry.name}`);
+          throw e;
+        }
+        let hash = createHash("sha384")
+          .update(contents)
+          .digest()
+          .toString("base64");
+        let filepath = getVite().normalizePath(
+          path.relative(clientBuildDirectory, path.join(entry.path, entry.name))
+        );
+        sriManifest[`${ctx.publicPath}${filepath}`] = `sha384-${hash}`;
+      }
+    }
+    return sriManifest;
+  };
+
   let generateReactRouterManifestsForBuild = async ({
     routeIds,
   }: {
@@ -942,6 +976,7 @@ export const reactRouterVitePlugin: ReactRouterVitePlugin = () => {
     let reactRouterBrowserManifest: ReactRouterManifest = {
       ...fingerprintedValues,
       ...nonFingerprintedValues,
+      sri: undefined,
     };
 
     // Write the browser manifest to disk as part of the build process
@@ -952,12 +987,18 @@ export const reactRouterVitePlugin: ReactRouterVitePlugin = () => {
       )};`
     );
 
+    let sri: ReactRouterManifest["sri"] = undefined;
+    if (ctx.reactRouterConfig.future.unstable_subResourceIntegrity) {
+      sri = await generateSriManifest(ctx);
+    }
+
     // The server manifest is the same as the browser manifest, except for
     // server bundle builds which only includes routes for the current bundle,
     // otherwise the server and client have the same routes
     let reactRouterServerManifest: ReactRouterManifest = {
       ...reactRouterBrowserManifest,
       routes: serverRoutes,
+      sri,
     };
 
     return {
@@ -1043,6 +1084,8 @@ export const reactRouterVitePlugin: ReactRouterVitePlugin = () => {
       };
     }
 
+    let sri: ReactRouterManifest["sri"] = undefined;
+
     let reactRouterManifestForDev = {
       version: String(Math.random()),
       url: combineURLs(ctx.publicPath, virtual.browserManifest.url),
@@ -1056,6 +1099,7 @@ export const reactRouterVitePlugin: ReactRouterVitePlugin = () => {
         ),
         imports: [],
       },
+      sri,
       routes,
     };
 

packages/react-router/lib/dom-export/hydrated-router.tsx

@@ -50,6 +50,19 @@ function initSsrInfo(): void {
     window.__reactRouterManifest &&
     window.__reactRouterRouteModules
   ) {
+    if (window.__reactRouterManifest.sri === true) {
+      const importMap = document.querySelector("script[rr-importmap]");
+      if (importMap?.textContent) {
+        try {
+          window.__reactRouterManifest.sri = JSON.parse(
+            importMap.textContent
+          ).integrity;
+        } catch (err) {
+          console.error("Failed to parse import map", err);
+        }
+      }
+    }
+
     ssrInfo = {
       context: window.__reactRouterContext,
       manifest: window.__reactRouterManifest,

packages/react-router/lib/dom/ssr/components.tsx

@@ -785,32 +785,54 @@ import(${JSON.stringify(manifest.entry.module)});`;
 
   let preloads = isHydrated
     ? []
-    : manifest.entry.imports.concat(
-        getModuleLinkHrefs(matches, manifest, {
-          includeHydrateFallback: true,
-        })
+    : dedupe(
+        manifest.entry.imports.concat(
+          getModuleLinkHrefs(matches, manifest, {
+            includeHydrateFallback: true,
+          })
+        )
       );
 
+  let sri = typeof manifest.sri === "object" ? manifest.sri : {};
+
   return isHydrated ? null : (
     <>
+      {typeof manifest.sri === "object" ? (
+        <script
+          rr-importmap=""
+          type="importmap"
+          suppressHydrationWarning
+          dangerouslySetInnerHTML={{
+            __html: JSON.stringify({
+              integrity: sri,
+            }),
+          }}
+        />
+      ) : null}
       {!enableFogOfWar ? (
         <link
           rel="modulepreload"
           href={manifest.url}
           crossOrigin={props.crossOrigin}
+          integrity={sri[manifest.url]}
+          suppressHydrationWarning
         />
       ) : null}
       <link
         rel="modulepreload"
         href={manifest.entry.module}
         crossOrigin={props.crossOrigin}
+        integrity={sri[manifest.entry.module]}
+        suppressHydrationWarning
       />
-      {dedupe(preloads).map((path) => (
+      {preloads.map((path) => (
         <link
           key={path}
           rel="modulepreload"
           href={path}
           crossOrigin={props.crossOrigin}
+          integrity={sri[path]}
+          suppressHydrationWarning
         />
       ))}
       {initialScripts}

packages/react-router/lib/dom/ssr/entry.ts

@@ -42,6 +42,7 @@ export interface EntryContext extends FrameworkContextObject {
 }
 
 export interface FutureConfig {
+  unstable_subResourceIntegrity: boolean;
   unstable_middleware: boolean;
 }
 
@@ -59,4 +60,5 @@ export interface AssetsManifest {
     timestamp?: number;
     runtime: string;
   };
+  sri?: Record<string, string> | true;
 }

packages/react-router/lib/dom/ssr/fog-of-war.ts

@@ -31,7 +31,7 @@ export function isFogOfWarEnabled(ssr: boolean) {
 }
 
 export function getPartialManifest(
-  manifest: AssetsManifest,
+  { sri, ...manifest }: AssetsManifest,
   router: DataRouter
 ) {
   // Start with our matches for this pathname
@@ -64,6 +64,7 @@ export function getPartialManifest(
   return {
     ...manifest,
     routes: initialRoutes,
+    sri: sri ? true : undefined,
   };
 }
 

packages/react-router/lib/dom/ssr/routes-test-stub.tsx

@@ -100,6 +100,7 @@ export function createRoutesStub(
     if (routerRef.current == null) {
       remixContextRef.current = {
         future: {
+          unstable_subResourceIntegrity: future?.unstable_subResourceIntegrity === true,
           unstable_middleware: future?.unstable_middleware === true,
         },
         manifest: {

playground/framework/app/root.tsx

@@ -1,15 +1,35 @@
-import { Links, Meta, Outlet, Scripts, ScrollRestoration } from "react-router";
+import {
+  Link,
+  Links,
+  Meta,
+  Outlet,
+  Scripts,
+  ScrollRestoration,
+} from "react-router";
 
 export function Layout({ children }: { children: React.ReactNode }) {
   return (
     <html lang="en">
       <head>
         <meta charSet="utf-8" />
         <meta name="viewport" content="width=device-width, initial-scale=1" />
+
         <Meta />
         <Links />
       </head>
       <body>
+        <ul>
+          <li>
+            <Link prefetch="intent" to="/">
+              Home
+            </Link>
+          </li>
+          <li>
+            <Link prefetch="intent" to="/products/abc">
+              Product
+            </Link>
+          </li>
+        </ul>
         {children}
         <ScrollRestoration />
         <Scripts />

playground/framework/react-router.config.ts

@@ -1,3 +1,7 @@
 import type { Config } from "@react-router/dev/config";
 
-export default {} satisfies Config;
+export default {
+  future: {
+    unstable_subResourceIntegrity: true,
+  },
+} satisfies Config;