fix: handle trailing slash

Author: ascorbic

packages/runtime/src/templates/edge-shared/nextConfig.json

@@ -0,0 +1,3 @@
+{
+  "trailingSlash": true
+}

packages/runtime/src/templates/edge-shared/rsc-data.ts

@@ -6,7 +6,10 @@ interface PrerenderedRoute {
   dataRoute: string | null
 }
 
-export const getRscDataRouter = (prerenderedRoutes: Record<string, PrerenderedRoute>): EdgeFunction => {
+export const getRscDataRouter = (
+  prerenderedRoutes: Record<string, PrerenderedRoute>,
+  trailingSlash: boolean,
+): EdgeFunction => {
   const routeEntries: Array<[string, PrerenderedRoute]> = Object.entries(prerenderedRoutes)
   const routes = new Map(routeEntries)
 
@@ -30,8 +33,8 @@ export const getRscDataRouter = (prerenderedRoutes: Record<string, PrerenderedRo
       const route = routes.get(pathname)
       if (route?.dataRoute) {
         log('Rewriting to data route', route.dataRoute)
-        // Set the original route, without the trimmed slash
-        request.headers.set('x-rsc-route', url.pathname)
+        // We need the correct slash here so we don't get a 308
+        request.headers.set('x-rsc-route', trailingSlash ? `${pathname}/` : pathname)
         return context.rewrite(new URL(route.dataRoute, request.url))
       }
     } else if (rscDataRoutes.has(pathname)) {

packages/runtime/src/templates/edge/rsc-data.ts

@@ -1,5 +1,6 @@
 import prerenderManifest from '../edge-shared/prerender-manifest.json' assert { type: 'json' }
+import nextConfig from '../edge-shared/nextConfig.json' assert { type: 'json' }
 import { getRscDataRouter } from '../edge-shared/rsc-data.ts'
 
-const handler = getRscDataRouter(prerenderManifest.routes)
+const handler = getRscDataRouter(prerenderManifest.routes, nextConfig.trailingSlash)
 export default handler