fix(ssr): inline middleware during the build, not rely on file system

.changeset/large-bugs-matter.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Correctly retrive middleware when using it in SSR enviroments.

packages/astro/src/core/app/index.ts

@@ -56,8 +56,6 @@ export class App {
 	});
 	#baseWithoutTrailingSlash: string;
 	#pipeline: SSRRoutePipeline;
-	#onRequest: MiddlewareEndpointHandler | undefined;
-	#middlewareLoaded: boolean;
 	#adapterLogger: AstroIntegrationLogger;
 
 	constructor(manifest: SSRManifest, streaming = true) {
@@ -68,7 +66,6 @@ export class App {
 		this.#routeDataToRouteInfo = new Map(manifest.routes.map((route) => [route.routeData, route]));
 		this.#baseWithoutTrailingSlash = removeTrailingForwardSlash(this.#manifest.base);
 		this.#pipeline = new SSRRoutePipeline(this.#createEnvironment(streaming));
-		this.#middlewareLoaded = false;
 		this.#adapterLogger = new AstroIntegrationLogger(
 			this.#logger.options,
 			this.#manifest.adapterName
@@ -137,20 +134,7 @@ export class App {
 		return routeData;
 	}
 
-	async #getOnRequest() {
-		if (this.#manifest.middlewareEntryPoint && !this.#middlewareLoaded) {
-			try {
-				const middleware = await import(this.#manifest.middlewareEntryPoint);
-				this.#pipeline.setMiddlewareFunction(middleware.onRequest as MiddlewareEndpointHandler);
-			} catch (e) {
-				this.#logger.warn('SSR', "Couldn't load the middleware entry point");
-			}
-		}
-		this.#middlewareLoaded = true;
-	}
-
 	async render(request: Request, routeData?: RouteData, locals?: object): Promise<Response> {
-		await this.#getOnRequest();
 		// Handle requests with duplicate slashes gracefully by cloning with a cleaned-up request URL
 		if (request.url !== collapseDuplicateSlashes(request.url)) {
 			request = new Request(collapseDuplicateSlashes(request.url), request);
@@ -178,6 +162,9 @@ export class App {
 		);
 		let response;
 		try {
+			if (mod.onRequest) {
+				this.#pipeline.setMiddlewareFunction(mod.onRequest as MiddlewareEndpointHandler);
+			}
 			response = await this.#pipeline.renderRoute(renderContext, pageModule);
 		} catch (err: any) {
 			if (err instanceof EndpointNotFoundError) {
@@ -295,6 +282,9 @@ export class App {
 					status
 				);
 				const page = (await mod.page()) as any;
+				if (mod.onRequest) {
+					this.#pipeline.setMiddlewareFunction(mod.onRequest as MiddlewareEndpointHandler);
+				}
 				const response = await this.#pipeline.renderRoute(newRenderContext, page);
 				return this.#mergeResponses(response, originalResponse);
 			} catch {}
@@ -319,7 +309,7 @@ export class App {
 
 		const { statusText, headers } = oldResponse;
 
-		// If the the new response did not have a meaningful status, an override may have been provided
+		// If the new response did not have a meaningful status, an override may have been provided
 		// If the original status was 200 (default), override it with the new status (probably 404 or 500)
 		// Otherwise, the user set a specific status while rendering and we should respect that one
 		const status = override?.status

packages/astro/src/core/app/types.ts

@@ -49,7 +49,6 @@ export type SSRManifest = {
 	componentMetadata: SSRResult['componentMetadata'];
 	pageModule?: SinglePageBuiltModule;
 	pageMap?: Map<ComponentPath, ImportComponentInstance>;
-	middlewareEntryPoint: string | undefined;
 };
 
 export type SerializedSSRManifest = Omit<

packages/astro/src/core/build/buildPipeline.ts

@@ -78,13 +78,6 @@ export class BuildPipeline extends Pipeline {
 		return this.#manifest;
 	}
 
-	async retrieveMiddlewareFunction() {
-		if (this.#internals.middlewareEntryPoint) {
-			const middleware = await import(this.#internals.middlewareEntryPoint.toString());
-			this.setMiddlewareFunction(middleware.onRequest);
-		}
-	}
-
 	getLogger(): Logger {
 		return this.getEnvironment().logger;
 	}

packages/astro/src/core/build/generate.ts

@@ -10,6 +10,7 @@ import type {
 	ComponentInstance,
 	GetStaticPathsItem,
 	ImageTransform,
+	MiddlewareEndpointHandler,
 	RouteData,
 	RouteType,
 	SSRError,
@@ -135,7 +136,7 @@ export async function generatePages(opts: StaticBuildOptions, internals: BuildIn
 		);
 	}
 	const pipeline = new BuildPipeline(opts, internals, manifest);
-	await pipeline.retrieveMiddlewareFunction();
+
 	const outFolder = ssr
 		? opts.settings.config.build.server
 		: getOutDirWithinCwd(opts.settings.config.outDir);
@@ -247,7 +248,10 @@ async function generatePage(
 		.reduce(mergeInlineCss, []);
 
 	const pageModulePromise = ssrEntry.page;
-
+	const onRequest = ssrEntry.onRequest;
+	if (onRequest) {
+		pipeline.setMiddlewareFunction(onRequest as MiddlewareEndpointHandler);
+	}
 	if (!pageModulePromise) {
 		throw new Error(
 			`Unable to find the module for ${pageData.component}. This is unexpected and likely a bug in Astro, please report.`
@@ -604,8 +608,5 @@ export function createBuildManifest(
 			? new URL(settings.config.base, settings.config.site).toString()
 			: settings.config.site,
 		componentMetadata: internals.componentMetadata,
-		middlewareEntryPoint: internals.middlewareEntryPoint
-			? internals.middlewareEntryPoint.toString()
-			: undefined,
 	};
 }

packages/astro/src/core/build/plugins/plugin-manifest.ts

@@ -237,9 +237,6 @@ function buildManifest(
 		// Set this to an empty string so that the runtime knows not to try and load this.
 		entryModules[BEFORE_HYDRATION_SCRIPT_ID] = '';
 	}
-	const isEdgeMiddleware =
-		// TODO: remove in Astro 4.0
-		settings.config.build.excludeMiddleware || settings.adapter?.adapterFeatures?.edgeMiddleware;
 
 	const ssrManifest: SerializedSSRManifest = {
 		adapterName: opts.settings.adapter?.name ?? '',
@@ -253,9 +250,6 @@ function buildManifest(
 		clientDirectives: Array.from(settings.clientDirectives),
 		entryModules,
 		assets: staticFiles.map(prefixAssetPath),
-		middlewareEntryPoint: !isEdgeMiddleware
-			? internals.middlewareEntryPoint?.toString()
-			: undefined,
 	};
 
 	return ssrManifest;

packages/astro/src/core/build/types.ts

@@ -4,6 +4,7 @@ import type {
 	AstroSettings,
 	ComponentInstance,
 	ManifestData,
+	MiddlewareHandler,
 	RouteData,
 	RuntimeMode,
 	SSRLoadedRenderer,
@@ -51,6 +52,7 @@ export interface SinglePageBuiltModule {
 	/**
 	 * The `onRequest` hook exported by the middleware
 	 */
+	onRequest?: MiddlewareHandler<unknown>;
 	renderers: SSRLoadedRenderer[];
 }
 

packages/astro/src/core/redirects/component.ts

@@ -12,5 +12,6 @@ export const RedirectComponentInstance: ComponentInstance = {
 
 export const RedirectSinglePageBuiltModule: SinglePageBuiltModule = {
 	page: () => Promise.resolve(RedirectComponentInstance),
+	onRequest: (_, next) => next(),
 	renderers: [],
 };

packages/astro/src/vite-plugin-astro-server/plugin.ts

@@ -99,6 +99,5 @@ export function createDevelopmentManifest(settings: AstroSettings): SSRManifest
 			? new URL(settings.config.base, settings.config.site).toString()
 			: settings.config.site,
 		componentMetadata: new Map(),
-		middlewareEntryPoint: undefined,
 	};
 }

packages/integrations/vercel/test/edge-middleware.test.js

@@ -19,7 +19,7 @@ describe('Vercel edge middleware', () => {
 	});
 
 	// TODO: The path here seems to be inconsistent?
-	it.skip('with edge handle file, should successfully build the middleware', async () => {
+	it.skip('without edge handle file, should successfully build the middleware', async () => {
 		const fixture = await loadFixture({
 			root: './fixtures/middleware-without-edge-file/',
 		});