fix: correctly emit middleware file name (#7427)

10 files changed, 47 insertions, 28 deletions

diff --git a/.changeset/great-crabs-march.md b/.changeset/great-crabs-march.md
new file mode 100644
index 000000000..5f58b2bb4
--- /dev/null
+++ b/.changeset/great-crabs-march.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Correctly emit the middleware code during the build phase. The file emitted is now `dist/middleware.mjs`
diff --git a/packages/astro/src/core/app/index.ts b/packages/astro/src/core/app/index.ts
index 56d22eafc..d9926f70c 100644
--- a/packages/astro/src/core/app/index.ts
+++ b/packages/astro/src/core/app/index.ts
@@ -236,12 +236,11 @@ export class App {
 				site: this.#env.site,
 				adapterName: this.#env.adapterName,
 			});
-			const onRequest = page.middleware?.onRequest;
 			let response;
-			if (onRequest) {
+			if (page.onRequest) {
 				response = await callMiddleware<Response>(
 					this.#env.logging,
-					onRequest as MiddlewareResponseHandler,
+					page.onRequest as MiddlewareResponseHandler,
 					apiContext,
 					() => {
 						return renderPage({ mod, renderContext, env: this.#env, apiContext });
@@ -287,7 +286,7 @@ export class App {
 			mod: handler as any,
 		});
 
-		const result = await callEndpoint(handler, this.#env, ctx, this.#logging, page.middleware);
+		const result = await callEndpoint(handler, this.#env, ctx, this.#logging, page.onRequest);
 
 		if (result.type === 'response') {
 			if (result.response.headers.get('X-Astro-Response') === 'Not-Found') {
diff --git a/packages/astro/src/core/build/generate.ts b/packages/astro/src/core/build/generate.ts
index a6a1ece54..8fe090fc1 100644
--- a/packages/astro/src/core/build/generate.ts
+++ b/packages/astro/src/core/build/generate.ts
@@ -12,6 +12,7 @@ import type {
 	EndpointOutput,
 	GetStaticPathsItem,
 	ImageTransform,
+	MiddlewareHandler,
 	MiddlewareResponseHandler,
 	RouteData,
 	RouteType,
@@ -229,7 +230,7 @@ async function generatePage(
 		.reduce(mergeInlineCss, []);
 
 	const pageModulePromise = ssrEntry.page;
-	const middleware = ssrEntry.middleware;
+	const onRequest = ssrEntry.onRequest;
 
 	if (!pageModulePromise) {
 		throw new Error(
@@ -264,7 +265,7 @@ async function generatePage(
 
 	for (let i = 0; i < paths.length; i++) {
 		const path = paths[i];
-		await generatePath(path, opts, generationOptions, middleware);
+		await generatePath(path, opts, generationOptions, onRequest);
 		const timeEnd = performance.now();
 		const timeChange = getTimeStat(timeStart, timeEnd);
 		const timeIncrease = `(+${timeChange})`;
@@ -448,7 +449,7 @@ async function generatePath(
 	pathname: string,
 	opts: StaticBuildOptions,
 	gopts: GeneratePathOptions,
-	middleware?: AstroMiddlewareInstance<unknown>
+	onRequest?: MiddlewareHandler<unknown>
 ) {
 	const { settings, logging, origin, routeCache } = opts;
 	const {
@@ -569,7 +570,7 @@ async function generatePath(
 			env,
 			renderContext,
 			logging,
-			middleware as AstroMiddlewareInstance<Response | EndpointOutput>
+			onRequest as MiddlewareHandler<Response | EndpointOutput>
 		);
 
 		if (result.type === 'response') {
@@ -593,7 +594,6 @@ async function generatePath(
 				adapterName: env.adapterName,
 			});
 
-			const onRequest = middleware?.onRequest;
 			if (onRequest) {
 				response = await callMiddleware<Response>(
 					env.logging,
diff --git a/packages/astro/src/core/build/plugins/plugin-middleware.ts b/packages/astro/src/core/build/plugins/plugin-middleware.ts
index 6bd63b44f..e65a112dd 100644
--- a/packages/astro/src/core/build/plugins/plugin-middleware.ts
+++ b/packages/astro/src/core/build/plugins/plugin-middleware.ts
@@ -3,9 +3,12 @@ import { MIDDLEWARE_PATH_SEGMENT_NAME } from '../../constants.js';
 import type { BuildInternals } from '../internal.js';
 import type { AstroBuildPlugin } from '../plugin';
 import type { StaticBuildOptions } from '../types';
+import { addRollupInput } from '../add-rollup-input.js';
 
 export const MIDDLEWARE_MODULE_ID = '@astro-middleware';
 
+const EMPTY_MIDDLEWARE = '\0empty-middleware';
+
 export function vitePluginMiddleware(
 	opts: StaticBuildOptions,
 	_internals: BuildInternals
@@ -13,6 +16,10 @@ export function vitePluginMiddleware(
 	return {
 		name: '@astro/plugin-middleware',
 
+		options(options) {
+			return addRollupInput(options, [MIDDLEWARE_MODULE_ID]);
+		},
+
 		async resolveId(id) {
 			if (id === MIDDLEWARE_MODULE_ID) {
 				const middlewareId = await this.resolve(
@@ -20,8 +27,19 @@ export function vitePluginMiddleware(
 				);
 				if (middlewareId) {
 					return middlewareId.id;
+				} else {
+					return EMPTY_MIDDLEWARE;
 				}
 			}
+			if (id === EMPTY_MIDDLEWARE) {
+				return EMPTY_MIDDLEWARE;
+			}
+		},
+
+		load(id) {
+			if (id === EMPTY_MIDDLEWARE) {
+				return 'export const onRequest = undefined';
+			}
 		},
 	};
 }
diff --git a/packages/astro/src/core/build/plugins/plugin-pages.ts b/packages/astro/src/core/build/plugins/plugin-pages.ts
index f767a9c5b..c6f89a558 100644
--- a/packages/astro/src/core/build/plugins/plugin-pages.ts
+++ b/packages/astro/src/core/build/plugins/plugin-pages.ts
@@ -82,8 +82,8 @@ function vitePluginPages(opts: StaticBuildOptions, internals: BuildInternals): V
 
 						const middlewareModule = await this.resolve(MIDDLEWARE_MODULE_ID);
 						if (middlewareModule) {
-							imports.push(`import * as middleware from "${middlewareModule.id}";`);
-							exports.push(`export { middleware };`);
+							imports.push(`import { onRequest } from "${middlewareModule.id}";`);
+							exports.push(`export { onRequest };`);
 						}
 
 						return `${imports.join('\n')}${exports.join('\n')}`;
diff --git a/packages/astro/src/core/build/static-build.ts b/packages/astro/src/core/build/static-build.ts
index 647b31983..48f70a15e 100644
--- a/packages/astro/src/core/build/static-build.ts
+++ b/packages/astro/src/core/build/static-build.ts
@@ -32,6 +32,7 @@ import { RESOLVED_RENDERERS_MODULE_ID } from './plugins/plugin-renderers.js';
 import { SSR_VIRTUAL_MODULE_ID } from './plugins/plugin-ssr.js';
 import type { AllPagesData, PageBuildData, StaticBuildOptions } from './types';
 import { getTimeStat } from './util.js';
+import { MIDDLEWARE_MODULE_ID } from './plugins/plugin-middleware.js';
 
 export async function viteBuild(opts: StaticBuildOptions) {
 	const { allPages, settings } = opts;
@@ -176,12 +177,7 @@ async function ssrBuild(
 					entryFileNames(chunkInfo) {
 						if (chunkInfo.facadeModuleId?.startsWith(ASTRO_PAGE_RESOLVED_MODULE_ID)) {
 							return makeAstroPageEntryPointFileName(chunkInfo.facadeModuleId, allPages);
-						} else if (
-							// checks if the path of the module we have middleware, e.g. middleware.js / middleware/index.js
-							chunkInfo.moduleIds.find((m) => m.includes('middleware')) !== undefined &&
-							// checks if the file actually export the `onRequest` function
-							chunkInfo.exports.includes('_middleware')
-						) {
+						} else if (chunkInfo.facadeModuleId === MIDDLEWARE_MODULE_ID) {
 							return 'middleware.mjs';
 						} else if (chunkInfo.facadeModuleId === SSR_VIRTUAL_MODULE_ID) {
 							return opts.settings.config.build.serverEntry;
diff --git a/packages/astro/src/core/build/types.ts b/packages/astro/src/core/build/types.ts
index 772235697..8409a8cff 100644
--- a/packages/astro/src/core/build/types.ts
+++ b/packages/astro/src/core/build/types.ts
@@ -6,6 +6,7 @@ import type {
 	BuildConfig,
 	ComponentInstance,
 	ManifestData,
+	MiddlewareHandler,
 	RouteData,
 	RuntimeMode,
 	SSRLoadedRenderer,
@@ -51,7 +52,10 @@ type ImportComponentInstance = () => Promise<ComponentInstance>;
 
 export interface SinglePageBuiltModule {
 	page: ImportComponentInstance;
-	middleware: AstroMiddlewareInstance<unknown>;
+	/**
+	 * The `onRequest` hook exported by the middleware
+	 */
+	onRequest?: MiddlewareHandler<unknown>;
 	renderers: SSRLoadedRenderer[];
 }
 
diff --git a/packages/astro/src/core/endpoint/dev/index.ts b/packages/astro/src/core/endpoint/dev/index.ts
index b82975476..04e11b578 100644
--- a/packages/astro/src/core/endpoint/dev/index.ts
+++ b/packages/astro/src/core/endpoint/dev/index.ts
@@ -21,5 +21,5 @@ export async function call(options: SSROptions, logging: LogOptions) {
 		mod: endpointHandler as any,
 	});
 
-	return await callEndpoint(endpointHandler, env, ctx, logging, middleware);
+	return await callEndpoint(endpointHandler, env, ctx, logging, middleware?.onRequest);
 }
diff --git a/packages/astro/src/core/endpoint/index.ts b/packages/astro/src/core/endpoint/index.ts
index 5822685cf..5390b97dd 100644
--- a/packages/astro/src/core/endpoint/index.ts
+++ b/packages/astro/src/core/endpoint/index.ts
@@ -5,6 +5,7 @@ import type {
 	EndpointHandler,
 	EndpointOutput,
 	MiddlewareEndpointHandler,
+	MiddlewareHandler,
 	Params,
 } from '../../@types/astro';
 import type { Environment, RenderContext } from '../render/index';
@@ -97,7 +98,7 @@ export async function callEndpoint<MiddlewareResult = Response | EndpointOutput>
 	env: Environment,
 	ctx: RenderContext,
 	logging: LogOptions,
-	middleware?: AstroMiddlewareInstance<MiddlewareResult> | undefined
+	onRequest?: MiddlewareHandler<MiddlewareResult> | undefined
 ): Promise<EndpointCallResult> {
 	const context = createAPIContext({
 		request: ctx.request,
@@ -108,11 +109,10 @@ export async function callEndpoint<MiddlewareResult = Response | EndpointOutput>
 	});
 
 	let response;
-	if (middleware && middleware.onRequest) {
-		const onRequest = middleware.onRequest as MiddlewareEndpointHandler;
+	if (onRequest) {
 		response = await callMiddleware<Response | EndpointOutput>(
 			env.logging,
-			onRequest,
+			onRequest as MiddlewareEndpointHandler,
 			context,
 			async () => {
 				return await renderEndpoint(mod, context, env.ssr);
diff --git a/packages/astro/src/core/redirects/component.ts b/packages/astro/src/core/redirects/component.ts
index f76b82517..fc6f07b54 100644
--- a/packages/astro/src/core/redirects/component.ts
+++ b/packages/astro/src/core/redirects/component.ts
@@ -1,5 +1,6 @@
 import type { AstroMiddlewareInstance, ComponentInstance } from '../../@types/astro';
 import type { SinglePageBuiltModule } from '../build/types';
+import type { MiddlewareHandler } from '../../@types/astro';
 
 // A stub of a component instance for a given route
 export const RedirectComponentInstance: ComponentInstance = {
@@ -10,12 +11,8 @@ export const RedirectComponentInstance: ComponentInstance = {
 	},
 };
 
-const StaticMiddlewareInstance: AstroMiddlewareInstance<unknown> = {
-	onRequest: (ctx, next) => next(),
-};
-
 export const RedirectSinglePageBuiltModule: SinglePageBuiltModule = {
 	page: () => Promise.resolve(RedirectComponentInstance),
-	middleware: StaticMiddlewareInstance,
+	onRequest: (ctx, next) => next(),
 	renderers: [],
 };