fix(intergration defined middleware): prevent importing non-existent user middleware

.changeset/clean-cars-drive.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes an issue where integration defined middleware failed when user defined middleware was not present.

packages/astro/src/core/middleware/vite-plugin.ts

@@ -59,19 +59,29 @@ export function vitePluginMiddleware({ settings }: { settings: AstroSettings }):
 
 				const preMiddleware = createMiddlewareImports(settings.middlewares.pre, 'pre');
 				const postMiddleware = createMiddlewareImports(settings.middlewares.post, 'post');
+				const userMiddleware = {
+					importsCode: resolvedMiddlewareId ? `import { onRequest as userOnRequest } from '${resolvedMiddlewareId}';` : undefined,
+					sequenceCode: resolvedMiddlewareId ? 'userOnRequest' : undefined
+				};
+
+				const importsCode = [
+					preMiddleware.importsCode,
+					userMiddleware.importsCode,
+					postMiddleware.importsCode
+				].filter(Boolean).join('\n');
+
+				const sequenceCode = [
+					preMiddleware.sequenceCode,
+					userMiddleware.sequenceCode,
+					postMiddleware.sequenceCode
+				].filter(Boolean).join(', ');
 
 				const source = `
-import { onRequest as userOnRequest } from '${resolvedMiddlewareId}';
 import { sequence } from 'astro:middleware';
-${preMiddleware.importsCode}${postMiddleware.importsCode}
+${importsCode}
 
-export const onRequest = sequence(
-	${preMiddleware.sequenceCode}${preMiddleware.sequenceCode ? ',' : ''}
-	userOnRequest${postMiddleware.sequenceCode ? ',' : ''}
-	${postMiddleware.sequenceCode}
-);
+export const onRequest = sequence(${sequenceCode});
 `.trim();
-
 				return source;
 			}
 		},

packages/astro/test/fixtures/middleware-from-integration/astro.config.mjs

@@ -0,0 +1,23 @@
+import { defineConfig } from 'astro/config';
+import { fileURLToPath } from 'node:url';
+
+export default defineConfig({
+	integrations: [
+		{
+			name: 'my-middleware',
+			hooks: {
+				'astro:config:setup':({ addMiddleware }) => {
+					addMiddleware({
+						entrypoint: fileURLToPath(new URL('./integration-middleware-pre.js', import.meta.url)),
+						order: 'pre'
+					});
+
+					addMiddleware({
+						entrypoint: fileURLToPath(new URL('./integration-middleware-post.js', import.meta.url)),
+						order: 'post'
+					});
+				}
+			}
+		}
+	]
+});

packages/astro/test/fixtures/middleware-from-integration/integration-middleware-post.js

@@ -0,0 +1,13 @@
+import { sequence, defineMiddleware } from 'astro:middleware';
+
+export const onRequest = defineMiddleware((context, next) => {
+	if(context.url.pathname === '/integration-post') {
+		return new Response(JSON.stringify({ post: 'works' }), {
+			headers: {
+				'content-type': 'application/json'
+			}
+		});
+	}
+
+	return next();
+});

packages/astro/test/fixtures/middleware-from-integration/integration-middleware-pre.js

@@ -0,0 +1,13 @@
+import { sequence, defineMiddleware } from 'astro:middleware';
+
+export const onRequest = defineMiddleware((context, next) => {
+	if(context.url.pathname === '/integration-pre') {
+		return new Response(JSON.stringify({ pre: 'works' }), {
+			headers: {
+				'content-type': 'application/json'
+			}
+		});
+	}
+
+	return next();
+});

packages/astro/test/fixtures/middleware-from-integration/package.json

@@ -0,0 +1,8 @@
+{
+  "name": "@test/middleware-from-integration",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "astro": "workspace:*"
+  }
+}

packages/astro/test/fixtures/middleware-from-integration/src/pages/404.astro

@@ -0,0 +1 @@
+<p>404.astro allows the middleware to run for every request</p>

packages/astro/test/middleware.test.js

@@ -101,6 +101,37 @@ describe('Middleware in DEV mode', () => {
 	});
 });
 
+describe('Integration hooks', () => {
+
+	/** @type {import('./test-utils').Fixture} */
+	let fixture;
+
+	/** @type {import('../src/core/app/index').App} */
+	let app;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: './fixtures/middleware-from-integration/',
+			output: 'server',
+			adapter: testAdapter({}),
+		});
+		await fixture.build();
+		app = await fixture.loadTestAdapterApp();
+	});
+
+	it('Integration middleware marked as "pre" runs', async () => {
+		let res = await app.render(new Request('http://example.com/integration-pre'));
+		let json = await res.json();
+		expect(json.pre).to.equal('works');
+	});
+
+	it('Integration middleware marked as "post" runs', async () => {
+		let res = await app.render(new Request('http://example.com/integration-post'));
+		let json = await res.json();
+		expect(json.post).to.equal('works');
+	});
+})
+
 describe('Middleware in PROD mode, SSG', () => {
 	/** @type {import('./test-utils').Fixture} */
 	let fixture;