Add tests for _headers and _redirects in preview (#8496)

* Put middleware at front of chain in preview mode

* Add tests for _headers and _redirects in build/preview

Author: jamesopstad

packages/vite-plugin-cloudflare/playground/__test-utils__/responses.ts

@@ -17,7 +17,7 @@ export async function getJsonResponse(
 	}
 }
 
-async function getResponse(path = "/") {
+export async function getResponse(path = "/") {
 	const url = `${viteTestUrl}${path}`;
 
 	const response = page.waitForResponse(url);

packages/vite-plugin-cloudflare/playground/static-mpa/__tests__/assets.spec.ts

@@ -1,5 +1,11 @@
-import { expect, test } from "vitest";
-import { page, serverLogs, viteTestUrl } from "../../__test-utils__";
+import { describe, expect, test } from "vitest";
+import {
+	getResponse,
+	isBuild,
+	page,
+	serverLogs,
+	viteTestUrl,
+} from "../../__test-utils__";
 
 test("returns the correct home page", async () => {
 	const content = await page.textContent("h1");
@@ -39,3 +45,37 @@ test("returns the correct nested 404 page", async () => {
 test("worker configs warnings are not present in the terminal", async () => {
 	expect(serverLogs.warns).toEqual([]);
 });
+
+describe.runIf(isBuild)("_headers", () => {
+	test("applies exact headers", async () => {
+		const response = await getResponse("/contact");
+		const header = await response.headerValue("X-Header");
+		expect(header).toBe("exact-header");
+	});
+
+	test("applies splat headers", async () => {
+		const response = await getResponse("/vite.svg");
+		const header = await response.headerValue("X-Header");
+		expect(header).toBe("splat-header");
+	});
+});
+
+describe.runIf(isBuild)("_redirects", () => {
+	test("applies exact redirects", async () => {
+		await page.goto(`${viteTestUrl}/home`);
+		const content = await page.textContent("h1");
+		expect(content).toBe("Home");
+	});
+
+	test("applies splat redirects", async () => {
+		await page.goto(`${viteTestUrl}/contact/random-page`);
+		const content = await page.textContent("h1");
+		expect(content).toBe("Contact");
+	});
+
+	test("applies redirects if an asset exists at the 'from' path", async () => {
+		await page.goto(`${viteTestUrl}/text-file.txt`);
+		const content = await page.textContent("h1");
+		expect(content).toBe("Home");
+	});
+});

packages/vite-plugin-cloudflare/playground/static-mpa/public/_headers

@@ -0,0 +1,5 @@
+/contact
+	X-Header: exact-header
+
+/*.svg
+	X-Header: splat-header

packages/vite-plugin-cloudflare/playground/static-mpa/public/_redirects

@@ -0,0 +1,3 @@
+/home /
+/text-file.txt /
+/contact/* /contact

packages/vite-plugin-cloudflare/playground/static-mpa/public/text-file.txt

@@ -0,0 +1 @@
+Text content

packages/vite-plugin-cloudflare/src/index.ts

@@ -304,11 +304,10 @@ export function cloudflare(pluginConfig: PluginConfig = {}): vite.Plugin[] {
 
 				handleWebSocket(vitePreviewServer.httpServer, miniflare.dispatchFetch);
 
-				return () => {
-					vitePreviewServer.middlewares.use((req, res, next) => {
-						middleware(req, res, next);
-					});
-				};
+				// In preview mode we put our middleware at the front of the chain so that all assets are handled in Miniflare
+				vitePreviewServer.middlewares.use((req, res, next) => {
+					middleware(req, res, next);
+				});
 			},
 		},
 		// Plugin to support `CompiledWasm` modules