Support for prerendering in the Cloudflare integration (#5993)

* Cloudflare prerender branch

* Add prerendered routes to Cloudflare routes.json

* Adding changeset

* Prevent process proxy from running during prerender phase

11 files changed, 93 insertions, 6 deletions

diff --git a/.changeset/good-avocados-repeat.md b/.changeset/good-avocados-repeat.md
new file mode 100644
index 000000000..3ff9846de
--- /dev/null
+++ b/.changeset/good-avocados-repeat.md
@@ -0,0 +1,7 @@
+---
+'@astrojs/cloudflare': patch
+---
+
+Support for prerendering in the Cloudflare integration
+
+This fixes prerendering in the Cloudflare adapter. Now any prerendered routes are added to the `_routes.json` config so that the worker script is skipped for those routes.
diff --git a/packages/integrations/cloudflare/src/index.ts b/packages/integrations/cloudflare/src/index.ts
index 1df284fbb..3a077c4d6 100644
--- a/packages/integrations/cloudflare/src/index.ts
+++ b/packages/integrations/cloudflare/src/index.ts
@@ -49,7 +49,7 @@ export default function createIntegration(args?: Options): AstroIntegration {
 					build: {
 						client: new URL(`.${config.base}`, config.outDir),
 						server: new URL(`.${SERVER_BUILD_FOLDER}`, config.outDir),
-						serverEntry: '_worker.js',
+						serverEntry: '_worker.mjs',
 					},
 				});
 			},
@@ -88,10 +88,11 @@ export default function createIntegration(args?: Options): AstroIntegration {
 					vite.ssr.target = vite.ssr.target || 'webworker';
 				}
 			},
-			'astro:build:done': async () => {
+			'astro:build:done': async ({ pages }) => {
 				const entryPath = fileURLToPath(new URL(_buildConfig.serverEntry, _buildConfig.server)),
 					entryUrl = new URL(_buildConfig.serverEntry, _config.outDir),
 					buildPath = fileURLToPath(entryUrl);
+
 				await esbuild.build({
 					target: 'es2020',
 					platform: 'browser',
@@ -106,6 +107,9 @@ export default function createIntegration(args?: Options): AstroIntegration {
 					},
 				});
 
+				// Rename to worker.js
+				await fs.promises.rename(buildPath, buildPath.replace(/\.mjs$/, '.js'));
+
 				// throw the server folder in the bin
 				const serverUrl = new URL(_buildConfig.server);
 				await fs.promises.rm(serverUrl, { recursive: true, force: true });
@@ -143,6 +147,10 @@ export default function createIntegration(args?: Options): AstroIntegration {
 						.filter((file: string) => cloudflareSpecialFiles.indexOf(file) < 0)
 						.map((file: string) => `/${file}`);
 
+					for(let page of pages) {
+						staticPathList.push(prependForwardSlash(page.pathname));
+					}
+
 					const redirectsExists = await fs.promises
 						.stat(new URL('./_redirects', _config.outDir))
 						.then((stat) => stat.isFile())
@@ -202,3 +210,7 @@ export default function createIntegration(args?: Options): AstroIntegration {
 		},
 	};
 }
+
+function prependForwardSlash(path: string) {
+	return path[0] === '/' ? path : '/' + path;
+}
diff --git a/packages/integrations/cloudflare/src/server.advanced.ts b/packages/integrations/cloudflare/src/server.advanced.ts
index b57a480f9..3d6b4fbcd 100644
--- a/packages/integrations/cloudflare/src/server.advanced.ts
+++ b/packages/integrations/cloudflare/src/server.advanced.ts
@@ -1,8 +1,10 @@
 import type { SSRManifest } from 'astro';
 import { App } from 'astro/app';
-import { getProcessEnvProxy } from './util.js';
+import { getProcessEnvProxy, isNode } from './util.js';
 
-process.env = getProcessEnvProxy();
+if(!isNode) {
+	process.env = getProcessEnvProxy();
+}
 
 type Env = {
 	ASSETS: { fetch: (req: Request) => Promise<Response> };
diff --git a/packages/integrations/cloudflare/src/server.directory.ts b/packages/integrations/cloudflare/src/server.directory.ts
index 8f1b3b8ab..17a35f15a 100644
--- a/packages/integrations/cloudflare/src/server.directory.ts
+++ b/packages/integrations/cloudflare/src/server.directory.ts
@@ -1,8 +1,10 @@
 import type { SSRManifest } from 'astro';
 import { App } from 'astro/app';
-import { getProcessEnvProxy } from './util.js';
+import { getProcessEnvProxy, isNode } from './util.js';
 
-process.env = getProcessEnvProxy();
+if(!isNode) {
+	process.env = getProcessEnvProxy();
+}
 
 export function createExports(manifest: SSRManifest) {
 	const app = new App(manifest);
diff --git a/packages/integrations/cloudflare/src/util.ts b/packages/integrations/cloudflare/src/util.ts
index a44780863..96927e57a 100644
--- a/packages/integrations/cloudflare/src/util.ts
+++ b/packages/integrations/cloudflare/src/util.ts
@@ -1,3 +1,5 @@
+export const isNode = typeof process === 'object' && Object.prototype.toString.call(process) === '[object process]';
+
 export function getProcessEnvProxy() {
 	return new Proxy(
 		{},
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender/astro.config.mjs b/packages/integrations/cloudflare/test/fixtures/prerender/astro.config.mjs
new file mode 100644
index 000000000..bf47a0a33
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender/astro.config.mjs
@@ -0,0 +1,7 @@
+import { defineConfig } from 'astro/config';
+import cloudflare from '@astrojs/cloudflare';
+
+export default defineConfig({
+	adapter: cloudflare(),
+	output: 'server',
+});
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender/package.json b/packages/integrations/cloudflare/test/fixtures/prerender/package.json
new file mode 100644
index 000000000..3b2c5fef5
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "@test/astro-cloudflare-prerender",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "@astrojs/cloudflare": "workspace:*",
+    "astro": "workspace:*"
+  }
+}
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender/src/pages/index.astro b/packages/integrations/cloudflare/test/fixtures/prerender/src/pages/index.astro
new file mode 100644
index 000000000..dfd71c3de
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender/src/pages/index.astro
@@ -0,0 +1,8 @@
+<html>
+<head>
+	<title>Testing</title>
+</head>
+<body>
+	<h1>Testing</h1>
+</body>
+</html>
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender/src/pages/one.astro b/packages/integrations/cloudflare/test/fixtures/prerender/src/pages/one.astro
new file mode 100644
index 000000000..30386a625
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender/src/pages/one.astro
@@ -0,0 +1,11 @@
+---
+export const prerender = true;
+---
+<html>
+<head>
+	<title>Testing</title>
+</head>
+<body>
+	<h1>Testing</h1>
+</body>
+</html>
diff --git a/packages/integrations/cloudflare/test/prerender.test.js b/packages/integrations/cloudflare/test/prerender.test.js
new file mode 100644
index 000000000..a3ce50d08
--- /dev/null
+++ b/packages/integrations/cloudflare/test/prerender.test.js
@@ -0,0 +1,19 @@
+import { loadFixture } from './test-utils.js';
+import { expect } from 'chai';
+
+describe('Prerendering', () => {
+	/** @type {import('./test-utils').Fixture} */
+	let fixture;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: './fixtures/prerender/',
+		});
+		await fixture.build();
+	});
+
+	it('includes prerendered routes in the routes.json config', async () => {
+		const routes = JSON.parse(await fixture.readFile('/_routes.json'));
+		expect(routes.exclude).to.include('/one/');
+	});
+});
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 454931ff2..c3b3920a8 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -2645,6 +2645,14 @@ importers:
       '@astrojs/cloudflare': link:../../..
       astro: link:../../../../../astro
 
+  packages/integrations/cloudflare/test/fixtures/prerender:
+    specifiers:
+      '@astrojs/cloudflare': workspace:*
+      astro: workspace:*
+    dependencies:
+      '@astrojs/cloudflare': link:../../..
+      astro: link:../../../../../astro
+
   packages/integrations/deno:
     specifiers:
       astro: workspace:*