feat: turbopack support (#983)

Co-authored-by: Nicolas Dorseuil <nicolas@gitbook.io>

Author: vicb

.changeset/silver-phones-brush.md

@@ -0,0 +1,5 @@
+---
+"@opennextjs/cloudflare": minor
+---
+
+feat: turbopack support

examples/common/config-e2e.ts

@@ -27,9 +27,9 @@ export function configurePlaywright(
 		if (isCI) {
 			// Do not build on CI - there is a preceding build step
 			command = `pnpm preview:worker -- --port ${port} --inspector-port ${inspectorPort} ${env}`;
-			timeout = 200_000;
+			timeout = 800_000;
 		} else {
-			timeout = 500_000;
+			timeout = 800_000;
 			command = `pnpm preview -- --port ${port} --inspector-port ${inspectorPort} ${env}`;
 		}
 	} else {

examples/e2e/app-router/package.json

@@ -5,7 +5,7 @@
 	"scripts": {
 		"openbuild": "node ../../packages/open-next/dist/index.js build --streaming --build-command \"npx turbo build\"",
 		"dev": "next dev --turbopack --port 3001",
-		"build": "next build",
+		"build": "next build --turbopack",
 		"start": "next start --port 3001",
 		"lint": "next lint",
 		"clean": "rm -rf .turbo node_modules .next .open-next",

packages/cloudflare/src/cli/build/bundle-server.ts

@@ -50,15 +50,12 @@ export async function bundleServer(buildOpts: BuildOptions, projectOpts: Project
 	copyPackageCliFiles(packageDistDir, buildOpts);
 
 	const { appPath, outputDir, monorepoRoot, debug } = buildOpts;
-	const baseManifestPath = path.join(
-		outputDir,
-		"server-functions/default",
-		getPackagePath(buildOpts),
-		".next"
-	);
-	const serverFiles = path.join(baseManifestPath, "required-server-files.json");
+	const dotNextPath = path.join(outputDir, "server-functions/default", getPackagePath(buildOpts), ".next");
+	const serverFiles = path.join(dotNextPath, "required-server-files.json");
 	const nextConfig = JSON.parse(fs.readFileSync(serverFiles, "utf-8")).config;
 
+	const useTurbopack = fs.existsSync(path.join(dotNextPath, "server/chunks/[turbopack]_runtime.js"));
+
 	console.log(`\x1b[35m⚙️ Bundling the OpenNext server...\n\x1b[0m`);
 
 	await patchWebpackRuntime(buildOpts);
@@ -141,13 +138,12 @@ export async function bundleServer(buildOpts: BuildOptions, projectOpts: Project
 			// Note: we need the __non_webpack_require__ variable declared as it is used by next-server:
 			// https://github.com/vercel/next.js/blob/be0c3283/packages/next/src/server/next-server.ts#L116-L119
 			__non_webpack_require__: "require",
+			// The 2 following defines are used to reduce the bundle size by removing unnecessary code
+			// Next uses different precompiled renderers (i.e. `app-page.runtime.prod.js`) based on if you use `TURBOPACK` or some experimental React features
+			...(useTurbopack ? {} : { "process.env.TURBOPACK": "false" }),
 			// We make sure that environment variables that Next.js expects are properly defined
 			"process.env.NEXT_RUNTIME": '"nodejs"',
 			"process.env.NODE_ENV": '"production"',
-			// The 2 following defines are used to reduce the bundle size by removing unnecessary code
-			// Next uses different precompiled renderers (i.e. `app-page.runtime.prod.js`) based on if you use `TURBOPACK` or some experimental React features
-			// Turbopack is not supported for build at the moment, so we disable it
-			"process.env.TURBOPACK": "false",
 			// This define should be safe to use for Next 14.2+, earlier versions (13.5 and less) will cause trouble
 			"process.env.__NEXT_EXPERIMENTAL_REACT": `${needsExperimentalReact(nextConfig)}`,
 			// Fix `res.validate` in Next 15.4 (together with the `route-module` patch)

packages/cloudflare/src/cli/build/open-next/createServerBundle.ts

@@ -27,6 +27,7 @@ import type { Plugin } from "esbuild";
 
 import { getOpenNextConfig } from "../../../api/config.js";
 import { patchResRevalidate } from "../patches/plugins/res-revalidate.js";
+import { patchTurbopackRuntime } from "../patches/plugins/turbopack.js";
 import { patchUseCacheIO } from "../patches/plugins/use-cache.js";
 import { normalizePath } from "../utils/index.js";
 import { copyWorkerdPackages } from "../utils/workerd.js";
@@ -210,6 +211,7 @@ async function generateBundle(
 		// Cloudflare specific patches
 		patchResRevalidate,
 		patchUseCacheIO,
+		patchTurbopackRuntime,
 		...additionalCodePatches,
 	]);
 

packages/cloudflare/src/cli/build/patches/ast/patch-vercel-og-library.ts

@@ -24,6 +24,8 @@ export function patchVercelOgLibrary(buildOpts: BuildOptions) {
 	for (const traceInfoPath of globSync(path.join(appBuildOutputPath, ".next/server/**/*.nft.json"), {
 		windowsPathsNoEscape: true,
 	})) {
+		let edgeFilePatched = false;
+
 		const traceInfo: TraceInfo = JSON.parse(readFileSync(traceInfoPath, { encoding: "utf8" }));
 		const tracedNodePath = traceInfo.files.find((p) => p.endsWith("@vercel/og/index.node.js"));
 
@@ -40,17 +42,23 @@ export function patchVercelOgLibrary(buildOpts: BuildOptions) {
 			);
 
 			copyFileSync(tracedEdgePath, outputEdgePath);
+		}
 
+		if (!edgeFilePatched) {
+			edgeFilePatched = true;
 			// Change font fetches in the library to use imports.
 			const node = parseFile(outputEdgePath);
 			const { edits, matches } = patchVercelOgFallbackFont(node);
 			writeFileSync(outputEdgePath, node.commitEdits(edits));
 
-			const fontFileName = matches[0]!.getMatch("PATH")!.text();
-			renameSync(path.join(outputDir, fontFileName), path.join(outputDir, `${fontFileName}.bin`));
+			if (matches.length > 0) {
+				const fontFileName = matches[0]!.getMatch("PATH")!.text();
+				renameSync(path.join(outputDir, fontFileName), path.join(outputDir, `${fontFileName}.bin`));
+			}
 		}
 
 		// Change node imports for the library to edge imports.
+		// This is only useful when turbopack is not used to bundle the function.
 		const routeFilePath = traceInfoPath.replace(appBuildOutputPath, packagePath).replace(".nft.json", "");
 
 		const node = parseFile(routeFilePath);

packages/cloudflare/src/cli/build/patches/plugins/turbopack.ts

@@ -0,0 +1,89 @@
+import { patchCode } from "@opennextjs/aws/build/patch/astCodePatcher.js";
+import type { CodePatcher } from "@opennextjs/aws/build/patch/codePatcher.js";
+import { getCrossPlatformPathRegex } from "@opennextjs/aws/utils/regex.js";
+
+const inlineChunksRule = `
+rule:
+  kind: call_expression
+  pattern: require(resolved)
+fix:
+  requireChunk(chunkPath)
+`;
+
+export const patchTurbopackRuntime: CodePatcher = {
+	name: "inline-turbopack-chunks",
+	patches: [
+		{
+			versions: ">=15.0.0",
+			pathFilter: getCrossPlatformPathRegex(String.raw`\[turbopack\]_runtime\.js$`, {
+				escape: false,
+			}),
+			contentFilter: /loadRuntimeChunkPath/,
+			patchCode: async ({ code, tracedFiles }) => {
+				let patched = patchCode(code, inlineExternalImportRule);
+				patched = patchCode(patched, inlineChunksRule);
+
+				return `${patched}\n${inlineChunksFn(tracedFiles)}`;
+			},
+		},
+	],
+};
+
+function getInlinableChunks(tracedFiles: string[]): string[] {
+	const chunks = new Set<string>();
+	for (const file of tracedFiles) {
+		if (file === "[turbopack]_runtime.js") {
+			continue;
+		}
+		if (file.includes(".next/server/chunks/")) {
+			chunks.add(file);
+		}
+	}
+	return Array.from(chunks);
+}
+
+function inlineChunksFn(tracedFiles: string[]) {
+	// From the outputs, we extract every chunks
+	const chunks = getInlinableChunks(tracedFiles);
+	return `
+  function requireChunk(chunkPath) {
+    switch(chunkPath) {
+${chunks
+	.map(
+		(chunk) =>
+			`      case "${
+				// we only want the path after /path/to/.next/
+				chunk.replace(/.*\/\.next\//, "")
+			}": return require("${chunk}");`
+	)
+	.join("\n")}
+      default:
+        throw new Error(\`Not found \${chunkPath}\`);
+    }
+  }
+`;
+}
+
+// Turbopack imports `og` via `externalImport`.
+// We patch it to:
+// - add the explicit path so that the file is inlined by wrangler
+// - use the edge version of the module instead of the node version.
+//
+// Modules that are not inlined (no added to the switch), would generate an error similar to:
+// Failed to load external module path/to/module: Error: No such module "path/to/module"
+const inlineExternalImportRule = `
+rule:
+  pattern: "$RAW = await import($ID)"
+  inside:
+    regex: "externalImport"
+    kind: function_declaration
+    stopBy: end
+fix: |-
+  switch ($ID) {
+    case "next/dist/compiled/@vercel/og/index.node.js":
+      $RAW = await import("next/dist/compiled/@vercel/og/index.edge.js");
+      break;
+    default:
+      $RAW = await import($ID);
+  }
+`;