allow __STATIC_CONTENT_MANIFEST to be imported from any module

Author: mrbbot

.changeset/hot-deers-return.md

@@ -0,0 +1,8 @@
+---
+"wrangler": patch
+---
+
+fix: allow `__STATIC_CONTENT_MANIFEST` module to be imported anywhere
+
+`__STATIC_CONTENT_MANIFEST` can now be imported in subdirectories when
+`--no-bundle` or `find_additional_modules` are enabled.

packages/wrangler/src/__tests__/deploy.test.ts

@@ -2199,8 +2199,10 @@ addEventListener('fetch', event => {});`
 
 		it("when using a module worker type, it should add an asset manifest module, and bind to a namespace", async () => {
 			const assets = [
-				{ filePath: "file-1.txt", content: "Content of file-1" },
-				{ filePath: "file-2.txt", content: "Content of file-2" },
+				// Using `.text` extension instead of `.txt` means files won't be
+				// treated as additional modules
+				{ filePath: "file-1.text", content: "Content of file-1" },
+				{ filePath: "file-2.text", content: "Content of file-2" },
 			];
 			const kvNamespace = {
 				title: "__test-name-workers_sites_assets",
@@ -2211,8 +2213,27 @@ addEventListener('fetch', event => {});`
 				site: {
 					bucket: "assets",
 				},
+				find_additional_modules: true,
+				rules: [{ type: "ESModule", globs: ["**/*.mjs"] }],
 			});
 			writeWorkerSource({ type: "esm" });
+			fs.mkdirSync("a/b/c", { recursive: true });
+			fs.writeFileSync(
+				"a/1.mjs",
+				'export { default } from "__STATIC_CONTENT_MANIFEST";'
+			);
+			fs.writeFileSync(
+				"a/b/2.mjs",
+				'export { default } from "__STATIC_CONTENT_MANIFEST";'
+			);
+			fs.writeFileSync(
+				"a/b/3.mjs",
+				'export { default } from "__STATIC_CONTENT_MANIFEST";'
+			);
+			fs.writeFileSync(
+				"a/b/c/4.mjs",
+				'export { default } from "__STATIC_CONTENT_MANIFEST";'
+			);
 			writeAssets(assets);
 			mockUploadWorkerRequest({
 				expectedBindings: [
@@ -2224,7 +2245,13 @@ addEventListener('fetch', event => {});`
 				],
 				expectedModules: {
 					__STATIC_CONTENT_MANIFEST:
-						'{"file-1.txt":"file-1.2ca234f380.txt","file-2.txt":"file-2.5938485188.txt"}',
+						'{"file-1.text":"file-1.2ca234f380.text","file-2.text":"file-2.5938485188.text"}',
+					"a/__STATIC_CONTENT_MANIFEST":
+						'export { default } from "../__STATIC_CONTENT_MANIFEST";',
+					"a/b/__STATIC_CONTENT_MANIFEST":
+						'export { default } from "../../__STATIC_CONTENT_MANIFEST";',
+					"a/b/c/__STATIC_CONTENT_MANIFEST":
+						'export { default } from "../../../__STATIC_CONTENT_MANIFEST";',
 				},
 			});
 			mockSubDomainRequest();
@@ -2235,10 +2262,15 @@ addEventListener('fetch', event => {});`
 			await runWrangler("deploy");
 
 			expect(std.info).toMatchInlineSnapshot(`
-			"Fetching list of already uploaded assets...
+			"Attaching additional modules:
+			- a/1.mjs (esm)
+			- a/b/2.mjs (esm)
+			- a/b/3.mjs (esm)
+			- a/b/c/4.mjs (esm)
+			Fetching list of already uploaded assets...
 			Building list of assets to upload...
-			 + file-1.2ca234f380.txt (uploading new version of file-1.txt)
-			 + file-2.5938485188.txt (uploading new version of file-2.txt)
+			 + file-1.2ca234f380.text (uploading new version of file-1.text)
+			 + file-2.5938485188.text (uploading new version of file-2.text)
 			Uploading 2 new assets...
 			Uploaded 100% [2 out of 2]"
 		`);

packages/wrangler/src/deployment-bundle/create-worker-upload-form.ts

@@ -1,4 +1,6 @@
+import assert from "node:assert";
 import { readFileSync } from "node:fs";
+import path from "node:path";
 import { FormData, File } from "undici";
 import { handleUnsafeCapnp } from "./capnp";
 import type {
@@ -294,6 +296,48 @@ export function createWorkerUploadForm(worker: CfWorkerInit): FormData {
 		);
 	}
 
+	const manifestModuleName = "__STATIC_CONTENT_MANIFEST";
+	const hasManifest = modules?.some(({ name }) => name === manifestModuleName);
+	if (hasManifest && main.type === "esm") {
+		assert(modules !== undefined);
+		// Each modules-format worker has a virtual file system for module
+		// resolution. For example, uploading modules with names `1.mjs`,
+		// `a/2.mjs` and `a/b/3.mjs`, creates virtual directories `a` and `a/b`.
+		// `1.mjs` is in the virtual root directory.
+		//
+		// The above code adds the `__STATIC_CONTENT_MANIFEST` module to the root
+		// directory. This means `import manifest from "__STATIC_CONTENT_MANIFEST"`
+		// will only work if the importing module is also in the root. If the
+		// importing module was `a/b/3.mjs` for example, the import would need to
+		// be `import manifest from "../../__STATIC_CONTENT_MANIFEST"`.
+		//
+		// When Wrangler bundles all user code, this isn't a problem, as code is
+		// only ever uploaded to the root. However, once `--no-bundle` or
+		// `find_additional_modules` is enabled, the user controls the directory
+		// structure.
+		//
+		// To fix this, if we've got a modules-format worker, we add stub modules
+		// in each subdirectory that re-export the manifest module from the root.
+		// This allows the manifest to be imported as `__STATIC_CONTENT_MANIFEST`
+		// in every directory, whilst avoiding duplication of the manifest.
+
+		// Collect unique subdirectories
+		const subDirs = new Set(
+			modules.map((module) => path.posix.dirname(module.name))
+		);
+		for (const subDir of subDirs) {
+			// Ignore `.` as it's not a subdirectory, and we don't want to
+			// register the manifest module in the root twice.
+			if (subDir === ".") continue;
+			const relativePath = path.posix.relative(subDir, manifestModuleName);
+			modules.push({
+				name: path.posix.join(subDir, manifestModuleName),
+				content: `export { default } from ${JSON.stringify(relativePath)};`,
+				type: "esm",
+			});
+		}
+	}
+
 	if (main.type === "commonjs") {
 		// This is a service-worker format worker.
 		for (const module of Object.values([...(modules || [])])) {