fix: resolve raw file bindings correctly in wrangler dev local mode (#756)

For `wasm_modules`/`text_blobs`/`data_blobs` in local mode, we need to rewrite the paths as absolute so that they're resolved correctly by miniflare. This also expands some coverage for local mode `wrangler dev`.

Fixes #740
Fixes #416

Author: threepointone

.changeset/flat-ads-flash.md

@@ -0,0 +1,10 @@
+---
+"wrangler": patch
+---
+
+fix: resolve raw file bindings correctly in `wrangler dev` local mode
+
+For `wasm_modules`/`text_blobs`/`data_blobs` in local mode, we need to rewrite the paths as absolute so that they're resolved correctly by miniflare. This also expands some coverage for local mode `wrangler dev`.
+
+Fixes https://github.com/cloudflare/wrangler2/issues/740
+Fixes https://github.com/cloudflare/wrangler2/issues/416

examples/local-mode-tests/package.json

@@ -5,8 +5,12 @@
   "description": "",
   "main": "index.js",
   "scripts": {
+    "check:type": "tsc",
     "test": "npx jest --forceExit"
   },
+  "devDependencies": {
+    "@cloudflare/workers-types": "^3.2.0"
+  },
   "keywords": [],
   "author": "",
   "license": "ISC",

examples/local-mode-tests/some-data.bin

@@ -0,0 +1 @@
+Here be some data

examples/local-mode-tests/some-text.txt

@@ -0,0 +1 @@
+Here be some text

examples/local-mode-tests/src/index.ts

@@ -0,0 +1,23 @@
+// @ts-expect-error non standard module
+import data from "../some-data.bin";
+// @ts-expect-error non standard module
+import text from "../some-text.txt";
+
+export default {
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  async fetch(_request: Request, env: any): Promise<Response> {
+    return new Response(
+      JSON.stringify(
+        {
+          VAR1: env.VAR1,
+          VAR2: env.VAR2,
+          VAR3: env.VAR3,
+          text,
+          data: new TextDecoder().decode(data),
+        },
+        null,
+        2
+      )
+    );
+  },
+};

examples/local-mode-tests/src/module.ts

@@ -0,0 +1,31 @@
+// @ts-expect-error non standard module
+import data from "../some-data.bin";
+// @ts-expect-error non standard module
+import text from "../some-text.txt";
+
+addEventListener("fetch", (event: FetchEvent) => {
+  event.respondWith(handleRequest(event.request));
+});
+
+async function handleRequest(_req: Request): Promise<Response> {
+  return new Response(
+    JSON.stringify(
+      {
+        // @ts-expect-error binding
+        VAR1,
+        // @ts-expect-error binding
+        VAR2,
+        // @ts-expect-error binding
+        VAR3,
+        text,
+        data: new TextDecoder().decode(data),
+        // @ts-expect-error binding
+        TEXT,
+        // @ts-expect-error binding
+        DATA: new TextDecoder().decode(DATA),
+      },
+      null,
+      2
+    )
+  );
+}

examples/local-mode-tests/src/sw.ts

@@ -1,3 +1,7 @@
 name = "local-mode-tests"
-main = "src/index.ts"
 compatibility_date = "2022-03-27"
+
+[vars]
+VAR1 = "value1"
+VAR2 = 123
+VAR3 = {abc = "def"}

examples/local-mode-tests/wrangler.toml renamed to examples/local-mode-tests/src/wrangler.module.toml

@@ -0,0 +1,13 @@
+name = "local-mode-tests"
+compatibility_date = "2022-03-27"
+
+[vars]
+VAR1 = "value1"
+VAR2 = 123
+VAR3 = {abc = "def"}
+
+[text_blobs]
+TEXT = "../some-text.txt"
+
+[data_blobs]
+DATA = "../some-data.bin"

examples/local-mode-tests/src/wrangler.sw.toml

@@ -21,9 +21,23 @@ const isWindows = process.platform === "win32";
 let wranglerProcess: ChildProcess;
 
 beforeAll(async () => {
-  wranglerProcess = spawn("npx", ["wrangler", "dev", "--local"], {
-    shell: isWindows,
-  });
+  wranglerProcess = spawn(
+    "npx",
+    [
+      "wrangler",
+      "dev",
+      "src/module.ts",
+      "--local",
+      "--config",
+      "src/wrangler.module.toml",
+      "--port",
+      "9001",
+    ],
+    {
+      shell: isWindows,
+      stdio: "inherit",
+    }
+  );
 });
 
 afterAll(async () => {
@@ -40,7 +54,17 @@ afterAll(async () => {
 });
 
 it("renders", async () => {
-  const response = await waitUntilReady("http://localhost:8787/");
+  const response = await waitUntilReady("http://localhost:9001/");
   const text = await response.text();
-  expect(text).toContain("Hello World!");
+  expect(text).toMatchInlineSnapshot(`
+    "{
+      \\"VAR1\\": \\"value1\\",
+      \\"VAR2\\": 123,
+      \\"VAR3\\": {
+        \\"abc\\": \\"def\\"
+      },
+      \\"text\\": \\"Here be some text\\",
+      \\"data\\": \\"Here be some data\\"
+    }"
+  `);
 });

examples/local-mode-tests/tests/index.test.ts renamed to examples/local-mode-tests/tests/module.test.ts

@@ -0,0 +1,72 @@
+import { spawn } from "child_process";
+import { fetch } from "undici";
+import type { ChildProcess } from "child_process";
+import type { Response } from "undici";
+
+const waitUntilReady = async (url: string): Promise<Response> => {
+  let response: Response | undefined = undefined;
+
+  while (response === undefined) {
+    await new Promise((resolvePromise) => setTimeout(resolvePromise, 100));
+
+    try {
+      response = await fetch(url);
+    } catch {}
+  }
+
+  return response as Response;
+};
+const isWindows = process.platform === "win32";
+
+let wranglerProcess: ChildProcess;
+
+beforeAll(async () => {
+  wranglerProcess = spawn(
+    "npx",
+    [
+      "wrangler",
+      "dev",
+      "src/sw.ts",
+      "--local",
+      "--config",
+      "src/wrangler.sw.toml",
+      "--port",
+      "9002",
+    ],
+    {
+      shell: isWindows,
+      stdio: "inherit",
+    }
+  );
+});
+
+afterAll(async () => {
+  await new Promise((resolve, reject) => {
+    wranglerProcess.once("exit", (code) => {
+      if (!code) {
+        resolve(code);
+      } else {
+        reject(code);
+      }
+    });
+    wranglerProcess.kill();
+  });
+});
+
+it("renders", async () => {
+  const response = await waitUntilReady("http://localhost:9002/");
+  const text = await response.text();
+  expect(text).toMatchInlineSnapshot(`
+    "{
+      \\"VAR1\\": \\"value1\\",
+      \\"VAR2\\": 123,
+      \\"VAR3\\": {
+        \\"abc\\": \\"def\\"
+      },
+      \\"text\\": \\"Here be some text\\",
+      \\"data\\": \\"Here be some data\\",
+      \\"TEXT\\": \\"Here be some text\\",
+      \\"DATA\\": \\"Here be some data\\"
+    }"
+  `);
+});

examples/local-mode-tests/tests/sw.test.ts

@@ -9,6 +9,7 @@
     "target": "esnext",
     "strict": true,
     "noEmit": true,
+    "types": ["@cloudflare/workers-types", "jest"],
     "skipLibCheck": true
   }
 }

examples/local-mode-tests/tsconfig.json

@@ -83,9 +83,35 @@ function useLocalWorker({
 
       const scriptPath = realpathSync(bundle.path);
 
-      const wasmBindings = { ...bindings.wasm_modules };
-      const textBlobBindings = { ...bindings.text_blobs };
-      const dataBlobBindings = { ...bindings.data_blobs };
+      // the wasm_modules/text_blobs/data_blobs bindings are
+      // relative to process.cwd(), but the actual worker bundle
+      // is in the temp output directory; so we rewrite the paths to be absolute,
+      // letting miniflare resolve them correctly
+
+      // wasm
+      const wasmBindings: Record<string, string> = {};
+      for (const [name, filePath] of Object.entries(
+        bindings.wasm_modules || {}
+      )) {
+        wasmBindings[name] = path.join(process.cwd(), filePath);
+      }
+
+      // text
+      const textBlobBindings: Record<string, string> = {};
+      for (const [name, filePath] of Object.entries(
+        bindings.text_blobs || {}
+      )) {
+        textBlobBindings[name] = path.join(process.cwd(), filePath);
+      }
+
+      // data
+      const dataBlobBindings: Record<string, string> = {};
+      for (const [name, filePath] of Object.entries(
+        bindings.data_blobs || {}
+      )) {
+        dataBlobBindings[name] = path.join(process.cwd(), filePath);
+      }
+
       if (format === "service-worker") {
         for (const { type, name } of bundle.modules) {
           if (type === "compiled-wasm") {
@@ -187,7 +213,7 @@ function useLocalWorker({
       });
 
       local.current.stdout?.on("data", (data: Buffer) => {
-        console.log(`${data.toString()}`);
+        process.stdout.write(data);
       });
 
       local.current.stderr?.on("data", (data: Buffer) => {