add support for assets bindings to getPlatformProxy

Author: dario-piotrowicz

.changeset/thick-dots-sit.md

@@ -0,0 +1,39 @@
+---
+"wrangler": patch
+---
+
+add support for assets bindings to `getPlatformProxy`
+
+this change makes sure that that `getPlatformProxy`, when the input configuration
+file contains an assets field, correctly returns the appropriate asset binding proxy
+
+example:
+
+```json
+// wrangler.json
+{
+	"name": "my-worker",
+	"assets": {
+		"directory": "./public/",
+		"binding": "ASSETS"
+	},
+	"vars": {
+		"MY_VAR": "my-var"
+	}
+}
+```
+
+```js
+import { getPlatformProxy } from "wrangler";
+
+const { env } = await getPlatformProxy();
+
+if (env.ASSETS) {
+	const text = await (
+		await p.env.ASSETS.fetch("http://0.0.0.0/file.txt")
+	).text();
+	console.log(text); // logs the content of file.txt
+}
+
+p.dispose();
+```

fixtures/get-platform-proxy/public/test.txt

@@ -0,0 +1 @@
+this is a test text file!

fixtures/get-platform-proxy/tests/get-platform-proxy.env.test.ts

@@ -2,7 +2,11 @@ import path from "path";
 import { D1Database, R2Bucket } from "@cloudflare/workers-types";
 import { beforeEach, describe, expect, it, vi } from "vitest";
 import { getPlatformProxy } from "./shared";
-import type { Hyperdrive, KVNamespace } from "@cloudflare/workers-types";
+import type {
+	Fetcher,
+	Hyperdrive,
+	KVNamespace,
+} from "@cloudflare/workers-types";
 import type { Unstable_DevWorker } from "wrangler";
 
 type Env = {
@@ -15,6 +19,7 @@ type Env = {
 	MY_BUCKET: R2Bucket;
 	MY_D1: D1Database;
 	MY_HYPERDRIVE: Hyperdrive;
+	ASSETS: Fetcher;
 };
 
 const wranglerTomlFilePath = path.join(__dirname, "..", "wrangler.toml");
@@ -115,6 +120,17 @@ describe("getPlatformProxy - env", () => {
 		}
 	});
 
+	it("correctly obtains functioning ASSETS bindings", async () => {
+		const { env, dispose } = await getPlatformProxy<Env>({
+			configPath: wranglerTomlFilePath,
+		});
+		const { ASSETS } = env;
+		const res = await ASSETS.fetch("https://0.0.0.0/test.txt");
+		const text = await res.text();
+		expect(text).toEqual("this is a test text file!\n");
+		await dispose();
+	});
+
 	it("correctly obtains functioning KV bindings", async () => {
 		const { env, dispose } = await getPlatformProxy<Env>({
 			configPath: wranglerTomlFilePath,

fixtures/get-platform-proxy/wrangler.toml

@@ -7,6 +7,12 @@ MY_VAR = "my-var-value"
 MY_VAR_A = "my-var-a"
 MY_JSON_VAR = { test = true }
 
+[assets]
+directory = "./public"
+binding = "ASSETS"
+html_handling = "auto-trailing-slash"
+not_found_handling = "none"
+
 [[kv_namespaces]]
 binding = "MY_KV"
 id = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"

packages/wrangler/src/api/integrations/platform/index.ts

@@ -1,5 +1,6 @@
 import { kCurrentWorker, Miniflare } from "miniflare";
-import { getAssetsOptions } from "../../../assets";
+import type { AssetsOptions} from "../../../assets";
+import { getAssetsOptions, NonExistentAssetsDirError } from "../../../assets";
 import { readConfig } from "../../../config";
 import { DEFAULT_MODULE_RULES } from "../../../deployment-bundle/rules";
 import { getBindings } from "../../../dev";
@@ -159,6 +160,28 @@ async function getMiniflareOptionsFromConfig(
 		imagesLocalMode: false,
 	});
 
+
+	let processedAssetOptions: AssetsOptions|undefined;
+
+	try {
+		processedAssetOptions = getAssetsOptions(
+			{ assets: undefined },
+			rawConfig,
+		);
+	} catch (e) {
+		const isNonExistentError = e instanceof NonExistentAssetsDirError;
+		// we want to loosen up the assets directory existence restriction here,
+		// since `getPlatformProxy` can be run when the assets directory doesn't actual
+		// exist (yes), but all other exceptions should still be thrown
+		if(!isNonExistentError) {
+			throw e;
+		}
+	}
+
+	const assetOptions = processedAssetOptions
+		? buildAssetOptions({ assets: processedAssetOptions })
+		: {};
+
 	const persistOptions = getMiniflarePersistOptions(options.persist);
 
 	const serviceBindings = await getServiceBindings(bindings.services);
@@ -173,6 +196,7 @@ async function getMiniflareOptionsFromConfig(
 					...serviceBindings,
 					...bindingOptions.serviceBindings,
 				},
+				...assetOptions,
 			},
 			...externalWorkers,
 		],

packages/wrangler/src/assets.ts

@@ -321,6 +321,9 @@ export type AssetsOptions = {
 	assetConfig: AssetConfig;
 };
 
+
+export class NonExistentAssetsDirError extends UserError {}
+
 export function getAssetsOptions(
 	args: { assets: string | undefined; script?: string },
 	config: Config
@@ -351,9 +354,9 @@ export function getAssetsOptions(
 			? '"--assets" command line argument'
 			: '"assets.directory" field in your configuration file';
 
-		throw new UserError(
+		throw new nonExistentAssetsDirError(
 			`The directory specified by the ${sourceOfTruthMessage} does not exist:\n` +
-				`${resolvedAssetsPath}`
+				`${resolvedAssetsPath}`,
 		);
 	}