add cf binding support

packages/adapter-cloudflare/ambient.d.ts

@@ -3,11 +3,11 @@ import { Cache, CacheStorage, IncomingRequestCfProperties } from '@cloudflare/wo
 declare global {
 	namespace App {
 		export interface Platform {
-			context?: {
+			context: {
 				waitUntil(promise: Promise<any>): void;
 			};
-			caches?: CacheStorage & { default: Cache };
-			cf?: IncomingRequestCfProperties;
+			caches: CacheStorage;
+			cf: IncomingRequestCfProperties;
 		}
 	}
 }

packages/adapter-cloudflare/index.d.ts

@@ -42,6 +42,32 @@ export interface AdapterOptions {
 		 */
 		exclude?: string[];
 	};
+
+	/**
+	 * What bindings will be emulated in local development. This does not sync with your setup
+	 * on the Cloudflare Dashboard automatically.
+	 */
+	bindings?: {
+		kvNamespaces?: string[] | Record<string, string>;
+		r2Buckets?: string[] | Record<string, string>;
+		d1Databases?: string[] | Record<string, string>;
+		/**
+		 * Durable Object Bindings. Separate Worker required for Durable Object definition.
+		 */
+		durableObjects: Record<
+			string,
+			{
+				className: string;
+				scriptName: string;
+			}
+		>;
+		vars?: Record<string, string>;
+	};
+
+	/**
+	 * Where to persist Cloudflare-related data. Defaults to `.wrangler`
+	 */
+	persistTo?: string;
 }
 
 export interface RoutesJSONSpec {

packages/adapter-cloudflare/index.js

@@ -2,6 +2,7 @@ import { writeFileSync } from 'node:fs';
 import * as path from 'node:path';
 import { fileURLToPath } from 'node:url';
 import * as esbuild from 'esbuild';
+import { Miniflare } from 'miniflare';
 
 // list from https://developers.cloudflare.com/workers/runtime-apis/nodejs/
 const compatible_node_modules = [
@@ -20,6 +21,19 @@ const compatible_node_modules = [
 
 /** @type {import('./index.js').default} */
 export default function (options = {}) {
+	const persistTo = options.persistTo || '.wrangler';
+	const mf = new Miniflare({
+		script: 'export default{fetch({cf:e}){return Response.json(e)}}',
+		modules: true,
+		kvNamespaces: options.bindings?.kvNamespaces,
+		kvPersist: persistTo,
+		r2Buckets: options.bindings?.r2Buckets,
+		r2Persist: persistTo,
+		durableObjects: options.bindings?.durableObjects,
+		durableObjectsPersist: persistTo,
+		bindings: options.bindings?.vars,
+		cachePersist: persistTo
+	});
 	return {
 		name: '@sveltejs/adapter-cloudflare',
 		async adapt(builder) {
@@ -124,6 +138,23 @@ export default function (options = {}) {
 					}`
 				);
 			}
+		},
+		async emulate() {
+			/** @type {import('@cloudflare/workers-types').CacheStorage} */
+			const caches = /** @type {any} */ (await mf.getCaches());
+			/** @type {import('@cloudflare/workers-types').IncomingRequestCfProperties} */
+			const cf = /** @type {any} */ (await (await mf.dispatchFetch('http://svelte.kit')).json());
+			const env = await mf.getBindings();
+			return {
+				platform: () => ({
+					context: {
+						waitUntil: (prom) => prom
+					},
+					caches,
+					cf,
+					env
+				})
+			};
 		}
 	};
 }

packages/adapter-cloudflare/package.json

@@ -34,7 +34,8 @@
 	"dependencies": {
 		"@cloudflare/workers-types": "^4.20231121.0",
 		"esbuild": "^0.19.11",
-		"worktop": "0.8.0-next.18"
+		"worktop": "0.8.0-next.18",
+		"miniflare": "^3.20240129.0"
 	},
 	"devDependencies": {
 		"@sveltejs/kit": "workspace:^",