Add Miniflare#getCaches method for accessing caches outside worker

Author: mrbbot

package.json

@@ -58,6 +58,6 @@
     "node": ">=16.7"
   },
   "volta": {
-    "node": "16.9.0"
+    "node": "16.13.0"
   }
 }

packages/cache/src/plugin.ts

@@ -121,18 +121,24 @@ export class CachePlugin extends Plugin<CacheOptions> implements CacheOptions {
   })
   cacheWarnUsage?: boolean;
 
+  #caches?: CacheStorage;
+
   constructor(log: Log, compat: Compatibility, options?: CacheOptions) {
     super(log, compat);
     this.assignOptions(options);
   }
 
   setup(storageFactory: StorageFactory): SetupResult {
-    const caches = new CacheStorage(
+    this.#caches = new CacheStorage(
       this,
       this.log,
       storageFactory,
       this.compat.isEnabled("formdata_parser_supports_files")
     );
-    return { globals: { caches } };
+    return { globals: { caches: this.#caches } };
+  }
+
+  getCaches(): CacheStorage {
+    return this.#caches!;
   }
 }

packages/cache/test/plugin.spec.ts

@@ -146,6 +146,7 @@ test("CachePlugin: setup: includes CacheStorage in globals", async (t) => {
   let caches = result.globals?.caches;
   t.true(caches instanceof CacheStorage);
   assert(caches instanceof CacheStorage);
+  t.is(caches, plugin.getCaches());
   await caches.default.put("http://localhost:8787/", testResponse());
   t.true(map.has("http://localhost:8787/"));
 

packages/miniflare/src/api.ts

@@ -1,6 +1,6 @@
 import http from "http";
 import https from "https";
-import { CachePlugin } from "@miniflare/cache";
+import { CachePlugin, CacheStorage } from "@miniflare/cache";
 import {
   BindingsPlugin,
   BuildPlugin,
@@ -93,6 +93,11 @@ export class Miniflare extends MiniflareCore<Plugins> {
     return plugin.getNamespace(storage, namespace);
   }
 
+  async getCaches(): Promise<CacheStorage> {
+    const plugin = (await this.getPlugins()).CachePlugin;
+    return plugin.getCaches();
+  }
+
   async getDurableObjectNamespace(
     objectName: string
   ): Promise<DurableObjectNamespace> {

packages/miniflare/test/api.spec.ts

@@ -65,6 +65,12 @@ test("Miniflare: getKVNamespace: gets KV namespace", async (t) => {
   const res = await mf.dispatchFetch("http://localhost/");
   t.is(await res.text(), "value");
 });
+test("Miniflare: getCaches: gets CacheStorage instance", async (t) => {
+  const mf = new Miniflare({ script: "//" });
+  const caches = await mf.getCaches();
+  const globalScope = await mf.getGlobalScope();
+  t.is(caches, globalScope.caches);
+});
 test("Miniflare: getDurableObjectNamespace: gets Durable Object namespace", async (t) => {
   const mf = new Miniflare({
     script: `export class TestObject {