Implement KV storage endpoints for Local Explorer API

Add REST API endpoints for KV storage operations:
- GET /storage/kv/namespaces - List namespaces
- GET /storage/kv/namespaces/:id/keys - List keys
- GET /storage/kv/namespaces/:id/values/:key - Get value
- PUT /storage/kv/namespaces/:id/values/:key - Write value
- DELETE /storage/kv/namespaces/:id/values/:key - Delete key
- POST /storage/kv/namespaces/:id/bulk/get - Bulk get values

Author: emily-shen

fixtures/worker-with-resources/wrangler.jsonc

@@ -7,6 +7,10 @@
 		{
 			"binding": "KV",
 		},
+		{
+			"binding": "KV_WITH_ID",
+			"id": "some-kv-id",
+		},
 	],
 	"d1_databases": [
 		{

packages/miniflare/src/workers/local-explorer/api.worker.ts

@@ -1,10 +1,47 @@
 // local explorer API Worker
 // Provides a REST API for viewing and manipulating user resources
 
-import { WorkerEntrypoint } from "cloudflare:workers";
+import { fromHono } from "chanfana";
+import { Hono } from "hono";
+import {
+	BulkGetKVValues,
+	DeleteKVValue,
+	GetKVValue,
+	ListKVKeys,
+	ListKVNamespaces,
+	PutKVValue,
+} from "./resources/kv";
+import type { AppBindings } from "./common";
 
-export default class LocalExplorerAPI extends WorkerEntrypoint {
-	async fetch(): Promise<Response> {
-		return new Response("Hello from local explorer API");
-	}
-}
+const BASE_PATH = "/cdn-cgi/explorer/api";
+
+const app = new Hono<AppBindings>().basePath(BASE_PATH);
+
+const openapi = fromHono(app, {
+	docs_url: "/docs",
+	schema: {
+		openapi: "3.0.0",
+		info: {
+			title: "Local Explorer API",
+			version: "1.0.0",
+			description:
+				"A local subset of Cloudflare's REST API for exploring resources during local development.",
+		},
+	},
+});
+
+// ============================================================================
+// KV Endpoints
+// ============================================================================
+
+openapi.get("/storage/kv/namespaces", ListKVNamespaces);
+openapi.get("/storage/kv/namespaces/:namespaceId/keys", ListKVKeys);
+openapi.get("/storage/kv/namespaces/:namespaceId/values/:keyName", GetKVValue);
+openapi.put("/storage/kv/namespaces/:namespaceId/values/:keyName", PutKVValue);
+openapi.delete(
+	"/storage/kv/namespaces/:namespaceId/values/:keyName",
+	DeleteKVValue
+);
+openapi.post("/storage/kv/namespaces/:namespaceId/bulk/get", BulkGetKVValues);
+
+export default app;

packages/miniflare/src/workers/local-explorer/common.ts

@@ -0,0 +1,74 @@
+import { z } from "zod";
+
+// ============================================================================
+// Zod Schemas (for OpenAPI docs and runtime validation)
+// ============================================================================
+//
+// NOTE: Do not use z.coerce for query/path parameters. The chanfana library
+// automatically handles string-to-number coercion for these parameters.
+// Using z.coerce is redundant and unnecessary.
+
+export const ResponseInfoSchema = z.object({
+	code: z.number(),
+	message: z.string(),
+});
+
+// Page-based pagination schema (for namespace listing)
+export const PageResultInfoSchema = z.object({
+	count: z.number(),
+	page: z.number(),
+	per_page: z.number(),
+	total_count: z.number(),
+});
+
+// Cursor-based pagination schema (for key listing)
+export const CursorResultInfoSchema = z.object({
+	count: z.number(),
+	cursor: z.string(),
+});
+
+// Helper to create envelope schema for OpenAPI docs
+export const CloudflareEnvelope = <T extends z.ZodTypeAny>(resultSchema: T) =>
+	z.object({
+		success: z.boolean(),
+		errors: z.array(ResponseInfoSchema),
+		messages: z.array(ResponseInfoSchema),
+		result: resultSchema,
+	});
+
+// ============================================================================
+// Response Helpers
+// ============================================================================
+
+// Wrap result in Cloudflare envelope
+export function wrapResponse<T>(result: T) {
+	return {
+		success: true as const,
+		errors: [] as { code: number; message: string }[],
+		messages: [] as { code: number; message: string }[],
+		result,
+	};
+}
+
+// Create error response
+export function errorResponse(status: number, code: number, message: string) {
+	return Response.json(
+		{
+			success: false,
+			errors: [{ code, message }],
+			messages: [],
+			result: null,
+		},
+		{ status }
+	);
+}
+
+// ============================================================================
+// Shared Types
+// ============================================================================
+
+export interface Env {
+	[key: string]: unknown;
+}
+
+export type AppBindings = { Bindings: Env };