Add MSW plugin for API mocking in testing and development

[Copilot]

Implements Mock Service Worker integration for ObjectStack, enabling browser and Node.js API mocking without server infrastructure.

Implementation

New Package: @objectstack/plugin-msw

• MSWPlugin - Runtime plugin implementing automatic handler generation for all ObjectStack endpoints
• ObjectStackServer - Simplified mock API for common CRUD operations
• Auto-generates handlers for discovery, metadata, data, and UI protocol endpoints

Example Package: @objectstack/example-msw-demo

• Browser standalone usage pattern
• Runtime integration pattern

Usage

Browser Mode (standalone):

import { setupWorker } from 'msw/browser';
import { http, HttpResponse } from 'msw';
import { ObjectStackServer } from '@objectstack/plugin-msw';

ObjectStackServer.init(protocol);

const handlers = [
  http.get('/api/user/:id', async ({ params }) => {
    const result = await ObjectStackServer.getUser(params.id);
    return HttpResponse.json(result.data, { status: result.status });
  })
];

export const worker = setupWorker(...handlers);

Runtime Integration:

const kernel = new ObjectStackKernel([
  new MSWPlugin({ baseUrl: '/api/v1', logRequests: true })
]);

Endpoints Mocked

• /api/v1 - Discovery
• /api/v1/meta[/:type[/:name]] - Metadata access
• /api/v1/data/:object[/:id] - CRUD operations (GET, POST, PATCH, DELETE)
• /api/v1/ui/view/:object - UI protocol

Original prompt

新增插件，支持 msn

// mocks/browser.js
import { setupWorker, rest } from 'msw';
import { ObjectStackServer } from '../server/mock-db';

// 1. 初始化模拟服务端
ObjectStackServer.init();

// 2. 定义路由处理器 (Handlers)
// 这就像是 Express/Koa 的路由定义，但运行在 Service Worker 中
const handlers = [

// 拦截 GET /api/user/:id
rest.get('/api/user/:id', async (req, res, ctx) => {
const { id } = req.params;

// 调用本地逻辑
const result = await ObjectStackServer.getUser(id);

// 返回构建的 Response
return res(
  ctx.status(result.status),
  ctx.json(result.data)
);

}),

// 拦截 POST /api/user
rest.post('/api/user', async (req, res, ctx) => {
const body = await req.json();

// 调用本地逻辑
const result = await ObjectStackServer.createUser(body);

return res(
  ctx.status(result.status),
  ctx.json(result.data)
);

}),
];

// 3. 创建 Worker 实例
export const worker = setupWorker(...handlers);

---

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Project	Deployment	Review	Updated (UTC)
spec	Error		Jan 24, 2026 3:50am

[Copilot]

Pull request overview

This PR adds Mock Service Worker (MSW) integration to ObjectStack, enabling browser and Node.js API mocking without server infrastructure. The implementation includes a new plugin package and example usage demonstrations.

Changes:

• New @objectstack/plugin-msw package with MSWPlugin and ObjectStackServer classes for automatic MSW handler generation
• Example package @objectstack/example-msw-demo demonstrating both browser standalone and runtime integration patterns
• Automatic endpoint generation for discovery, metadata, data CRUD operations, and UI protocol

Reviewed changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
packages/plugin-msw/package.json	Package configuration with MSW 2.0+ dependency and runtime peer dependency
packages/plugin-msw/src/msw-plugin.ts	Main plugin implementing RuntimePlugin interface with handler generation logic
packages/plugin-msw/src/index.ts	Package exports for MSWPlugin, ObjectStackServer, and MSW types
packages/plugin-msw/tsconfig.json	TypeScript configuration for ES2020 modules
packages/plugin-msw/README.md	Comprehensive documentation with usage examples and API reference
packages/plugin-msw/CHANGELOG.md	Version 0.3.1 initial release notes
examples/msw-demo/package.json	Example package dependencies and scripts
examples/msw-demo/src/server.ts	Runtime integration pattern example
examples/msw-demo/src/browser.ts	Browser standalone usage example
examples/msw-demo/tsconfig.json	TypeScript configuration for NodeNext modules
examples/msw-demo/README.md	Example usage documentation
pnpm-lock.yaml	Lock file updates for new packages and MSW dependencies

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

[Copilot]

The onStop lifecycle method is not part of the RuntimePlugin interface. The interface only defines optional install and onStart methods (see packages/runtime/src/types.ts). This method will never be called by the kernel and represents dead code. Consider removing it or extending the RuntimePlugin interface to include an onStop hook if this functionality is needed.

Suggested change

	async onStop() {
	if (this.worker) {
	this.worker.stop();
	console.log(`[MSWPlugin] Stopped MSW worker.`);
	}
	}

[Copilot]

The mock protocol object uses TypeScript any type casting without proper error handling or type checking. This could lead to runtime errors if the protocol methods are not properly implemented. Consider creating a proper mock that implements the expected protocol interface or using a testing library to create type-safe mocks.

Suggested change

	const mockProtocol = {
	getData: async (object: string, id: string) => {
	return { id, object, name: `Mock ${object}`, status: 'active' };
	},
	createData: async (object: string, data: any) => {
	return { id: 'new-id', ...data };
	},
	// Add other methods as needed
	} as any;
	interface MockProtocol {
	getData(object: string, id: string): Promise<unknown>;
	createData(object: string, data: unknown): Promise<unknown>;
	}
	const mockProtocol: MockProtocol = {
	getData: async (object: string, id: string) => {
	return { id, object, name: `Mock ${object}`, status: 'active' };
	},
	createData: async (object: string, data: unknown) => {
	return { id: 'new-id', ...data as Record<string, unknown> };
	},
	// Add other methods as needed
	};

[Copilot]

Using Array<any> for handler types weakens type safety. MSW provides specific handler types (e.g., RequestHandler from 'msw') that should be used instead. This would provide better type checking and IDE support for consumers of this API.

[Copilot]

Using Array<any> for the handlers property weakens type safety. Consider using a more specific type like RequestHandler[] from MSW to provide better type checking.

[Copilot]

Using any type for the worker weakens type safety. Consider importing and using the proper type from MSW (e.g., SetupWorker from 'msw/browser') to provide better type checking and IDE support.

Suggested change

	private worker: any;
	private worker: ReturnType<typeof setupWorker> | null = null;

[Copilot]

The error handling pattern here catches errors and returns a 404 status, but the getData method in ObjectStackServer.getData already handles errors and returns a response object with status and data. This creates a double error handling that could mask the original error. The outer try-catch may be unnecessary since ObjectStackServer.getData already handles errors internally.

Suggested change

	try {
	const result = await ObjectStackServer.getData(
	params.object as string,
	params.id as string
	);
	return HttpResponse.json(result.data, { status: result.status });
	} catch (error) {
	const message = error instanceof Error ? error.message : 'Unknown error';
	return HttpResponse.json({ error: message }, { status: 404 });
	}
	const result = await ObjectStackServer.getData(
	params.object as string,
	params.id as string
	);
	return HttpResponse.json(result.data, { status: result.status });

[Copilot]

The plugin name 'msw' is inconsistent with the naming pattern used in other ObjectStack plugins. For example, HonoServerPlugin uses 'com.objectstack.server.hono' (reverse domain notation). Consider using a similar pattern like 'com.objectstack.msw' or 'com.objectstack.plugin.msw' for consistency across the codebase.