Powertools MCP Search Server

import { HttpResponse, http } from 'msw'; import { setupServer } from 'msw/node'; import { afterAll, afterEach, beforeAll, describe, expect, it, vi, } from 'vitest'; import { CACHE_BASE_PATH, POWERTOOLS_BASE_URL } from '../../src/constants.ts'; import { schema, tool } from '../../src/tools/fetchDocPage/index.ts'; const mocks = vi.hoisted(() => ({ getFromCache: vi.fn(), writeToCache: vi.fn(), })); vi.mock('cacache', async (importOriginal) => ({ ...(await importOriginal<typeof import('cacache')>()), get: mocks.getFromCache, put: mocks.writeToCache, })); describe('schema', () => { it.each([ { type: 'latest', url: `${POWERTOOLS_BASE_URL}/typescript/latest/features/metrics/`, }, { type: 'semver', url: `${POWERTOOLS_BASE_URL}/typescript/1.2.4/features/metrics/`, }, { type: 'dotnet no version', url: `${POWERTOOLS_BASE_URL}/dotnet/features/metrics/`, }, ])('parses a valid URL ($type)', ({ url }) => { // Act const result = schema.url.parse(url); // Assess expect(result).toEqual(new URL(`${url}index.md`)); }); it('handles an URL without a trailing slash', () => { // Prepare const url = `${POWERTOOLS_BASE_URL}/typescript/latest/features/metrics`; // Act const result = schema.url.parse(url); // Assess expect(result).toEqual(new URL(`${url}/index.md`)); }); it('rejects an invalid URL', () => { // Prepare const url = 'https://foo'; // Act & Assess expect(() => schema.url.parse(url)).toThrow(); }); it('rejects an URL not allow-listed', () => { // Prepare const url = 'https://foo.com/typescript/latest/features/metrics/'; // Act & Assess expect(() => schema.url.parse(url)).toThrow(); }); it('rejects an URL with an invalid runtime', () => { // Prepare const url = `${POWERTOOLS_BASE_URL}/invalid-runtime/latest/features/metrics/`; // Act & Assess expect(() => schema.url.parse(url)).toThrow(); }); it('rejects an URL with an invalid version', () => { // Prepare const invalidUrl = `${POWERTOOLS_BASE_URL}/typescript/invalid-version/features/metrics/`; // Act & Assess expect(() => schema.url.parse(invalidUrl)).toThrow(); }); }); describe('tool', () => { const baseUrl = `${POWERTOOLS_BASE_URL}/typescript/latest/features/`; const server = setupServer( ...[ http.get( `${POWERTOOLS_BASE_URL}/typescript/latest/features/metrics/index.md`, () => HttpResponse.text( 'Metrics is a feature of PowerTools for TypeScript.', { headers: { 'Content-Type': 'text/markdown', ETag: '"12345"', }, } ) ), http.get( `${POWERTOOLS_BASE_URL}/typescript/latest/features/non-existent`, () => HttpResponse.json({ error: 'Not found' }, { status: 404 }) ), ] ); beforeAll(() => server.listen()); afterEach(() => { server.resetHandlers(); vi.clearAllMocks(); }); afterAll(() => server.close()); it('fetches a documentation page', async () => { // Prepare mocks.getFromCache.mockRejectedValueOnce(new Error('Cache miss')); const url = new URL(`${baseUrl}metrics/index.md`); const cacheKey = url.pathname; // Act const result = await tool({ url }); // Assess expect(result.content).toBeResponseWithText( 'Metrics is a feature of PowerTools for TypeScript.' ); expect(mocks.getFromCache).toHaveBeenCalledExactlyOnceWith( expect.stringContaining(CACHE_BASE_PATH), `${cacheKey}-etag` ); }); it('gracefully handles errors when fetching remote page', async () => { // Prepare mocks.getFromCache.mockResolvedValueOnce(null); const url = new URL(`${baseUrl}non-existent`); // Act const result = await tool({ url }); // Assess expect(result.content).toBeResponseWithText( 'Failed to fetch remote resource' ); expect(result.isError).toBe(true); expect(mocks.writeToCache).not.toHaveBeenCalled(); }); });