Genkit MCP

/** * Copyright 2024 Google LLC * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import * as http from 'http'; import { AddressInfo } from 'net'; export interface MockResponse { statusCode?: number; body?: any; headers?: http.OutgoingHttpHeaders; stream?: boolean; chunks?: any[]; // For streaming } export class FakeOpenAIServer { private server: http.Server; private port: number = 0; private responses: MockResponse[] = []; public requests: { headers: http.IncomingHttpHeaders; body: any }[] = []; private expectedApiKey?: string; constructor(expectedApiKey?: string) { this.expectedApiKey = expectedApiKey; this.server = http.createServer(async (req, res) => { let body = ''; req.on('data', (chunk) => { body += chunk.toString(); }); await new Promise<void>((resolve) => req.on('end', resolve)); const parsedBody = body ? JSON.parse(body) : {}; this.requests.push({ headers: req.headers, body: parsedBody }); if (this.expectedApiKey) { const authHeader = req.headers['authorization']; if (!authHeader || authHeader !== `Bearer ${this.expectedApiKey}`) { res.writeHead(401, { 'Content-Type': 'application/json' }); res.end( JSON.stringify({ error: { message: 'Incorrect API key provided', type: 'invalid_request_error', param: null, code: 'invalid_api_key', }, }) ); return; } } const response = this.responses.shift(); if (!response) { // Default response if nothing queued res.writeHead(200, { 'Content-Type': 'application/json' }); res.end( JSON.stringify({ choices: [ { message: { role: 'assistant', content: 'default response' }, finish_reason: 'stop', }, ], }) ); return; } const statusCode = response.statusCode || 200; const headers = response.headers || { 'Content-Type': 'application/json', }; if (response.stream) { headers['Content-Type'] = 'text/event-stream'; headers['Cache-Control'] = 'no-cache'; headers['Connection'] = 'keep-alive'; res.writeHead(statusCode, headers); if (response.chunks) { for (const chunk of response.chunks) { res.write(`data: ${JSON.stringify(chunk)}\n\n`); } } res.write('data: [DONE]\n\n'); res.end(); } else { res.writeHead(statusCode, headers); res.end(JSON.stringify(response.body)); } }); } async start() { await new Promise<void>((resolve) => { this.server.listen(0, () => { this.port = (this.server.address() as AddressInfo).port; resolve(); }); }); } stop() { this.server.close(); } get baseUrl() { return `http://localhost:${this.port}/v1`; } setNextResponse(response: MockResponse) { this.responses.push(response); } }