feat(network): implement listing network requests (#247)

Fixes: https://github.com/microsoft/playwright-mcp/issues/242

tests/testserver/index.ts

@@ -0,0 +1,145 @@
+/**
+ * Copyright 2017 Google Inc. All rights reserved.
+ * Modifications copyright (c) Microsoft Corporation.
+ *
+ * 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 fs from 'fs';
+import http from 'http';
+import https from 'https';
+import path from 'path';
+
+const fulfillSymbol = Symbol('fulfil callback');
+const rejectSymbol = Symbol('reject callback');
+
+export class TestServer {
+  private _server: http.Server;
+  readonly debugServer: any;
+  private _routes = new Map<string, (request: http.IncomingMessage, response: http.ServerResponse) => any>();
+  private _csp = new Map<string, string>();
+  private _extraHeaders = new Map<string, object>();
+  private _requestSubscribers = new Map<string, Promise<any>>();
+  readonly PORT: number;
+  readonly PREFIX: string;
+  readonly CROSS_PROCESS_PREFIX: string;
+
+  static async create(port: number): Promise<TestServer> {
+    const server = new TestServer(port);
+    await new Promise(x => server._server.once('listening', x));
+    return server;
+  }
+
+  static async createHTTPS(port: number): Promise<TestServer> {
+    const server = new TestServer(port, {
+      key: await fs.promises.readFile(path.join(__dirname, 'key.pem')),
+      cert: await fs.promises.readFile(path.join(__dirname, 'cert.pem')),
+      passphrase: 'aaaa',
+    });
+    await new Promise(x => server._server.once('listening', x));
+    return server;
+  }
+
+  constructor(port: number, sslOptions?: object) {
+    if (sslOptions)
+      this._server = https.createServer(sslOptions, this._onRequest.bind(this));
+    else
+      this._server = http.createServer(this._onRequest.bind(this));
+    this._server.listen(port);
+    this.debugServer = require('debug')('pw:testserver');
+
+    const cross_origin = '127.0.0.1';
+    const same_origin = 'localhost';
+    const protocol = sslOptions ? 'https' : 'http';
+    this.PORT = port;
+    this.PREFIX = `${protocol}://${same_origin}:${port}`;
+    this.CROSS_PROCESS_PREFIX = `${protocol}://${cross_origin}:${port}`;
+  }
+
+  setCSP(path: string, csp: string) {
+    this._csp.set(path, csp);
+  }
+
+  setExtraHeaders(path: string, object: Record<string, string>) {
+    this._extraHeaders.set(path, object);
+  }
+
+  async stop() {
+    this.reset();
+    await new Promise(x => this._server.close(x));
+  }
+
+  route(path: string, handler: (request: http.IncomingMessage, response: http.ServerResponse) => any) {
+    this._routes.set(path, handler);
+  }
+
+  redirect(from: string, to: string) {
+    this.route(from, (req, res) => {
+      const headers = this._extraHeaders.get(req.url!) || {};
+      res.writeHead(302, { ...headers, location: to });
+      res.end();
+    });
+  }
+
+  waitForRequest(path: string): Promise<http.IncomingMessage> {
+    let promise = this._requestSubscribers.get(path);
+    if (promise)
+      return promise;
+    let fulfill, reject;
+    promise = new Promise((f, r) => {
+      fulfill = f;
+      reject = r;
+    });
+    promise[fulfillSymbol] = fulfill;
+    promise[rejectSymbol] = reject;
+    this._requestSubscribers.set(path, promise);
+    return promise;
+  }
+
+  reset() {
+    this._routes.clear();
+    this._csp.clear();
+    this._extraHeaders.clear();
+    this._server.closeAllConnections();
+    const error = new Error('Static Server has been reset');
+    for (const subscriber of this._requestSubscribers.values())
+      subscriber[rejectSymbol].call(null, error);
+    this._requestSubscribers.clear();
+  }
+
+  _onRequest(request: http.IncomingMessage, response: http.ServerResponse) {
+    request.on('error', error => {
+      if ((error as any).code === 'ECONNRESET')
+        response.end();
+      else
+        throw error;
+    });
+    (request as any).postBody = new Promise(resolve => {
+      const chunks: Buffer[] = [];
+      request.on('data', chunk => {
+        chunks.push(chunk);
+      });
+      request.on('end', () => resolve(Buffer.concat(chunks)));
+    });
+    const path = request.url || '/';
+    this.debugServer(`request ${request.method} ${path}`);
+    // Notify request subscriber.
+    if (this._requestSubscribers.has(path)) {
+      this._requestSubscribers.get(path)![fulfillSymbol].call(null, request);
+      this._requestSubscribers.delete(path);
+    }
+    const handler = this._routes.get(path);
+    if (handler)
+      handler.call(null, request, response);
+  }
+}