feat(debug): chromium debugging port (#2246)

This exposes Chromium remote debugging pipe under the port PLAYWRIGHT_CHROMIUM_DEBUG_PORT.

src/server/browserType.ts

@@ -77,18 +77,20 @@ export interface BrowserType {
 const mkdtempAsync = util.promisify(fs.mkdtemp);
 const DOWNLOADS_FOLDER = path.join(os.tmpdir(), 'playwright_downloads-');
 
+type WebSocketNotPipe = { webSocketRegex: RegExp, stream: 'stdout' | 'stderr' };
+
 export abstract class BrowserTypeBase implements BrowserType {
   private _name: string;
   private _executablePath: string | undefined;
-  private _webSocketRegexNotPipe: RegExp | null;
+  private _webSocketNotPipe: WebSocketNotPipe | null;
   readonly _browserPath: string;
 
-  constructor(packagePath: string, browser: browserPaths.BrowserDescriptor, webSocketRegexNotPipe: RegExp | null) {
+  constructor(packagePath: string, browser: browserPaths.BrowserDescriptor, webSocketOrPipe: WebSocketNotPipe | null) {
     this._name = browser.name;
     const browsersPath = browserPaths.browsersPath(packagePath);
     this._browserPath = browserPaths.browserDirectory(browsersPath, browser);
     this._executablePath = browserPaths.executablePath(this._browserPath, browser);
-    this._webSocketRegexNotPipe = webSocketRegexNotPipe;
+    this._webSocketNotPipe = webSocketOrPipe;
   }
 
   executablePath(): string {
@@ -203,7 +205,7 @@ export abstract class BrowserTypeBase implements BrowserType {
       handleSIGTERM,
       handleSIGHUP,
       progress,
-      pipe: !this._webSocketRegexNotPipe,
+      pipe: !this._webSocketNotPipe,
       tempDirectories,
       attemptToGracefullyClose: async () => {
         if ((options as any).__testHookGracefullyClose)
@@ -221,8 +223,8 @@ export abstract class BrowserTypeBase implements BrowserType {
     browserServer = new BrowserServer(launchedProcess, gracefullyClose, kill);
     progress.cleanupWhenCanceled(() => browserServer && browserServer._closeOrKill(progress.deadline));
 
-    if (this._webSocketRegexNotPipe) {
+    if (this._webSocketNotPipe) {
-      const match = await waitForLine(progress, launchedProcess, launchedProcess.stdout, this._webSocketRegexNotPipe);
+      const match = await waitForLine(progress, launchedProcess, this._webSocketNotPipe.stream === 'stdout' ? launchedProcess.stdout : launchedProcess.stderr, this._webSocketNotPipe.webSocketRegex);
       const innerEndpoint = match[1];
       transport = await WebSocketTransport.connect(progress, innerEndpoint);
     } else {

src/server/chromium.ts

@@ -16,7 +16,7 @@
  */
 
 import * as path from 'path';
-import { helper, assert } from '../helper';
+import { helper, assert, getFromENV, logPolitely } from '../helper';
 import { CRBrowser } from '../chromium/crBrowser';
 import * as ws from 'ws';
 import { Env } from './processLauncher';
@@ -32,9 +32,19 @@ import { BrowserOptions } from '../browser';
 
 export class Chromium extends BrowserTypeBase {
   private _devtools: CRDevTools | undefined;
+  private _debugPort: number | undefined;
 
   constructor(packagePath: string, browser: BrowserDescriptor) {
-    super(packagePath, browser, null /* use pipe not websocket */);
+    const debugPortStr = getFromENV('PLAYWRIGHT_CHROMIUM_DEBUG_PORT');
+    const debugPort: number | undefined = debugPortStr ? +debugPortStr : undefined;
+    if (debugPort !== undefined) {
+      if (Number.isNaN(debugPort))
+        throw new Error(`PLAYWRIGHT_CHROMIUM_DEBUG_PORT must be a number, but is set to "${debugPortStr}"`);
+      logPolitely(`NOTE: Chromium will be launched in debug mode on port ${debugPort}`);
+    }
+
+    super(packagePath, browser, debugPort ? { webSocketRegex: /^DevTools listening on (ws:\/\/.*)$/, stream: 'stderr' } : null);
+    this._debugPort = debugPort;
     if (debugSupport.isDebugMode())
       this._devtools = this._createDevTools();
   }
@@ -79,7 +89,10 @@ export class Chromium extends BrowserTypeBase {
       throw new Error('Arguments can not specify page to be opened');
     const chromeArguments = [...DEFAULT_ARGS];
     chromeArguments.push(`--user-data-dir=${userDataDir}`);
-    chromeArguments.push('--remote-debugging-pipe');
+    if (this._debugPort !== undefined)
+      chromeArguments.push('--remote-debugging-port=' + this._debugPort);
+    else
+      chromeArguments.push('--remote-debugging-pipe');
     if (devtools)
       chromeArguments.push('--auto-open-devtools-for-tabs');
     if (headless) {

src/server/firefox.ts

@@ -32,8 +32,8 @@ import { BrowserDescriptor } from '../install/browserPaths';
 
 export class Firefox extends BrowserTypeBase {
   constructor(packagePath: string, browser: BrowserDescriptor) {
-    const websocketRegex = /^Juggler listening on (ws:\/\/.*)$/;
+    const webSocketRegex = /^Juggler listening on (ws:\/\/.*)$/;
-    super(packagePath, browser, websocketRegex /* use websocket not pipe */);
+    super(packagePath, browser, { webSocketRegex, stream: 'stdout' });
   }
 
   _connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<FFBrowser> {