screencast

This commit is contained in:
Chris Tate
2026-01-13 12:34:00 -06:00
parent e3a302056b
commit a60d986020
8 changed files with 870 additions and 4 deletions
+208
View File
@@ -11,10 +11,35 @@ import {
type Request,
type Route,
type Locator,
type CDPSession,
} from 'playwright-core';
import type { LaunchCommand } from './types.js';
import { type RefMap, type EnhancedSnapshot, getEnhancedSnapshot, parseRef } from './snapshot.js';
// Screencast frame data from CDP
export interface ScreencastFrame {
data: string; // base64 encoded image
metadata: {
offsetTop: number;
pageScaleFactor: number;
deviceWidth: number;
deviceHeight: number;
scrollOffsetX: number;
scrollOffsetY: number;
timestamp?: number;
};
sessionId: number;
}
// Screencast options
export interface ScreencastOptions {
format?: 'jpeg' | 'png';
quality?: number; // 0-100, only for jpeg
maxWidth?: number;
maxHeight?: number;
everyNthFrame?: number;
}
interface TrackedRequest {
url: string;
method: string;
@@ -54,6 +79,12 @@ export class BrowserManager {
private lastSnapshot: string = '';
private scopedHeaderRoutes: Map<string, (route: Route) => Promise<void>> = new Map();
// CDP session for screencast and input injection
private cdpSession: CDPSession | null = null;
private screencastActive: boolean = false;
private screencastSessionId: number = 0;
private frameCallback: ((frame: ScreencastFrame) => void) | null = null;
/**
* Check if browser is launched
*/
@@ -850,10 +881,186 @@ export class BrowserManager {
return tabs;
}
/**
* Get or create a CDP session for the current page
* Only works with Chromium-based browsers
*/
async getCDPSession(): Promise<CDPSession> {
if (this.cdpSession) {
return this.cdpSession;
}
const page = this.getPage();
const context = page.context();
// Create a new CDP session attached to the page
this.cdpSession = await context.newCDPSession(page);
return this.cdpSession;
}
/**
* Check if screencast is currently active
*/
isScreencasting(): boolean {
return this.screencastActive;
}
/**
* Start screencast - streams viewport frames via CDP
* @param callback Function called for each frame
* @param options Screencast options
*/
async startScreencast(
callback: (frame: ScreencastFrame) => void,
options?: ScreencastOptions
): Promise<void> {
if (this.screencastActive) {
throw new Error('Screencast already active');
}
const cdp = await this.getCDPSession();
this.frameCallback = callback;
this.screencastActive = true;
// Listen for screencast frames
cdp.on('Page.screencastFrame', async (params: any) => {
const frame: ScreencastFrame = {
data: params.data,
metadata: params.metadata,
sessionId: params.sessionId,
};
// Acknowledge the frame to receive the next one
await cdp.send('Page.screencastFrameAck', { sessionId: params.sessionId });
// Call the callback with the frame
if (this.frameCallback) {
this.frameCallback(frame);
}
});
// Start the screencast
await cdp.send('Page.startScreencast', {
format: options?.format ?? 'jpeg',
quality: options?.quality ?? 80,
maxWidth: options?.maxWidth ?? 1280,
maxHeight: options?.maxHeight ?? 720,
everyNthFrame: options?.everyNthFrame ?? 1,
});
}
/**
* Stop screencast
*/
async stopScreencast(): Promise<void> {
if (!this.screencastActive) {
return;
}
try {
const cdp = await this.getCDPSession();
await cdp.send('Page.stopScreencast');
} catch {
// Ignore errors when stopping
}
this.screencastActive = false;
this.frameCallback = null;
}
/**
* Inject a mouse event via CDP
*/
async injectMouseEvent(params: {
type: 'mousePressed' | 'mouseReleased' | 'mouseMoved' | 'mouseWheel';
x: number;
y: number;
button?: 'left' | 'right' | 'middle' | 'none';
clickCount?: number;
deltaX?: number;
deltaY?: number;
modifiers?: number; // 1=Alt, 2=Ctrl, 4=Meta, 8=Shift
}): Promise<void> {
const cdp = await this.getCDPSession();
const cdpButton =
params.button === 'left'
? 'left'
: params.button === 'right'
? 'right'
: params.button === 'middle'
? 'middle'
: 'none';
await cdp.send('Input.dispatchMouseEvent', {
type: params.type,
x: params.x,
y: params.y,
button: cdpButton,
clickCount: params.clickCount ?? 1,
deltaX: params.deltaX ?? 0,
deltaY: params.deltaY ?? 0,
modifiers: params.modifiers ?? 0,
});
}
/**
* Inject a keyboard event via CDP
*/
async injectKeyboardEvent(params: {
type: 'keyDown' | 'keyUp' | 'char';
key?: string;
code?: string;
text?: string;
modifiers?: number; // 1=Alt, 2=Ctrl, 4=Meta, 8=Shift
}): Promise<void> {
const cdp = await this.getCDPSession();
await cdp.send('Input.dispatchKeyEvent', {
type: params.type,
key: params.key,
code: params.code,
text: params.text,
modifiers: params.modifiers ?? 0,
});
}
/**
* Inject touch event via CDP (for mobile emulation)
*/
async injectTouchEvent(params: {
type: 'touchStart' | 'touchEnd' | 'touchMove' | 'touchCancel';
touchPoints: Array<{ x: number; y: number; id?: number }>;
modifiers?: number;
}): Promise<void> {
const cdp = await this.getCDPSession();
await cdp.send('Input.dispatchTouchEvent', {
type: params.type,
touchPoints: params.touchPoints.map((tp, i) => ({
x: tp.x,
y: tp.y,
id: tp.id ?? i,
})),
modifiers: params.modifiers ?? 0,
});
}
/**
* Close the browser and clean up
*/
async close(): Promise<void> {
// Stop screencast if active
if (this.screencastActive) {
await this.stopScreencast();
}
// Clean up CDP session
if (this.cdpSession) {
await this.cdpSession.detach().catch(() => {});
this.cdpSession = null;
}
// CDP: only disconnect, don't close external app's pages
if (this.cdpPort !== null) {
if (this.browser) {
@@ -880,5 +1087,6 @@ export class BrowserManager {
this.activePageIndex = 0;
this.refMap = {};
this.lastSnapshot = '';
this.frameCallback = null;
}
}