Implementation:DevExpress Testcafe ChromeProvider

Knowledge Sources	DevExpress_Testcafe TestCafe Docs
Domains	Browser Automation, Chrome DevTools Protocol
Last Updated	2026-02-12 12:00 GMT

Overview

The Chrome browser provider manages the full lifecycle of Chrome browser instances for TestCafe test execution, including launching, resizing, screenshotting, video capture, native automation, and closing.

Description

The Chrome provider is an object literal exported from src/browser/provider/built-in/dedicated/chrome/index.js that extends the dedicatedProviderBase mixin. It implements browser lifecycle methods that TestCafe's browser connection infrastructure calls to open, control, and close Chrome browser instances. The provider supports both standard and Docker-containerized Chrome, headless mode, device emulation, CDP-based native automation, and multi-window management. It delegates low-level CDP communication to a BrowserClient instance and tracks per-browser state in the openedBrowsers map inherited from the base.

Usage

This provider is used internally by TestCafe whenever a user specifies chrome (or a Chrome variant such as chrome:headless) as the target browser. It is not instantiated directly by end users; instead, TestCafe's browser provider pool discovers it as a built-in dedicated provider and invokes its methods through the BrowserProviderPluginHost wrapper.

Code Reference

Source Location

Repository: DevExpress_Testcafe
File: src/browser/provider/built-in/dedicated/chrome/index.js
Lines: 1-239

Signature

export default {
    ...dedicatedProviderBase,

    getConfig (name),
    async getCurrentCDPSession (browserId),
    _getBrowserProtocolClient (runtimeInfo),
    async _createRunTimeInfo (hostName, config, disableMultipleWindows),
    _setUserAgentMetaInfoForEmulatingDevice (browserId, config),
    async _setupNativeAutomation ({ browserClient, runtimeInfo, nativeAutomationOptions }),
    async _startChrome (startOptions, pageUrl),
    async openBrowser (browserId, pageUrl, config, additionalOptions),
    async closeBrowser (browserId, closingInfo = {}),
    async resizeWindow (browserId, width, height, currentWidth, currentHeight),
    async maximizeWindowNativeAutomation (browserId),
    async resizeBounds (browserId, width, height, currentWidth, currentHeight),
    async startCapturingVideo (browserId),
    async stopCapturingVideo (browserId),
    async getVideoFrameData (browserId),
    async hasCustomActionForBrowser (browserId),
    async _ensureWindowIsExpanded (browserId, { height, width, availableHeight, availableWidth, outerWidth, outerHeight }),
    async openFileProtocol (browserId, url),
    async dispatchNativeAutomationEvent (browserId, type, options),
    async dispatchNativeAutomationEventSequence (browserId, eventSequence),
    supportNativeAutomation (),
    getNativeAutomation (browserId),
    async getNewWindowIdInNativeAutomation (browserId),
};

Import

import chromeProvider from '../browser/provider/built-in/dedicated/chrome/index.js';

I/O Contract

Key Method: openBrowser

Input	Type	Description
browserId	string	Unique identifier assigned by TestCafe for this browser connection
pageUrl	string	The initial URL (typically the TestCafe proxy URL) the browser navigates to
config	object	Parsed Chrome configuration (headless, emulation, deviceName, mobile, etc.)
additionalOptions	object	Extra flags including nativeAutomation (boolean) and disableMultipleWindows (boolean)

Output	Type	Description
(side effect)	void	Populates this.openedBrowsers[browserId] with runtimeInfo, browserClient, viewportSize, and windowDescriptors

Key Method: closeBrowser

Input	Type	Description
browserId	string	Unique identifier of the browser to close
closingInfo	object	Optional object; when isRestarting is true, temp profile directory is preserved

Output	Type	Description
(side effect)	void	Disposes native automation, closes browser process, removes temp profile, and deletes browserId from openedBrowsers

Key Method: hasCustomActionForBrowser

Output Key	Type	Description
hasCloseBrowser	boolean	Always true
hasResizeWindow	boolean	True when CDP client exists and config has emulation or headless
hasMaximizeWindow	boolean	True when CDP client exists and config is headless
hasTakeScreenshot	boolean	True when CDP client exists
hasChromelessScreenshots	boolean	True when CDP client exists
hasGetVideoFrameData	boolean	True when CDP client exists
hasCanResizeWindowToDimensions	boolean	Always false

Usage Examples

// TestCafe uses the Chrome provider internally. Users interact with it
// through the TestCafe runner API:

import createTestCafe from 'testcafe';

const testcafe = await createTestCafe('localhost', 1337, 1338);
const runner   = testcafe.createRunner();

await runner
    .src('tests/example.js')
    .browsers('chrome:headless')    // triggers ChromeProvider.openBrowser()
    .run();

await testcafe.close();             // triggers ChromeProvider.closeBrowser()

// Internal lifecycle sequence executed by TestCafe:
// 1. provider.openBrowser(browserId, proxyUrl, config, additionalOptions)
//    - Creates ChromeRunTimeInfo
//    - Launches Chrome (local or Docker)
//    - Waits for connection ready
//    - Initializes BrowserClient and native automation
// 2. provider.resizeWindow(browserId, w, h, curW, curH)
// 3. provider.takeScreenshot(browserId, path, vpW, vpH, fullPage)  [from base]
// 4. provider.closeBrowser(browserId, closingInfo)

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