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browsertype/methods

14 notes, read out of this brain and free to use. Each one was extracted from a source and is re-checked against its exam.

BrowserType.connect method

async method that attaches Playwright to an existing browser instance created via BrowserType.launchServer. Returns a Browser. Available since v1.8. The major and minor version of the Playwright instance that connects needs to match the version of Playwright that launches the browser (1.2.3 → is compatible with 1.2.x).

BrowserType.connect parameters and options

BrowserType.connect accepts the following: Parameter: - endpoint (string, since v1.10): A Playwright browser websocket endpoint to connect to. You obtain this endpoint via BrowserServer.wsEndpoint. Options: - headers (Object<string, string>, since v1.11): Additional HTTP headers to be sent with web socket connect request. Optional. - slowMo (float, since v1.10): Slows down Playwright operations by the specified amount of milliseconds. Defaults to 0. - timeout (float, since v1.10): Maximum time in milliseconds to wait for the connection to be established. Defaults to 0 (no timeout). - exposeNetwork (string, since v1.37): Exposes network available on the connecting client to the browser being connected to. Consists of a list of rules separated by comma. Available rules: hostname pattern (e.g., example.com, *.org:99, x.*.y.com, *foo.org), IP literal (e.g., 127.0.0.1, 0.0.0.0:99, [::1], [0:0::1]:99), or <loopback> that matches local loopback interfaces.

BrowserType.connectOverCDP method

async method that attaches Playwright to an existing browser instance using the Chrome DevTools Protocol. Returns a Browser. Available since v1.9. The default browser context is accessible via Browser.contexts. Connecting over the Chrome DevTools Protocol is only supported for Chromium-based browsers. This connection is significantly lower fidelity than the Playwright protocol connection via BrowserType.connect.

BrowserType.connectOverCDP parameters and options

BrowserType.connectOverCDP accepts the following: Parameter: - endpointURL (string, since v1.11): A CDP websocket endpoint or http url to connect to. For example http://localhost:9222/ or ws://127.0.0.1:9222/devtools/browser/387adf4c-243f-4051-a181-46798f4a46f4. Options: - endpointURL (string, since v1.14, JavaScript only, deprecated): Use the first argument instead. - headers (Object<string, string>, since v1.11): Additional HTTP headers to be sent with connect request. Optional. - isLocal (boolean, since v1.58): Tells Playwright that it runs on the same host as the CDP server. Enables certain optimizations that rely upon the file system being the same between Playwright and the Browser. - slowMo (float, since v1.11): Slows down Playwright operations by the specified amount of milliseconds. Defaults to 0. - timeout (float, since v1.11): Maximum time in milliseconds to wait for the connection to be established. Defaults to 30000 (30 seconds). Pass 0 to disable timeout. - noDefaults (boolean, since v1.60): When true, Playwright will not apply its default overrides to the existing default browser context. Defaults to false. - artifactsDir (path, since v1.61): If specified, browser artifacts (such as traces and downloads) are saved into this directory.

BrowserType.connectOverCDP example

const browser = await playwright.chromium.connectOverCDP('http://localhost:9222'); const defaultContext = browser.contexts()[0]; const page = defaultContext.pages()[0];

BrowserType.executablePath method

Returns a string representing a path where Playwright expects to find a bundled browser executable. Available since v1.8.

BrowserType.launch method

async method that launches and returns a browser instance. Available since v1.8. The method accepts various options including ignoreDefaultArgs to filter out specific command-line arguments from defaults.

BrowserType.launch example

const browser = await chromium.launch({ // Or 'firefox' or 'webkit'. ignoreDefaultArgs: ['--mute-audio'] });

BrowserType.launchPersistentContext method

async method that launches a browser using persistent storage and returns the only browser context instance. Closing this context will automatically close the browser. Available since v1.8. Returns a BrowserContext.

BrowserType.launchPersistentContext userDataDir parameter

BrowserType.launchPersistentContext requires a userDataDir parameter (path, since v1.8) that specifies the path to a User Data Directory, which stores browser session data like cookies and local storage. Pass an empty string to create a temporary directory. Browsers do not allow launching multiple instances with the same User Data Directory. For Chromium, this is the parent directory of the "Profile Path" seen at chrome://version.

BrowserType.launchServer method

async method available in JavaScript (since v1.8) that launches a browser server that a client can connect to later via BrowserType.connect. Returns a BrowserServer. The major/minor client/server version must match (1.2.3 → is compatible with 1.2.x).

BrowserType.launchServer options: host, port, wsPath

BrowserType.launchServer accepts the following options: - host (string, since v1.45): Host to use for the web socket. Defaults to localhost, accepting connections only from the loopback interface. Pass an explicit address (e.g., 0.0.0.0) to accept connections from the network. - port (int, since v1.8): Port to use for the web socket. Defaults to 0 that picks any available port. - wsPath (string, since v1.15): Path at which to serve the Browser Server. For security, this defaults to an unguessable string.

BrowserType.launchServer example

const { chromium } = require('playwright'); // Or 'webkit' or 'firefox'. (async () => { const browserServer = await chromium.launchServer(); const wsEndpoint = browserServer.wsEndpoint(); // Use web socket endpoint later to establish a connection. const browser = await chromium.connect(wsEndpoint); // Close browser instance. await browserServer.close(); })();

BrowserType.name method

Returns a string representing the browser name. For example: 'chromium', 'webkit' or 'firefox'. Available since v1.8.

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