| # Class: WebSocket |
| |
| > ⚠️ Warning: the WebSocket API is experimental. |
| |
| Extends: [`EventTarget`](https://developer.mozilla.org/en-US/docs/Web/API/EventTarget) |
| |
| The WebSocket object provides a way to manage a WebSocket connection to a server, allowing bidirectional communication. The API follows the [WebSocket spec](https://developer.mozilla.org/en-US/docs/Web/API/WebSocket) and [RFC 6455](https://datatracker.ietf.org/doc/html/rfc6455). |
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| ## `new WebSocket(url[, protocol])` |
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| Arguments: |
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| * **url** `URL | string` - The url's protocol *must* be `ws` or `wss`. |
| * **protocol** `string | string[] | WebSocketInit` (optional) - Subprotocol(s) to request the server use, or a [`Dispatcher`](./Dispatcher.md). |
| |
| ### Example: |
| |
| This example will not work in browsers or other platforms that don't allow passing an object. |
| |
| ```mjs |
| import { WebSocket, ProxyAgent } from 'undici' |
| |
| const proxyAgent = new ProxyAgent('my.proxy.server') |
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| const ws = new WebSocket('wss://echo.websocket.events', { |
| dispatcher: proxyAgent, |
| protocols: ['echo', 'chat'] |
| }) |
| ``` |
| |
| If you do not need a custom Dispatcher, it's recommended to use the following pattern: |
| |
| ```mjs |
| import { WebSocket } from 'undici' |
| |
| const ws = new WebSocket('wss://echo.websocket.events', ['echo', 'chat']) |
| ``` |
| |
| ## Read More |
| |
| - [MDN - WebSocket](https://developer.mozilla.org/en-US/docs/Web/API/WebSocket) |
| - [The WebSocket Specification](https://www.rfc-editor.org/rfc/rfc6455) |
| - [The WHATWG WebSocket Specification](https://websockets.spec.whatwg.org/) |