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createWebsocketHandoff

Functionin websocket@fastly/js-compute 4.0.0since 3.34.0View source
createWebsocketHandoff(request: Request, backend: string): Response

Create a Response that instructs Fastly to pass the original request through as a WebSocket connection to the specified backend.

Note: Can only be used when processing requests, not during build-time initialization.

Parameters

request: Request

The request to pass through as a WebSocket connection

backend: string

The name of the backend to send the request to (1–254 characters)

Returns

Response

Throws

  • Throws an Error if request is not a Request instance, or if backend is empty or longer than 254 characters
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import { createWebsocketHandoff } from "fastly:websocket";


async function handleRequest(event) {
    const url = new URL(event.request.url);
    if (url.pathname === '/stream') {
        return createWebsocketHandoff(event.request, 'websocket-backend');
    }
    return new Response('Not found', { status: 404 });
}


addEventListener("fetch", (event) => event.respondWith(handleRequest(event)));
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